Stanford SSI Wiki - User contributions [en]

HPR Background Information

2017-03-08T23:07:21Z

Iangomez: Added pie chart

High power rocketry (HPR) is an essential and hands-on part of learning the fundamentals of rocketry.

NASA's online [https://spaceflightsystems.grc.nasa.gov/education/rocket/shortr.html Beginner's Guide To Rockets] will get you started on many of the basic principles governing rocketry. If you manage to make your way through all of these, you will understand the vernacular often used in rocketry. To learn more about rocketry, the theory behind it, and other useful things related to rockets, see [[So You Want To...]].

In addition that resource, here are some concepts compiled so you can quickly grasp what you need to know. If you are attempting an L1 certification, check out [[L1 Certification]].

== Jargon ==

=== Impulse and its Specificity ===

Impulse (or total impulse) is defined as equal to force multiplied by time - it is a measure of how powerful motors are, and can easily give you your change in velocity, Impulse / Mass, assuming no drag or gravity losses. (There will always be drag and gravity losses.) Total impulse can be thought of as the area under the thrust curve.

[[File:L1_Guide_Thrust_Curve.png|400px|thumb|frame|center|Thrust curves of motors with the same total impulse]]

In the above graph, each of those three motors have the same total impulse (area under the curve), but with very different thrust profiles. The letter designation for each motor (e.g. in E15, H125, or M1250) are a measure of total impulse and each successive letter represents double the total impulse.

It turns out that impulse alone is not a gooad measure for rocket fuel performance; it is technically possible to use wood and air as rocket fuels, and to get an insanely large impulse by making the engine really big. That will never get you to space. Instead, rockets really care about a number called the specific impulse, defined as impulse divided by the mass of the propellant and the gravitational constant. This gives a far better picture of what constitutes a good rocket fuel, although there are definitely other considerations.

=== Motor Systems (DMS and RMS) ===
[[File:DMSMotor.jpg|thumb|200px|right|A DMS with its packaging]]

DMS stands for Disposable Motor System. These motors are one time use only, and are very easy to work with.

RMS stands for Reloadable Motor System. These types of motors are harder to work with, since they require the maintenance of a motor casing and proficiency in loading, cleaning, and reloading the casing. After purchasing the relatively expensive casing, one must learn how to assemble it with motor reloads. If not assembled properly, your rocket will most likely not make it through the flight. However, once you become good at assembling and using RMS, it is cheaper to merely have to purchase propellant each time you launch instead of an entirely new DMS motor.

=== Motor Retention (Positive or Otherwise) and Adaptors ===

There is one direction we care about when discussing motor retention, the y direction (axially). Simply put, the job of a motor retainer is to keep your motor from falling out of your rocket or allowing it to shoot through the nosecone upon ignition, resulting in a cato. Depending on the company, motor retainers have a couple different ways they work. For the slimline retainers used in the SSI Firestorm kit, the motor retainers use retaining rings. These rings are removable and are located on the lip of the the retainer. The purpose of the rings are to keep the motor from sliding out of the bottom while a lip on the body of the retainer prevents the motor from launching through the rocket's nosecone. For any 38mm motor being used in the 58mm Firestorm airframe, a motor adaptor is going to be used which has identical retaining rings, except smaller in diameter, to the motor retainer.

You can purchase/make motor adaptors which allow you to have a motor of a diameter that is smaller than the diameter of your rocket. For example: If one wanted to launch an L1 with a 54mm H motor but his or her rocket had an ID of 98mm, that person would purchase/make a motor adapter to keep the motor stable and restrained. Motor adapters consist of a tube that has the same ID as the motor's OD and uses centering rings to keep the motor centered between the airframe walls. If you are planning on using various diameter motors for the same airframe it might be a wise choice to invest in a motor retention system that allows the user to buy various components designed to work with different sized motors.

'''Some Quick Terminology'''
Positive = not falling out the bottom.

== Static Stability ==

[[File:L1_Guide_Stability.png|thumb|200px|right|CG and CP for stable flight]]

=== Brief History ===
In 1958, G. Harry Stine published a simplified discussion of rocket stabilization geared towards model rockets using fixed fins on the rear of a rocket. The fins, if properly designed, provide a means of inducing a return to the desired flight path when a disturbance acts to rotate the rocket around its center of gravity (CG or c.g.). The air forces acting on a rocket can be thought of as all acting at a center of pressure (CP). He suggested a method of approximating the CP by constructing a cardboard cutout of the model and balancing the plan-form cutout.

The next advance in design came in 1966, when James Barrowman, then of NASA’s Sounding
Rocket Division, presented a closed form algebraic solution to equations based on potential flow theory. The approximations used to achieve the closed form solution rely on the assumptions that the rocket (a) is traveling at a speed below that at which shock waves are formed (somewhat below the speed of sound), and (b) has a small angle between its flight path and the relative wind (i.e. a small angle of attack, or AOA). The Barrowman Equations continue to be widely used, both in graphical form and as the basis for hobby rocket design analysis software. From the "Launching Safely in the 21st Century: Final Report of the Special Committee on Range Operation and Procedure to the National Association of Rocketry", 2005.

=== Center of Gravity ===

An objects center of gravity is its (rigorously and mathematically defined) middle point. The force of gravity can be simulated to act here, and the object will tend to rotate about this point, making it crucial to finding rocket stability.

The relation of CG to your L1 rocket is its relation to the center of pressure (CP). For stable flight your CG needs to be towards the nosecone of your CP. If you determine that your CG is too close to your CP and need to move it forward because you can't change the position of your CP, a common method is to add some mass weight to your nosecone.

=== Center of Pressure ===
The center of pressure is the location at which we can model the aerodynamic effects as acting. In other words, the drag on the rocket acts at this point. If the center of pressure is below the center of gravity, then the downwards force of drag will keep the rocket upright, while a center of pressure above the center of gravity will flip the rocket. A CP and CG at the same point will create a neutrally stable rocket, meaning that any incidental forces could theoretically spin it. This makes the distance between the CP and CG critically important for determining whether flight will be safe and successful.

The main tool we have to change the center of pressure is the size of the rocket's fins - larger fins will bring the center of pressure lower down on the rocket, increasing its stability.

To calculate center of pressure, you can use the Barrowman equations ([http://www.scalerocketry.com/equations/barrowman.htm link to a slighty confusing example]) or the [https://www.apogeerockets.com/education/downloads/Newsletter18.pdf cardboard cutout method].

Another way to determine the CP of your rocket is to use a program like OpenRocket or RockSim. Both of these programs take all the information you input about your rocket and input into the Barrowman equations for you.

=== Calibers ===

A caliber is a unit of measurement defined as the diameter of the airframe. Calibers are used to measure the distance between the CP and CG - it doesn't make sense to solely measure based on distance, as a 3" difference on a 2" OD, 24" long rocket is very different from a 2" difference on a 10' long, 6" OD one.

Calibers measure the length between CP and CG allowing for a much more fair comparison between different rocket sizes. It would be correct to say, the CG is 2 calibers away from the CP.

As a rule of thumb, having your CP 1.5-2 calibers in front of your CG is considered good, while numbers outside of that range tend to be either under-or-over-stable.

== Failure ==

[[File:MASA_flight_failure.PNG|400px|thumb|frame|right|Failure mode pie chart]]

There is a fantastic NAR case study, "Launching Safely in the 21st Century", written by the Special Committee on Range Operation and Procedure which goes into rigorous statistical analysis of rocket failures. The following categories are common failure modes recorded from the fight log database of the Minnesota Amateur Spacemodeler Association (MASA, NAR 576):

'''Unstable.''' The rocket flies with at least part of the boost phase in a nose-down attitude. For
the purposes of this study, based on the goal to characterize unsafe events, comments such
as "kind of unstable" were not counted, nor were "horizontal", "cruise missile", or "coning"
flights (unless they resulted in a crash; see below).

'''Lawn dart.''' The rocket descends in ballistic flight with the nose cone still on. This category
includes "No ejection" and a few "power prangs". Some rockets are designed to do this and
these flights were not counted. Boosters on two stage rockets also did this.

'''Separation.''' The rocket descends in multiple parts with at least one part not slowed by a
recovery device. For the purposes of this study, the few flights with a comment of "stripped
chute" were included here. The unplanned ejection of motor casings should also have been
collected here, but MASA LCOs almost never recorded them as outcomes.

'''Motor CATO.''' The motor failures catastrophically at ignition or during boost. The nature of
the CATO (spit nozzle, forward closure failure, blow by, etc.) was sometimes recorded, but
not consistently.

'''Core sample.''' The rocket descends in ballistic flight, but with the nose cone off the rocket
and acting as a (not very effective) streamer. These events typically have lower impact
speeds, and higher surface areas at impact, than do lawn darts.

'''Motor unrestrained.''' The motor exits the rocket at ignition or during boost (thankfully, this
was rare).

'''Shred.''' The rocket comes apart during ascent, other than by design.

'''No chute.''' The rocket descends without a recovery device deployed, but is not ballistic. This
category does not include chutes that were described as merely tangled, although it is likely
that some LCOs write "no chute" in those circumstances. The rationale here is that if the
LCO described the result as "No chute", it was potentially unsafe.

These would be called "recordable incidents" in the jargon of safety professionals. When more than one failure occurred during a flight (e.g., unstable flight leading to lawn dart), the most severe event was recorded.

== Motor Specs ==

Solid rocket motors have a fairly standardized labeling system. On the casing (or reload) itself there is a three-part code which denotes what the total impulse range is, the average thrust, and the delay grain length. All these numbers are in standard metric units.

The letter designation represents the total impulse. Each letter category represents double the total impulse of the previous letter category.

[[File:L1_Guide_Motor_Classification.png|300px|thumb|frame|center|Letter designations increase total impulse exponentially]]

Motor classification table:

[[File:MotorClassification.png|300px|thumb|center|Motor Classification]]

===Motor Designation Breakdown===
To better understand how to read a motor label lets take an example:

'''Aerotech H550ST-14A'''

Here is the spec sheet for this motor[http://www.aerotech-rocketry.com/uploads/4e952284-bb4b-4943-8904-9a0719e8ee3a_AT%20H550ST%20SU%20jun%2019.pdf]. This is the motor that SSI uses for its L1 certification launches.

*'''H''': the letter designating the impulse range. For an H this is from 160 Ns - 320 Ns.
*'''550''': denotes that the motor's average thrust is 550 N.
*'''ST''': denotes what type of propellant is in the casing. In this case, ST stands for "Super Thunder". Aerotech has various names for their different types of propellants, however, often these names are only denoting the color of the flame rather than the chemical compounds that it is made of.
*'''14''': denotes that the motor will fire its ejection charge 14 s after burnout unless it is adjusted, as indicated by the A. Motor delay times can be adjusted with a motor delay tool (otherwise known as a proprietary screwdriver, here is a link to buy one[http://www.buyrocketmotors.com/aerotech-universal-delay-drilling-tool-for-dms-motors/]).

== Recovery ==

[[File:L1_Guide_Delay_Charge.png|thumb|165px|right|Motor delay charge]]
Recovery is the second stage of a simple non-complex rocket, aka basic L1. Although it would seem like the largest percentage of failure would happen during ascent, 75% of failed rockets are a result of a faulty recovery system. Common points of failure for an L1 are: the parachute did not deploy out of the airframe, the parachute deployed too soon before or too far after apogee, line tangling, and too quick of a descent. All of these aspects are things that you should consider when compiling your recovery system.

For L1 all a rocketeer needs is single stage deployment. Simply put, only a main parachute is required to bring the rocket safely back to the ground. Because it is single stage, the parachute should be ejected as close to apogee as possible to prevent unnecessary damage to the rocket. Apogee is the highest point of a rocket trajectory, where the vertical velocity is momentarily zero and the rocket transitions from ascent to descent. This is the point at which the rocket is moving slowest and thus is the most ideal for deployment of a parachute.

For typical L1 rockets, after the motor burns through its main propellant, it burns through a delay grain. This is a slow-burning section at the end of the motor which acts as a timer. Once it has burned through the delay grain, the flame front ignites an ejection charge loaded in the charge well at the front of the motor. This ejection charge, typically black powder, pressurizes the body tube of the rocket and forces the nose cone out, along with the parachute. To test whether your nose cone has the proper fit (tight enough to stay on during flight but loose enough to eject for recovery), hold the back end of your completed, and unloaded, rocket to your mouth and blow hard with a good seal. The nose cone and parachute should both pop out. If you are incapable of doing this, another test can be done by vigorously shaking the rocket by holding the nosecone. The nosecone should separate from the rocket by doing this.

== Simulations ==

[[File:exampleOpenRocket.jpg|thumb|right|300px|Example of the OpenRocket interface]]

It is always important to know what your rocket will do (assuming that things go according to plan), and we use a program called OpenRocket to find the flight profile of our rockets. The program is free, and can be found here[http://openrocket.sourceforge.net/]

OpenRocket is quite easy to learn, and is quite accurate for sub-Mach rockets (those that fly faster should use RasAero to model drag forces.) OpenRocket includes ascent, including a massive database of thrust curves, as well as a simulated descent using the parachutes included in the rocket. If used properly, it can output data from height of apogee to time of flight to drift distance, all of which are incredibly useful while designing your rocket. (Hint: the center of pressure calculation is extremely important.)

One other program of note is called FinSim, which can model possible vibrations within fins. If unchecked, these vibrations can grow and shear the fins off, likely dooming the rocket. The program is required for transonic and supersonic flights, and can be found here[http://www.aerorocket.com/finsim.html]

{{reflist}}

[[Category: Rockets]]

File:MASA flight failure.PNG

2017-03-08T23:03:46Z

Iangomez:

HPR Background Information

2017-03-08T23:02:34Z

Iangomez: Added failure modes and stability info

High power rocketry (HPR) is an essential and hands-on part of learning the fundamentals of rocketry.

NASA's online [https://spaceflightsystems.grc.nasa.gov/education/rocket/shortr.html Beginner's Guide To Rockets] will get you started on many of the basic principles governing rocketry. If you manage to make your way through all of these, you will understand the vernacular often used in rocketry. To learn more about rocketry, the theory behind it, and other useful things related to rockets, see [[So You Want To...]].

In addition that resource, here are some concepts compiled so you can quickly grasp what you need to know. If you are attempting an L1 certification, check out [[L1 Certification]].

== Jargon ==

=== Impulse and its Specificity ===

Impulse (or total impulse) is defined as equal to force multiplied by time - it is a measure of how powerful motors are, and can easily give you your change in velocity, Impulse / Mass, assuming no drag or gravity losses. (There will always be drag and gravity losses.) Total impulse can be thought of as the area under the thrust curve.

[[File:L1_Guide_Thrust_Curve.png|400px|thumb|frame|center|Thrust curves of motors with the same total impulse]]

In the above graph, each of those three motors have the same total impulse (area under the curve), but with very different thrust profiles. The letter designation for each motor (e.g. in E15, H125, or M1250) are a measure of total impulse and each successive letter represents double the total impulse.

It turns out that impulse alone is not a gooad measure for rocket fuel performance; it is technically possible to use wood and air as rocket fuels, and to get an insanely large impulse by making the engine really big. That will never get you to space. Instead, rockets really care about a number called the specific impulse, defined as impulse divided by the mass of the propellant and the gravitational constant. This gives a far better picture of what constitutes a good rocket fuel, although there are definitely other considerations.

=== Motor Systems (DMS and RMS) ===
[[File:DMSMotor.jpg|thumb|200px|right|A DMS with its packaging]]

DMS stands for Disposable Motor System. These motors are one time use only, and are very easy to work with.

RMS stands for Reloadable Motor System. These types of motors are harder to work with, since they require the maintenance of a motor casing and proficiency in loading, cleaning, and reloading the casing. After purchasing the relatively expensive casing, one must learn how to assemble it with motor reloads. If not assembled properly, your rocket will most likely not make it through the flight. However, once you become good at assembling and using RMS, it is cheaper to merely have to purchase propellant each time you launch instead of an entirely new DMS motor.

=== Motor Retention (Positive or Otherwise) and Adaptors ===

There is one direction we care about when discussing motor retention, the y direction (axially). Simply put, the job of a motor retainer is to keep your motor from falling out of your rocket or allowing it to shoot through the nosecone upon ignition, resulting in a cato. Depending on the company, motor retainers have a couple different ways they work. For the slimline retainers used in the SSI Firestorm kit, the motor retainers use retaining rings. These rings are removable and are located on the lip of the the retainer. The purpose of the rings are to keep the motor from sliding out of the bottom while a lip on the body of the retainer prevents the motor from launching through the rocket's nosecone. For any 38mm motor being used in the 58mm Firestorm airframe, a motor adaptor is going to be used which has identical retaining rings, except smaller in diameter, to the motor retainer.

You can purchase/make motor adaptors which allow you to have a motor of a diameter that is smaller than the diameter of your rocket. For example: If one wanted to launch an L1 with a 54mm H motor but his or her rocket had an ID of 98mm, that person would purchase/make a motor adapter to keep the motor stable and restrained. Motor adapters consist of a tube that has the same ID as the motor's OD and uses centering rings to keep the motor centered between the airframe walls. If you are planning on using various diameter motors for the same airframe it might be a wise choice to invest in a motor retention system that allows the user to buy various components designed to work with different sized motors.

'''Some Quick Terminology'''
Positive = not falling out the bottom.

== Static Stability ==

[[File:L1_Guide_Stability.png|thumb|200px|right|CG and CP for stable flight]]

=== Brief History ===
In 1958, G. Harry Stine published a simplified discussion of rocket stabilization geared towards model rockets using fixed fins on the rear of a rocket. The fins, if properly designed, provide a means of inducing a return to the desired flight path when a disturbance acts to rotate the rocket around its center of gravity (CG or c.g.). The air forces acting on a rocket can be thought of as all acting at a center of pressure (CP). He suggested a method of approximating the CP by constructing a cardboard cutout of the model and balancing the plan-form cutout.

The next advance in design came in 1966, when James Barrowman, then of NASA’s Sounding
Rocket Division, presented a closed form algebraic solution to equations based on potential flow theory. The approximations used to achieve the closed form solution rely on the assumptions that the rocket (a) is traveling at a speed below that at which shock waves are formed (somewhat below the speed of sound), and (b) has a small angle between its flight path and the relative wind (i.e. a small angle of attack, or AOA). The Barrowman Equations continue to be widely used, both in graphical form and as the basis for hobby rocket design analysis software. From the "Launching Safely in the 21st Century: Final Report of the Special Committee on Range Operation and Procedure to the National Association of Rocketry", 2005.

=== Center of Gravity ===

An objects center of gravity is its (rigorously and mathematically defined) middle point. The force of gravity can be simulated to act here, and the object will tend to rotate about this point, making it crucial to finding rocket stability.

The relation of CG to your L1 rocket is its relation to the center of pressure (CP). For stable flight your CG needs to be towards the nosecone of your CP. If you determine that your CG is too close to your CP and need to move it forward because you can't change the position of your CP, a common method is to add some mass weight to your nosecone.

=== Center of Pressure ===
The center of pressure is the location at which we can model the aerodynamic effects as acting. In other words, the drag on the rocket acts at this point. If the center of pressure is below the center of gravity, then the downwards force of drag will keep the rocket upright, while a center of pressure above the center of gravity will flip the rocket. A CP and CG at the same point will create a neutrally stable rocket, meaning that any incidental forces could theoretically spin it. This makes the distance between the CP and CG critically important for determining whether flight will be safe and successful.

The main tool we have to change the center of pressure is the size of the rocket's fins - larger fins will bring the center of pressure lower down on the rocket, increasing its stability.

To calculate center of pressure, you can use the Barrowman equations ([http://www.scalerocketry.com/equations/barrowman.htm link to a slighty confusing example]) or the [https://www.apogeerockets.com/education/downloads/Newsletter18.pdf cardboard cutout method].

Another way to determine the CP of your rocket is to use a program like OpenRocket or RockSim. Both of these programs take all the information you input about your rocket and input into the Barrowman equations for you.

=== Calibers ===

A caliber is a unit of measurement defined as the diameter of the airframe. Calibers are used to measure the distance between the CP and CG - it doesn't make sense to solely measure based on distance, as a 3" difference on a 2" OD, 24" long rocket is very different from a 2" difference on a 10' long, 6" OD one.

Calibers measure the length between CP and CG allowing for a much more fair comparison between different rocket sizes. It would be correct to say, the CG is 2 calibers away from the CP.

As a rule of thumb, having your CP 1.5-2 calibers in front of your CG is considered good, while numbers outside of that range tend to be either under-or-over-stable.

== Failure ==

There is a fantastic NAR case study, "Launching Safely in the 21st Century", written by the Special Committee on Range Operation and Procedure which goes into rigorous statistical analysis of rocket failures. The following categories are common failure modes recorded from the fight log database of the Minnesota Amateur Spacemodeler Association (MASA, NAR 576):

'''Unstable.''' The rocket flies with at least part of the boost phase in a nose-down attitude. For
the purposes of this study, based on the goal to characterize unsafe events, comments such
as "kind of unstable" were not counted, nor were "horizontal", "cruise missile", or "coning"
flights (unless they resulted in a crash; see below).

'''Lawn dart.''' The rocket descends in ballistic flight with the nose cone still on. This category
includes "No ejection" and a few "power prangs". Some rockets are designed to do this and
these flights were not counted. Boosters on two stage rockets also did this.

'''Separation.''' The rocket descends in multiple parts with at least one part not slowed by a
recovery device. For the purposes of this study, the few flights with a comment of "stripped
chute" were included here. The unplanned ejection of motor casings should also have been
collected here, but MASA LCOs almost never recorded them as outcomes.

'''Motor CATO.''' The motor failures catastrophically at ignition or during boost. The nature of
the CATO (spit nozzle, forward closure failure, blow by, etc.) was sometimes recorded, but
not consistently.

'''Core sample.''' The rocket descends in ballistic flight, but with the nose cone off the rocket
and acting as a (not very effective) streamer. These events typically have lower impact
speeds, and higher surface areas at impact, than do lawn darts.

'''Motor unrestrained.''' The motor exits the rocket at ignition or during boost (thankfully, this
was rare).

'''Shred.''' The rocket comes apart during ascent, other than by design.

'''No chute.''' The rocket descends without a recovery device deployed, but is not ballistic. This
category does not include chutes that were described as merely tangled, although it is likely
that some LCOs write "no chute" in those circumstances. The rationale here is that if the
LCO described the result as "No chute", it was potentially unsafe.

These would be called "recordable incidents" in the jargon of safety professionals.
When more than one failure occurred during a flight (e.g., unstable flight leading to lawn dart), the
most severe event was recorded.

== Motor Specs ==

Solid rocket motors have a fairly standardized labeling system. On the casing (or reload) itself there is a three-part code which denotes what the total impulse range is, the average thrust, and the delay grain length. All these numbers are in standard metric units.

The letter designation represents the total impulse. Each letter category represents double the total impulse of the previous letter category.

[[File:L1_Guide_Motor_Classification.png|300px|thumb|frame|center|Letter designations increase total impulse exponentially]]

Motor classification table:

[[File:MotorClassification.png|300px|thumb|center|Motor Classification]]

===Motor Designation Breakdown===
To better understand how to read a motor label lets take an example:

'''Aerotech H550ST-14A'''

Here is the spec sheet for this motor[http://www.aerotech-rocketry.com/uploads/4e952284-bb4b-4943-8904-9a0719e8ee3a_AT%20H550ST%20SU%20jun%2019.pdf]. This is the motor that SSI uses for its L1 certification launches.

*'''H''': the letter designating the impulse range. For an H this is from 160 Ns - 320 Ns.
*'''550''': denotes that the motor's average thrust is 550 N.
*'''ST''': denotes what type of propellant is in the casing. In this case, ST stands for "Super Thunder". Aerotech has various names for their different types of propellants, however, often these names are only denoting the color of the flame rather than the chemical compounds that it is made of.
*'''14''': denotes that the motor will fire its ejection charge 14 s after burnout unless it is adjusted, as indicated by the A. Motor delay times can be adjusted with a motor delay tool (otherwise known as a proprietary screwdriver, here is a link to buy one[http://www.buyrocketmotors.com/aerotech-universal-delay-drilling-tool-for-dms-motors/]).

== Recovery ==

[[File:L1_Guide_Delay_Charge.png|thumb|165px|right|Motor delay charge]]
Recovery is the second stage of a simple non-complex rocket, aka basic L1. Although it would seem like the largest percentage of failure would happen during ascent, 75% of failed rockets are a result of a faulty recovery system. Common points of failure for an L1 are: the parachute did not deploy out of the airframe, the parachute deployed too soon before or too far after apogee, line tangling, and too quick of a descent. All of these aspects are things that you should consider when compiling your recovery system.

For L1 all a rocketeer needs is single stage deployment. Simply put, only a main parachute is required to bring the rocket safely back to the ground. Because it is single stage, the parachute should be ejected as close to apogee as possible to prevent unnecessary damage to the rocket. Apogee is the highest point of a rocket trajectory, where the vertical velocity is momentarily zero and the rocket transitions from ascent to descent. This is the point at which the rocket is moving slowest and thus is the most ideal for deployment of a parachute.

For typical L1 rockets, after the motor burns through its main propellant, it burns through a delay grain. This is a slow-burning section at the end of the motor which acts as a timer. Once it has burned through the delay grain, the flame front ignites an ejection charge loaded in the charge well at the front of the motor. This ejection charge, typically black powder, pressurizes the body tube of the rocket and forces the nose cone out, along with the parachute. To test whether your nose cone has the proper fit (tight enough to stay on during flight but loose enough to eject for recovery), hold the back end of your completed, and unloaded, rocket to your mouth and blow hard with a good seal. The nose cone and parachute should both pop out. If you are incapable of doing this, another test can be done by vigorously shaking the rocket by holding the nosecone. The nosecone should separate from the rocket by doing this.

== Simulations ==

[[File:exampleOpenRocket.jpg|thumb|right|300px|Example of the OpenRocket interface]]

It is always important to know what your rocket will do (assuming that things go according to plan), and we use a program called OpenRocket to find the flight profile of our rockets. The program is free, and can be found here[http://openrocket.sourceforge.net/]

OpenRocket is quite easy to learn, and is quite accurate for sub-Mach rockets (those that fly faster should use RasAero to model drag forces.) OpenRocket includes ascent, including a massive database of thrust curves, as well as a simulated descent using the parachutes included in the rocket. If used properly, it can output data from height of apogee to time of flight to drift distance, all of which are incredibly useful while designing your rocket. (Hint: the center of pressure calculation is extremely important.)

One other program of note is called FinSim, which can model possible vibrations within fins. If unchecked, these vibrations can grow and shear the fins off, likely dooming the rocket. The program is required for transonic and supersonic flights, and can be found here[http://www.aerorocket.com/finsim.html]

{{reflist}}

[[Category: Rockets]]

Mission Control

2016-10-04T05:28:42Z

Iangomez: /* Location */

=Location=
[[File:Durand_450_Location.PNG]]

File:Durand 450 Location.PNG

2016-10-04T05:28:14Z

Iangomez: Current location of MC

Current location of MC

How to Join SSI

2016-10-04T05:25:02Z

Iangomez: Changed form to sign up

Hello! There are a few things you need to do if you'd like to have full access to SSI's resources as a member.

=Becoming an official member=

# Pay dues ($10) to one of our financial officers - Evan Long or Nate Simon can accept the dues.
# In order to allow you access to our workspace, [[Mission Control]], you need to do the following things:
##Log into [https://axess.sahr.stanford.edu/ AXESS] and click "STARS" at the top
##Using either the "All Learning" list, or the Search Catalog, complete the following three safety trainings: '''EHS-4200: General Safety, Injury Prevention (IIPP), and Emergency Preparedness, EHS-1900: Chemical Safety for Laboratories, and EHS-2200: Compressed Gas Safety.'''
##Some time after completion, you will receive an email for each of these (can take up to 24 hours) certifying your completion. Save each e-mail as a PDF, or, less preferably, screenshot it. This PDF or screenshot '''must''' have your name on it.
##Sign into the [http://internal.stanfordssi.org/trainings internal site] and under EH&S Safety Training, upload PDFs or screenshots proving your completion of the safety trainings.
##Attend a safety tour of MC. [https://docs.google.com/spreadsheets/d/1n4HBXtpOF_5vcevDjLNPQv4V4OyrZPs6im7FKDkLDJw/edit#gid=0 Sign up for a slot on this form]. (Or ask Elizabeth Hillstrom or John Dean for details.)
# Fill out [https://docs.google.com/a/stanford.edu/forms/d/e/1FAIpQLSesFRAbj9AWz6_tKHVAYKACvCQ4b3Gt9a3lyWpjh4vScXOBPg/viewform this form] so we can add you to our official roster!

=Resources=

Here are some resources that will get you up to speed and on the same page with us:

==The Wiki==

This wiki is a great place to find guides, overviews, and generally useful documentation on SSI projects. Many of the most current plans and docs are in the drive though.

==[https://drive.google.com/open?id=0B5ethK6WQZfAWXgtR25KOEloN2M SSI Drive]==

The drive contains a lot of important documentation for each team. We are trying to put more emphasis on using the wiki as a place for longer-term knowledge storage.

== [https://ssi-teams.slack.com/ Slack] ==

Slack is the lifeblood of SSI. It is a messaging client that allows everyone within SSI to communicate. There are general channels (like {{slack-channel|rockets}}), which allow us to push out general updates to everyone interested in the rockets team and direct messages which allows one to one or smaller group communication. Notifications are pushed directly to your phone/computer/anything that has internet so that way we can infringe on all of your free time!

[https://ssi-teams.slack.com/signup ''Join the SSI Slack here.'']

== [[Mission Control]] ==

Mission Control can be considered the temple to SSI’s religion, the hub, nerve center, or kernel of all project activity. Located in Durand 390, Mission Control houses work sessions and project storage. Note: keycode access is required to the room. For specific questions, contact MC Hammer: Austin Pineault. Meetings or work sessions can also be conducted in the conference room, Durand 393 (often available), or Durand 450 (with prior reservation through AA Department Office on the second floor of Durand).

How to Join SSI

2016-10-04T05:23:52Z

Iangomez: /* Becoming an official member */ added the link to the safety sign up sheet

Hello! There are a few things you need to do if you'd like to have full access to SSI's resources as a member.

=Becoming an official member=

# Pay dues ($10) to one of our financial officers - Evan Long or Nate Simon can accept the dues.
# In order to allow you access to our workspace, [[Mission Control]], you need to do the following things:
##Log into [https://axess.sahr.stanford.edu/ AXESS] and click "STARS" at the top
##Using either the "All Learning" list, or the Search Catalog, complete the following three safety trainings: '''EHS-4200: General Safety, Injury Prevention (IIPP), and Emergency Preparedness, EHS-1900: Chemical Safety for Laboratories, and EHS-2200: Compressed Gas Safety.'''
##Some time after completion, you will receive an email for each of these (can take up to 24 hours) certifying your completion. Save each e-mail as a PDF, or, less preferably, screenshot it. This PDF or screenshot '''must''' have your name on it.
##Sign into the [http://internal.stanfordssi.org/trainings internal site] and under EH&S Safety Training, upload PDFs or screenshots proving your completion of the safety trainings.
##Attend a safety tour of MC. [https://docs.google.com/spreadsheets/d/1n4HBXtpOF_5vcevDjLNPQv4V4OyrZPs6im7FKDkLDJw/edit#gid=0 Sign up for a slot on this form]. (Or ask Elizabeth Hillstrom or John Dean for details.)
# Fill out [https://docs.google.com/a/stanford.edu/forms/d/1oEce1IJ4rjkahWssPCOXkLLQ09tI5gt5WyFoCPXeTUc/viewform this form] so we can add you to our official roster!

=Resources=

Here are some resources that will get you up to speed and on the same page with us:

==The Wiki==

This wiki is a great place to find guides, overviews, and generally useful documentation on SSI projects. Many of the most current plans and docs are in the drive though.

==[https://drive.google.com/open?id=0B5ethK6WQZfAWXgtR25KOEloN2M SSI Drive]==

The drive contains a lot of important documentation for each team. We are trying to put more emphasis on using the wiki as a place for longer-term knowledge storage.

== [https://ssi-teams.slack.com/ Slack] ==

Slack is the lifeblood of SSI. It is a messaging client that allows everyone within SSI to communicate. There are general channels (like {{slack-channel|rockets}}), which allow us to push out general updates to everyone interested in the rockets team and direct messages which allows one to one or smaller group communication. Notifications are pushed directly to your phone/computer/anything that has internet so that way we can infringe on all of your free time!

[https://ssi-teams.slack.com/signup ''Join the SSI Slack here.'']

== [[Mission Control]] ==

Mission Control can be considered the temple to SSI’s religion, the hub, nerve center, or kernel of all project activity. Located in Durand 390, Mission Control houses work sessions and project storage. Note: keycode access is required to the room. For specific questions, contact MC Hammer: Austin Pineault. Meetings or work sessions can also be conducted in the conference room, Durand 393 (often available), or Durand 450 (with prior reservation through AA Department Office on the second floor of Durand).

How to Join SSI

2016-10-04T05:05:15Z

Iangomez:

Hello! There are a few things you need to do if you'd like to have full access to SSI's resources as a member.

=Becoming an official member=

# Pay dues ($10) to one of our financial officers - Evan Long or Nate Simon can accept the dues.
# In order to allow you access to our workspace, [[Mission Control]], you need to do the following things:
##Log into [https://axess.sahr.stanford.edu/ AXESS] and click "STARS" at the top
##Using either the "All Learning" list, or the Search Catalog, complete the following three safety trainings: '''EHS-4200: General Safety, Injury Prevention (IIPP), and Emergency Preparedness, EHS-1900: Chemical Safety for Laboratories, and EHS-2200: Compressed Gas Safety.'''
##Some time after completion, you will receive an email for each of these (can take up to 24 hours) certifying your completion. Save each e-mail as a PDF, or, less preferably, screenshot it. This PDF or screenshot '''must''' have your name on it.
##Sign into the [http://internal.stanfordssi.org/trainings internal site] and under EH&S Safety Training, upload PDFs or screenshots proving your completion of the safety trainings.
##Attend a safety tour of MC. Ask Elizabeth Hillstrom or John Dean for details.
# Fill out [https://docs.google.com/a/stanford.edu/forms/d/1oEce1IJ4rjkahWssPCOXkLLQ09tI5gt5WyFoCPXeTUc/viewform this form] so we can add you to our official roster!

=Resources=

Here are some resources that will get you up to speed and on the same page with us:

==The Wiki==

This wiki is a great place to find guides, overviews, and generally useful documentation on SSI projects. Many of the most current plans and docs are in the drive though.

==[https://drive.google.com/open?id=0B5ethK6WQZfAWXgtR25KOEloN2M SSI Drive]==

The drive contains a lot of important documentation for each team. We are trying to put more emphasis on using the wiki as a place for longer-term knowledge storage.

== [https://ssi-teams.slack.com/ Slack] ==

Slack is the lifeblood of SSI. It is a messaging client that allows everyone within SSI to communicate. There are general channels (like {{slack-channel|rockets}}), which allow us to push out general updates to everyone interested in the rockets team and direct messages which allows one to one or smaller group communication. Notifications are pushed directly to your phone/computer/anything that has internet so that way we can infringe on all of your free time!

[https://ssi-teams.slack.com/signup ''Join the SSI Slack here.'']

== [[Mission Control]] ==

Mission Control can be considered the temple to SSI’s religion, the hub, nerve center, or kernel of all project activity. Located in Durand 390, Mission Control houses work sessions and project storage. Note: keycode access is required to the room. For specific questions, contact MC Hammer: Austin Pineault. Meetings or work sessions can also be conducted in the conference room, Durand 393 (often available), or Durand 450 (with prior reservation through AA Department Office on the second floor of Durand).

Mission Control

2016-09-18T03:10:55Z

Iangomez:

=Location=
Insert picture here

How to Join SSI

2016-09-18T02:21:55Z

Iangomez: Changed a couple of sentences, up to date now.

Hello! There are a few things you need to do if you'd like to have full access to SSI's resources as a member.

=Becoming an official member=

# Pay dues ($10) to one of our financial officers - Ian Gomez, Elizabeth Hillstrom, Evan Long or Nate Simon can accept the dues.
# In order to allow you access to our workspace, [[Mission Control]], you need to do the following things:
##Go to [https://axess.sahr.stanford.edu/ AXESS] and click "STARS" at the top
##Using either the "All Learning" list, or the Search Catalog, complete the following three safety trainings: '''EHS-4200: General Safety, Injury Prevention (IIPP), and Emergency Preparedness, EHS-1900: Chemical Safety for Laboratories, and EHS-2200: Compressed Gas Safety.'''
##Some time after completion, you will receive an email for each of these (can take up to 24 hours) certifying your completion. Save each e-mail as a PDF, or, less preferably, screenshot it. This PDF or screenshot '''must''' have your name on it.
##Create a folder on the [https://drive.google.com/folderview?id=0B7R_UB6uk1UAdWVLM1pURWxyMDA&usp=drive_web SSI Google Drive] with your full name, and, inside of it, upload PDF's or screenshots proving your completion of the safety trainings.
# Fill out [https://docs.google.com/a/stanford.edu/forms/d/1oEce1IJ4rjkahWssPCOXkLLQ09tI5gt5WyFoCPXeTUc/viewform this form] so we can add you to our official roster!

=Resources=

Here are some resources that will get you up to speed and on the same page with us:

==The Wiki==

This wiki is a great place to find guides, overviews, and generally useful documentation on SSI projects. Many of the most current plans and docs are in the drive though.

==[https://drive.google.com/open?id=0B5ethK6WQZfAWXgtR25KOEloN2M SSI Drive]==

The drive contains a lot of important documentation for each team. We are trying to put more emphasis on using the wiki as a place for longer-term knowledge storage.

== [https://ssi-teams.slack.com/ Slack] ==

Slack is the lifeblood of SSI. It is a messaging client that allows everyone within SSI to communicate. There are general channels (like #rockets), which allow us to push out general updates to everyone interested in the rockets team and direct messages which allows one to one or smaller group communication. Notifications are pushed directly to your phone/computer/anything that has internet so that way we can infringe on all of your free time!

[https://ssi-teams.slack.com/signup ''Join the SSI Slack here.'']

== [[Mission Control]] ==

Mission Control can be considered the temple to SSI’s religion, the hub, nerve center, or kernel of all project activity. Located in Durand 390, Mission Control houses work sessions and project storage. Note: keycode access is required to the room. For specific questions, contact MC Hammer: Austin Pineault. Meetings or work sessions can also be conducted in the conference room, Durand 393 (often available), or Durand 450 (with prior reservation through AA Department Office on the second floor of Durand).

Category:Aerodynamics

2016-05-01T05:32:23Z

Iangomez: for practically useful aero

[[Category:Rockets]]

Launch Day

2016-04-02T00:28:09Z

Iangomez: /* Rocket Fuel */ multicolumn

= Who You Will Meet =

== Range Safety Officer (RSO) ==

The RSO is responsible for pre-flight inspection and approval of hobby rocket vehicles within a specified motor impulse range. They give the final word on whether your rocket will launch. Jump to [[#Range Safety Check | Range Safety Check ]] to read about what you need to prepare for inspection or read this document [https://www.nar.org/wp-content/uploads/2014/05/RSO-Operations-Manual-Blue-Mtn-Rktrs.pdf] if you're interested in the nuts and bolts of what an RSO does.

== Launch Control Officer (LCO) ==

The LCO is responsible for control of the range and the actual launching of the rocket vehicles themselves.

= What You Need To Bring =

== Rocket Fuel ==
Note: these lists have two columns.

<div style="column-count:2;-moz-column-count:2;-webkit-column-count:2">
*Ziploc bags to store the things below in.
*Epoxy
*Tools to apply epoxy (i.e. popsicle sticks and paper plates)
*Power Drill and Impact Driver
*Correct drill bits and heads
*Dremel
*Igniters
*Bolts (what kind?)
*Screwdrivers
*Adjustable spanner
*Masking and duct tape
*Sandpaper (120 grit)
*Measuring tape
*Calipers
*Paper Towels
*Plastic bags
*Clamps
*Scale
*Gloves
*Trash bags
</div>
If doing L2 also bring these things along:
<div style="column-count:2;-moz-column-count:2;-webkit-column-count:2">
*Wire strippers
*Wire
*Small needlenose pliers
*Pyrodex
*Centrifuge tubes
*Extra igniters and ematches
*Soldering iron
*Power supply
*Rosin solder
*Altimeters
*Altimeter USB cables
*Batteries
*Battery connectors
*Multimeter
*Precision Screwdriver
*Laptops with altimeter programming software
*Ziptie gun & zipties
</div>

== People Fuel ==

[[File:TCCRebeccasLaunch.jpg|thumb|right|300px|Rebecca Wong at a November launch at TCC]]

*Cases of water
*Cooler for drinks
*Snacks (bring your own food)
*Cash for launch fees and purchasing miscellaneous parts
*Nice cameras
*Inverters and power strips for power from car
*Sharpies and pens
*Pre-filled out documentation
*First aid kits
*Tent
*Chairs
*Folding tables
*Trash bags
*Table cloth

== Appropriate Clothing ==

These requirements obviously change per season, but the running theme is that you will be exposed to the elements all day.
*Sunglasses
*Hats
*Scarves
*Pants
*Walking boots or sneakers
*Rain boots (for walking in muddy farmland)
*Jacket

= Vendors =

[http://bayarearocketry.com/ Bay Area Rocketry] is a local supplier of rocket parts and motors, and will often travel to launches, allowing us to pick up our motors at the site. Since SSI does not store motors on campus, this is a very nice perk.

[https://www.apogeerockets.com/ Apogee Rockets] is a website selling everything from guides to motors to fiberglass tubing, and are a very good starting point for any rocket-related parts.

[https://giantleaprocketry.com/ Giant Leap Rocketry] has a large selection of components, and tends to stock parts for larger rockets. They also sell the Firestorm 54 kit, which we have used extensively.

[https://www.publicmissiles.com Public Missiles] sells very large components - think rockets with diameters >6in.

= Range Layout =

Depending on which launch site you go to, this will be different. However, there are some basic themes.

The main areas of a launching range are the launch pad and control tent, and the parking area. Most high powered rocketry ranges have at least one launch pad that is set up 100ft away from the control tent, a distance specified by the NFPA, section 1127, as the "Minimum Personnel Distance" for any non-complex motor under 1,280 Ns (J motor). However, quite a few ranges also have a second pad, 300ft away, to be able to launch an L motor rocket, or any complex motor combinations up to J motors.

The control tent is where you check in your rocket with the RSO, and get your pad assignment from the LCO. This is also where you can take your L2 exam, if you have not done so already, and also where you bring your rocket back to get your certification.

[[File:Snow_Ranch_Launch_Site.jpg|thumb|frame|center|1000px|Snow Ranch launch site (LUNAR)]]

[[File:Del_Norte_Launch_Site.jpg|thumb|frame|center|1000px|Del Norte launch site (TCC)]]

= Packing Your Parachute =

When packing your parachute it should not fit too tightly within your airframe. You can test this yourself by giving a quick pull on the shock cord attached to the parachute. For the L1s, and most of the L2s, the parachutes are small enough that you should be able to have the entire parachute pop out of the airframe by doing this. If you find yourself having trouble either inserting your parachute into your airframe, removing it, or simply have no idea where to start there are a couple of styles of folding that may help.

'''''Half Fold:''''' This style is recommended if you have a relatively skinny airframe and are not concerned about airframe space.

'''''Triple Fold:''''' This style of folding results in a slightly thicker packed 'chute but it has a shorter length than the half fold.

Diagrams*

Here is a video.*

Some other techniques you may want to try:
*folding your lines in with your 'chute rather than wrapping them around the 'chute
*taping the folded lines with a bit of masking tape to act as a way of creating a "slider" to help slow the opening of the parachute. This essentially creates a faux dual deploy to help reduce recovery drift.

Don't forget to wrap the bottom end of your parachute in a heat resistant cloth like Nomex or Kevlar to prevent the ejection charge from burning holes into your parachute.

Re-do the parachute tied to the screw on metal loop 12 inches below the nose cone. Unscrew the loop, remove the cords and loop the parachute in a simple knot around the loop by passing the parachute through the loops of the cord lines.

Lay the parachute on the ground and arrange it so where all the cords come off the parachute are in the same spot. Accordian fold the parachute like a shirt. It should end with a width of about the diameter of the rocket.

Make a z-fold the long way on the parachute, if it looks like it will be too long for the chute protector, make 2 or 3 z-folds. Lay the cord lines along the chute the long ways and then fold the chute over once along the line of the cords. The cords should not go down the entire way, pull them out through the fold about half an inch from the bottom. Now wrap the cord lines around the chute, taking care to not cross the lines with each other.

Once that is done, take the chute protector and burrito wrap it around the chute. Make sure the slit that the shock cord goes through is at the spot furthest away from where the fire will be.

Fire + Parachute = Very Bad

The parachute+kevlar should act as a plug in the airframe. If the motor ejection does not push the parachute and kevlar out of the airframe, the pressure will push the nose cone out, which will pull the parachute and kevlar out. Both cases are fine.

This folding technique is courtesy of Stue, who learned it from a guy that makes parachutes for the military. We will assume that if it is good enough for the military, it is good enough for us.

Shock cord should be 5 body lengths, rather than 3 body lengths.

= Prepping Your Motor =

If using a single use motor or Disposable Motor System, make sure to check that the delay on the ejection charge is correct using a simulation software (i.e. OpenRocket). If needed adjust the length of the delay grain. Then place the correct quantity of ejection propellant in the correct location. Cap it.

Here is a great video to watch.

= Filling Out Your Flight Card =

You must fill out a flight card before launching any rockets on launch day. You must know and indicate:

[[File:NARLaunchCard.png|thumb|right|200px|NAR Flight Card]]

*Your name
*Model's name as well as whether it is a kit, plan, or original
*What type of recovery is on-board (i.e. parachute, helicopter, streamer, etc.)
*How many stages and engines are on-board
*What the payload is
*What type of rod is needed
*The motor specs: manufacturer, type, impulse, how many, total impulse if multiple

= Range Safety Check =

Before you get cleared for launch, the RSO will inspect your rocket structures, motor certification, and dynamic properties. You should be prepared to answer any and all questions the RSO may have about your rocket. Remember -- the RSO has the final say on whether your rocket gets to launch or not, so it is in your best interest to prepare beforehand all the necessary paperwork, calculations, safety procedures, and proper assembly and convince the RSO you know what you are doing and your launch is unlikely to fail. A full documentation of what the RSO does (or doesn't) do can be found under [[#Range Safety Officer | Range Safety Officer]].

== Administrative ==
*'''Is the flier over 18 years of age?''' If you are not over 18, you legally cannot launch mid or high power rockets. Sorry.

*'''Is the flier certified to the power level being flown?''' Not really an issue for L1's since you have no certification (yet) and will not be attempting to use any motors that require a certification, but if you are flying a motor that requires a high power certification later on, you '''must bring your NAR/TRA membership card''' indicating your current membership and certification level.

*'''Will the flight of the model rocket vehicle “bust” the launch site's FAA waiver?''' This is very important. You must be able to anticipate the altitude your rocket will fly to and be prepared to show simulation data if asked for it. For a single motor, you may be denied a launch if you expect to reach within 15% of the waiver height (15,000' for LUNAR and 16,800' for TCC). This won't be an issue for L1's, but you will certainly be asked what your rocket's expected apogee is, and you better be prepared to answer with an accurate model to back your number.

*'''Will the rocket penetrate cloud cover?''' In accordance with Federal Aviation Regulations (FAR) (the FAA regulations pertaining to who can or can't use airspace), high power rockets cannot be launched into cloud cover greater than 50% or visibility less than 5 miles.

== Motors ==

*'''Is the motor certified?''' NAR, TRA, and NFPA Safety Codes require that only certified motors be used. Motors are certified by undergoing testing as set forth by the NFPA. TRA and NAR have a reciprocity agreement so that motors that are certified with one organization are upheld by the other. Main takeaway: make sure your motor is certified (it will be) and would be good to know which organization did the certification [http://www.thrustcurve.org/searchpage.jsp (easily looked up online)].

*'''What is the motor type, average thrust, and rocket weight? Is the delay time approximate for rocket?''' Motors may be single-use or reloadable, and can be solid, liquid, or hybrids. SSI currently only uses solid motors. Your L1 motor will likely be a single-use motor as these are less prone to errors in assembly that can occur with reloadable casings. The rule of thumb regarding motor selection is a 5-to-1 thrust-to-weight ratio. The motor delay should be set appropriately for the rocket configuration and weather conditions. Motors with longer delays have lower weight recommendations so be sure to run simulations and have a good idea of what delay you need on launch day.

*'''Is the igniter a low-current igniter?''' '''''DO NOT USE LOW-CURRENT IGNITERS FOR YOUR MOTOR IGNITION.''''' I repeat. '''''DO NOT USE LOW-CURRENT IGNITERS FOR YOUR MOTOR IGNITION.''''' Low-current igniters, as their name suggest, ignite with very little current -- so little in fact that the continuity test can set them off. This means that if you do not follow this ''very important warning'', you could end up in a situation where you put your rocket on the rails, connect up the leads, go to press the button for continuity and '''''BAMMMMM''''' YOUR ROCKET GOES FLYING OFF IN FRONT OF YOUR FACE. '''''DO NOT USE LOW-CURRENT IGNITERS FOR YOUR MOTOR IGNITION''''' AKA '''NO Electric Matches'''. E-matches are ok for ejection charges in avionics bays (for L2s+), but they should '''NOT''' be used for motor ignition.

*'''Does your rocket motor have the ejection charge installed?''' This involves pouring a small amount of ejection charge into the top of your motor and putting a cap on it. Do not forget to do this. People have forgotten before (apparently) so don't let that be you, otherwise you'll find your rocket will go up quickly, and then proceed to come down ''very'' quickly. And dangerously. And you won't get certified. So don't forget.

*'''Is sufficient wadding/Kevlar installed?''' Wadding, sometimes referred to as dog barf, is fire-retardant, blown-cellulose insulation (used in home insulation) that protects your rocket/shock cord/parachute protector from getting blown to smithereens by your ejection charge. The Kevlar pads in the Firestorm kits serve an equivalent purpose of protector your parachutes from getting fried. Be sure the Kevlar pad fully wraps around the area of your parachute that is facing the ejection charge. Use your head on this one -- what good is a Kevlar covering, if it isn't covering the part of your parachute that is going to get blasted with BP/Pyrodex?

*'''What kind of motor retention system is installed?''' Motors can be retained with either a friction fit (not recommended) or a positive retention system such as motor clips or retaining rings (what you'll be using for Firestorms). Examine the motor retainer and retaining rings carefully and make sure the smaller ring is sitting inside the groove of the retainer, not just pressed into the retainer anywhere. Give your motor a good pull (the RSO may do this also) and make sure the motor cannot fall out in anyway.

*'''What prevents the motor from flying-through the rocket?''' Give your motor a good push (the RSO may do this also) and make sure neither the motor nor the motor tube move inside the airframe.

== Rocket Construction & Inspection==

*'''Is the rocket stable? Is the CG in front of the CP? Be able to identify both.''' You can find the CG of the rocket with the motor installed by finding its balancing point. Mark this point on the outside of your rocket. Use a simulation program to determine where your CP is and mark this on the outside also. The CG must be at least 1 caliber in front of the CP.

*'''Is the nose cone fitted correctly?''' Check the fit of your nose cone by yourself first. Does the nose cone separate from the rocket under its own weight? It shouldn't. Add a little bit of tape around the shoulder. The right fit is such that the nose cone will not detach if you simply pick up your rocket by the nose cone, but not so tight that you need to exert excessive effort to remove it. A few strong shakes should do the trick. Also check that paint is not inside the body tube or on the shoulder, which can cause the issues with sliding the nose cone off -- sand things down carefully as needed.

*'''Launch lugs and/or rail guides properly installed, positioned, and aligned?''' Verify your rail guides are attached securely and are in good condition (no cracks, deformations, etc). Check for any paint build up that could interfere with the launch rails -- sand as needed.

*'''Are the fins in good condition and mounted parallel to the roll axis?''' Verify you epoxied your fins on straight. Wiggle the fins at the tip. Do your fins move or flex a lot? They shouldn't. Examine the fins for any cracks or warpage.

*'''Is an appropriately-sized recovery system installed and attached?''' Verify that your shock cord is not frayed, burnt, or cut and that all knots are secure and will not slip out. Pull on the shock cord several times to check it is secured to your airframe properly. Check all your quick links and any other hardware are tightened completely and will not separate under load. Check that your parachute is in good condition and is not loose, burnt, or cut. Double check your Kevlar wrapping.

*'''Are there vent holes?''' Vent holes are used to vent the rocket's internal pressure and avoid premature separation. You should have two vent holes, one in the aft section of your rocket and one in the forward, near the nose cone.

== Launch Pad Procedure ==

The rocket should slide freely on the rail. The pad angle should be within 20 degrees of the vertical axis (normal to the surface of the earth). Flight critical electronics (if there are any) should be armed before putting in igniters. Any radio control equipment should also be nominally operating before arming the igniters.

== How to install an igniter ==

Place in the nozzle of rocket, and tape the igniter to the rocket so it does not slide out. '''Make sure not to short the leads of the igniters. '''

Here is a great video to watch.

= Checklist of What to Know =

'''If you do not know the answer to any part of this, look it up. Either in the above sections, or on the internet.'''

- How to answer questions about the bolts attaching the coupler

- How high will your rocket go? Use your own measurements of the rocket and plug them into openRocket. Don't use other peoples calculations.

- How fast will your rocket go? Same as above.

- Where is your CP?

- Where is the CG?

- How fast the rocket is going off the launch pad?

- Model of motor?

- Impulse of motor?

- Thrust of motor?

- Burn time of motor?

- Stability margin?

- What epoxy was used in construction? Ans - 30 min epoxy for the tube fins and JB Weld for hardpoint and motor retainer.

= Quick G Calculation =

Quick way to calculate g’s on liftoff:
Take the average thrust of motor in N, divide by 5 to get lbs, divide by the weight of your rocket, you want to aim for around 5 - 6 g’s.

The H550 motor puts us at an initial launch acceleration of 30g’s, approximately 90 ft/s off the launch rod, so anything inside the tube will shake uncontrollably and possibly break. It will also cause the parachutes and other stuff in the rocket to be shoved down the tube. Be careful about how you attach the coupler as screws can catch the parachute and make it fail. Ask Ian on how to explain this to the safety officer!

=Final Check!=
Are you ready to launch? Run through this quick checklist!

==L1==
*Is your parachute packed correctly? Kevlar wrapped around? Is it attached to your rocket?
*Is your airframe bolted together nice and tight?
*Did you buy the correct motor? (H or I Motor - MUST BE 38mm)
*Did you pack in black powder for motor delay ejections? Check the delay time.
*Does your nose cone slide off with vigorous vertical shaking (with the motor assembled)
*Is there any epoxy that has not dried? (Wait if there is)
*Is your certification form and flight card filled out with rocket info? Do you know your NAR/TRA membership #?
*Did you pay your launch fee?
*Are your rail guides properly mounted on your rocket?
*Is there a pressure ventilation hole so your recovery system doesn't prematurely deploy?

==L2==
In addition to the last 6 items listed under the L1 check,

*Are your parachutes correctly packed and attached to the avionics bay (and nose cone)?
*Did you buy the correct motor? (J or K -- if you're not using motor ejection, don't fill with black powder)
*Are all electronics functioning? Fresh batteries? Easy switch access?
*If using a barometric-based altimeter, have you drilled a pressure-access hole for it?
*Have you loaded up your charge wells?
*Have you checked the position and attachment of your igniters?
*'''Are your apogee and main charges facing the correct direction?'''

All good? Great! Get a photo of you and your rocket on the launch pad and good luck!

[[Category:Rockets]]

Launch Day

2016-04-01T23:59:19Z

Iangomez: /* Rocket Fuel */

= Who You Will Meet =

== Range Safety Officer (RSO) ==

The RSO is responsible for pre-flight inspection and approval of hobby rocket vehicles within a specified motor impulse range. They give the final word on whether your rocket will launch. Jump to [[#Range Safety Check | Range Safety Check ]] to read about what you need to prepare for inspection or read this document [https://www.nar.org/wp-content/uploads/2014/05/RSO-Operations-Manual-Blue-Mtn-Rktrs.pdf] if you're interested in the nuts and bolts of what an RSO does.

== Launch Control Officer (LCO) ==

The LCO is responsible for control of the range and the actual launching of the rocket vehicles themselves.

= What You Need To Bring =

== Rocket Fuel ==

*Ziploc bags to store the things below in.
*Epoxy
*Tools to apply epoxy (i.e. popsicle sticks and paper plates)
*Power Drill and Impact Driver
*Correct drill bits and heads
*Dremel
*Igniters
*Bolts (what kind?)
*Screwdrivers
*Adjustable spanner
*Masking and duct tape
*Sandpaper (120 grit)
*Measuring tape
*Calipers
*Paper Towels
*Plastic bags
*Clamps
*Scale
*Gloves
*Trash bags

If doing L2 also bring these things along:

*Wire strippers
*Wire
*Small needlenose pliers
*Pyrodex
*Centrifuge tubes
*Extra igniters and ematches
*Soldering iron
*Power supply
*Rosin solder
*Altimeters
*Altimeter USB cables
*Batteries
*Battery connectors
*Multimeter
*Precision Screwdriver
*Laptops with altimeter programming software
*Ziptie gun & zipties

== People Fuel ==

[[File:TCCRebeccasLaunch.jpg|thumb|right|300px|Rebecca Wong at a November launch at TCC]]

*Cases of water
*Cooler for drinks
*Snacks (bring your own food)
*Cash for launch fees and purchasing miscellaneous parts
*Nice cameras
*Inverters and power strips for power from car
*Sharpies and pens
*Pre-filled out documentation
*First aid kits
*Tent
*Chairs
*Folding tables
*Trash bags
*Table cloth

== Appropriate Clothing ==

These requirements obviously change per season, but the running theme is that you will be exposed to the elements all day.
*Sunglasses
*Hats
*Scarves
*Pants
*Walking boots or sneakers
*Rain boots (for walking in muddy farmland)
*Jacket

= Vendors =

[http://bayarearocketry.com/ Bay Area Rocketry] is a local supplier of rocket parts and motors, and will often travel to launches, allowing us to pick up our motors at the site. Since SSI does not store motors on campus, this is a very nice perk.

[https://www.apogeerockets.com/ Apogee Rockets] is a website selling everything from guides to motors to fiberglass tubing, and are a very good starting point for any rocket-related parts.

[https://giantleaprocketry.com/ Giant Leap Rocketry] has a large selection of components, and tends to stock parts for larger rockets. They also sell the Firestorm 54 kit, which we have used extensively.

[https://www.publicmissiles.com Public Missiles] sells very large components - think rockets with diameters >6in.

= Range Layout =

Depending on which launch site you go to, this will be different. However, there are some basic themes.

The main areas of a launching range are the launch pad and control tent, and the parking area. Most high powered rocketry ranges have at least one launch pad that is set up 100ft away from the control tent, a distance specified by the NFPA, section 1127, as the "Minimum Personnel Distance" for any non-complex motor under 1,280 Ns (J motor). However, quite a few ranges also have a second pad, 300ft away, to be able to launch an L motor rocket, or any complex motor combinations up to J motors.

The control tent is where you check in your rocket with the RSO, and get your pad assignment from the LCO. This is also where you can take your L2 exam, if you have not done so already, and also where you bring your rocket back to get your certification.

[[File:Snow_Ranch_Launch_Site.jpg|thumb|frame|center|1000px|Snow Ranch launch site (LUNAR)]]

[[File:Del_Norte_Launch_Site.jpg|thumb|frame|center|1000px|Del Norte launch site (TCC)]]

= Packing Your Parachute =

When packing your parachute it should not fit too tightly within your airframe. You can test this yourself by giving a quick pull on the shock cord attached to the parachute. For the L1s, and most of the L2s, the parachutes are small enough that you should be able to have the entire parachute pop out of the airframe by doing this. If you find yourself having trouble either inserting your parachute into your airframe, removing it, or simply have no idea where to start there are a couple of styles of folding that may help.

'''''Half Fold:''''' This style is recommended if you have a relatively skinny airframe and are not concerned about airframe space.

'''''Triple Fold:''''' This style of folding results in a slightly thicker packed 'chute but it has a shorter length than the half fold.

Diagrams*

Here is a video.*

Some other techniques you may want to try:
*folding your lines in with your 'chute rather than wrapping them around the 'chute
*taping the folded lines with a bit of masking tape to act as a way of creating a "slider" to help slow the opening of the parachute. This essentially creates a faux dual deploy to help reduce recovery drift.

Don't forget to wrap the bottom end of your parachute in a heat resistant cloth like Nomex or Kevlar to prevent the ejection charge from burning holes into your parachute.

Re-do the parachute tied to the screw on metal loop 12 inches below the nose cone. Unscrew the loop, remove the cords and loop the parachute in a simple knot around the loop by passing the parachute through the loops of the cord lines.

Lay the parachute on the ground and arrange it so where all the cords come off the parachute are in the same spot. Accordian fold the parachute like a shirt. It should end with a width of about the diameter of the rocket.

Make a z-fold the long way on the parachute, if it looks like it will be too long for the chute protector, make 2 or 3 z-folds. Lay the cord lines along the chute the long ways and then fold the chute over once along the line of the cords. The cords should not go down the entire way, pull them out through the fold about half an inch from the bottom. Now wrap the cord lines around the chute, taking care to not cross the lines with each other.

Once that is done, take the chute protector and burrito wrap it around the chute. Make sure the slit that the shock cord goes through is at the spot furthest away from where the fire will be.

Fire + Parachute = Very Bad

The parachute+kevlar should act as a plug in the airframe. If the motor ejection does not push the parachute and kevlar out of the airframe, the pressure will push the nose cone out, which will pull the parachute and kevlar out. Both cases are fine.

This folding technique is courtesy of Stue, who learned it from a guy that makes parachutes for the military. We will assume that if it is good enough for the military, it is good enough for us.

Shock cord should be 5 body lengths, rather than 3 body lengths.

= Prepping Your Motor =

If using a single use motor or Disposable Motor System, make sure to check that the delay on the ejection charge is correct using a simulation software (i.e. OpenRocket). If needed adjust the length of the delay grain. Then place the correct quantity of ejection propellant in the correct location. Cap it.

Here is a great video to watch.

= Filling Out Your Flight Card =

You must fill out a flight card before launching any rockets on launch day. You must know and indicate:

[[File:NARLaunchCard.png|thumb|right|200px|NAR Flight Card]]

*Your name
*Model's name as well as whether it is a kit, plan, or original
*What type of recovery is on-board (i.e. parachute, helicopter, streamer, etc.)
*How many stages and engines are on-board
*What the payload is
*What type of rod is needed
*The motor specs: manufacturer, type, impulse, how many, total impulse if multiple

= Range Safety Check =

Before you get cleared for launch, the RSO will inspect your rocket structures, motor certification, and dynamic properties. You should be prepared to answer any and all questions the RSO may have about your rocket. Remember -- the RSO has the final say on whether your rocket gets to launch or not, so it is in your best interest to prepare beforehand all the necessary paperwork, calculations, safety procedures, and proper assembly and convince the RSO you know what you are doing and your launch is unlikely to fail. A full documentation of what the RSO does (or doesn't) do can be found under [[#Range Safety Officer | Range Safety Officer]].

== Administrative ==
*'''Is the flier over 18 years of age?''' If you are not over 18, you legally cannot launch mid or high power rockets. Sorry.

*'''Is the flier certified to the power level being flown?''' Not really an issue for L1's since you have no certification (yet) and will not be attempting to use any motors that require a certification, but if you are flying a motor that requires a high power certification later on, you '''must bring your NAR/TRA membership card''' indicating your current membership and certification level.

*'''Will the flight of the model rocket vehicle “bust” the launch site's FAA waiver?''' This is very important. You must be able to anticipate the altitude your rocket will fly to and be prepared to show simulation data if asked for it. For a single motor, you may be denied a launch if you expect to reach within 15% of the waiver height (15,000' for LUNAR and 16,800' for TCC). This won't be an issue for L1's, but you will certainly be asked what your rocket's expected apogee is, and you better be prepared to answer with an accurate model to back your number.

*'''Will the rocket penetrate cloud cover?''' In accordance with Federal Aviation Regulations (FAR) (the FAA regulations pertaining to who can or can't use airspace), high power rockets cannot be launched into cloud cover greater than 50% or visibility less than 5 miles.

== Motors ==

*'''Is the motor certified?''' NAR, TRA, and NFPA Safety Codes require that only certified motors be used. Motors are certified by undergoing testing as set forth by the NFPA. TRA and NAR have a reciprocity agreement so that motors that are certified with one organization are upheld by the other. Main takeaway: make sure your motor is certified (it will be) and would be good to know which organization did the certification [http://www.thrustcurve.org/searchpage.jsp (easily looked up online)].

*'''What is the motor type, average thrust, and rocket weight? Is the delay time approximate for rocket?''' Motors may be single-use or reloadable, and can be solid, liquid, or hybrids. SSI currently only uses solid motors. Your L1 motor will likely be a single-use motor as these are less prone to errors in assembly that can occur with reloadable casings. The rule of thumb regarding motor selection is a 5-to-1 thrust-to-weight ratio. The motor delay should be set appropriately for the rocket configuration and weather conditions. Motors with longer delays have lower weight recommendations so be sure to run simulations and have a good idea of what delay you need on launch day.

*'''Is the igniter a low-current igniter?''' '''''DO NOT USE LOW-CURRENT IGNITERS FOR YOUR MOTOR IGNITION.''''' I repeat. '''''DO NOT USE LOW-CURRENT IGNITERS FOR YOUR MOTOR IGNITION.''''' Low-current igniters, as their name suggest, ignite with very little current -- so little in fact that the continuity test can set them off. This means that if you do not follow this ''very important warning'', you could end up in a situation where you put your rocket on the rails, connect up the leads, go to press the button for continuity and '''''BAMMMMM''''' YOUR ROCKET GOES FLYING OFF IN FRONT OF YOUR FACE. '''''DO NOT USE LOW-CURRENT IGNITERS FOR YOUR MOTOR IGNITION''''' AKA '''NO Electric Matches'''. E-matches are ok for ejection charges in avionics bays (for L2s+), but they should '''NOT''' be used for motor ignition.

*'''Does your rocket motor have the ejection charge installed?''' This involves pouring a small amount of ejection charge into the top of your motor and putting a cap on it. Do not forget to do this. People have forgotten before (apparently) so don't let that be you, otherwise you'll find your rocket will go up quickly, and then proceed to come down ''very'' quickly. And dangerously. And you won't get certified. So don't forget.

*'''Is sufficient wadding/Kevlar installed?''' Wadding, sometimes referred to as dog barf, is fire-retardant, blown-cellulose insulation (used in home insulation) that protects your rocket/shock cord/parachute protector from getting blown to smithereens by your ejection charge. The Kevlar pads in the Firestorm kits serve an equivalent purpose of protector your parachutes from getting fried. Be sure the Kevlar pad fully wraps around the area of your parachute that is facing the ejection charge. Use your head on this one -- what good is a Kevlar covering, if it isn't covering the part of your parachute that is going to get blasted with BP/Pyrodex?

*'''What kind of motor retention system is installed?''' Motors can be retained with either a friction fit (not recommended) or a positive retention system such as motor clips or retaining rings (what you'll be using for Firestorms). Examine the motor retainer and retaining rings carefully and make sure the smaller ring is sitting inside the groove of the retainer, not just pressed into the retainer anywhere. Give your motor a good pull (the RSO may do this also) and make sure the motor cannot fall out in anyway.

*'''What prevents the motor from flying-through the rocket?''' Give your motor a good push (the RSO may do this also) and make sure neither the motor nor the motor tube move inside the airframe.

== Rocket Construction & Inspection==

*'''Is the rocket stable? Is the CG in front of the CP? Be able to identify both.''' You can find the CG of the rocket with the motor installed by finding its balancing point. Mark this point on the outside of your rocket. Use a simulation program to determine where your CP is and mark this on the outside also. The CG must be at least 1 caliber in front of the CP.

*'''Is the nose cone fitted correctly?''' Check the fit of your nose cone by yourself first. Does the nose cone separate from the rocket under its own weight? It shouldn't. Add a little bit of tape around the shoulder. The right fit is such that the nose cone will not detach if you simply pick up your rocket by the nose cone, but not so tight that you need to exert excessive effort to remove it. A few strong shakes should do the trick. Also check that paint is not inside the body tube or on the shoulder, which can cause the issues with sliding the nose cone off -- sand things down carefully as needed.

*'''Launch lugs and/or rail guides properly installed, positioned, and aligned?''' Verify your rail guides are attached securely and are in good condition (no cracks, deformations, etc). Check for any paint build up that could interfere with the launch rails -- sand as needed.

*'''Are the fins in good condition and mounted parallel to the roll axis?''' Verify you epoxied your fins on straight. Wiggle the fins at the tip. Do your fins move or flex a lot? They shouldn't. Examine the fins for any cracks or warpage.

*'''Is an appropriately-sized recovery system installed and attached?''' Verify that your shock cord is not frayed, burnt, or cut and that all knots are secure and will not slip out. Pull on the shock cord several times to check it is secured to your airframe properly. Check all your quick links and any other hardware are tightened completely and will not separate under load. Check that your parachute is in good condition and is not loose, burnt, or cut. Double check your Kevlar wrapping.

*'''Are there vent holes?''' Vent holes are used to vent the rocket's internal pressure and avoid premature separation. You should have two vent holes, one in the aft section of your rocket and one in the forward, near the nose cone.

== Launch Pad Procedure ==

The rocket should slide freely on the rail. The pad angle should be within 20 degrees of the vertical axis (normal to the surface of the earth). Flight critical electronics (if there are any) should be armed before putting in igniters. Any radio control equipment should also be nominally operating before arming the igniters.

== How to install an igniter ==

Place in the nozzle of rocket, and tape the igniter to the rocket so it does not slide out. '''Make sure not to short the leads of the igniters. '''

Here is a great video to watch.

= Checklist of What to Know =

'''If you do not know the answer to any part of this, look it up. Either in the above sections, or on the internet.'''

- How to answer questions about the bolts attaching the coupler

- How high will your rocket go? Use your own measurements of the rocket and plug them into openRocket. Don't use other peoples calculations.

- How fast will your rocket go? Same as above.

- Where is your CP?

- Where is the CG?

- How fast the rocket is going off the launch pad?

- Model of motor?

- Impulse of motor?

- Thrust of motor?

- Burn time of motor?

- Stability margin?

- What epoxy was used in construction? Ans - 30 min epoxy for the tube fins and JB Weld for hardpoint and motor retainer.

= Quick G Calculation =

Quick way to calculate g’s on liftoff:
Take the average thrust of motor in N, divide by 5 to get lbs, divide by the weight of your rocket, you want to aim for around 5 - 6 g’s.

The H550 motor puts us at an initial launch acceleration of 30g’s, approximately 90 ft/s off the launch rod, so anything inside the tube will shake uncontrollably and possibly break. It will also cause the parachutes and other stuff in the rocket to be shoved down the tube. Be careful about how you attach the coupler as screws can catch the parachute and make it fail. Ask Ian on how to explain this to the safety officer!

=Final Check!=
Are you ready to launch? Run through this quick checklist!

==L1==
*Is your parachute packed correctly? Kevlar wrapped around? Is it attached to your rocket?
*Is your airframe bolted together nice and tight?
*Did you buy the correct motor? (H or I Motor - MUST BE 38mm)
*Did you pack in black powder for motor delay ejections? Check the delay time.
*Does your nose cone slide off with vigorous vertical shaking (with the motor assembled)
*Is there any epoxy that has not dried? (Wait if there is)
*Is your certification form and flight card filled out with rocket info? Do you know your NAR/TRA membership #?
*Did you pay your launch fee?
*Are your rail guides properly mounted on your rocket?
*Is there a pressure ventilation hole so your recovery system doesn't prematurely deploy?

==L2==
In addition to the last 6 items listed under the L1 check,

*Are your parachutes correctly packed and attached to the avionics bay (and nose cone)?
*Did you buy the correct motor? (J or K -- if you're not using motor ejection, don't fill with black powder)
*Are all electronics functioning? Fresh batteries? Easy switch access?
*If using a barometric-based altimeter, have you drilled a pressure-access hole for it?
*Have you loaded up your charge wells?
*Have you checked the position and attachment of your igniters?
*'''Are your apogee and main charges facing the correct direction?'''

All good? Great! Get a photo of you and your rocket on the launch pad and good luck!

[[Category:Rockets]]

Solidworks

2016-04-01T23:47:13Z

Iangomez:

[[File:Solidworks_logo.png | 200 px | right]]
This page will assist you in installing Solidworks on your personal computer.
[[Category: Rockets]]

== How to Install SolidWorks on your MacBook ==

=== Installing Windows on Your Mac ===
SolidWorks only runs on Windows operating systems, so you have a couple of options to install Windows on your Mac. You can either partition your hard drive or use a 3rd party virtualization software. Using a 3rd party virtualization software allows you to run Windows as an application on your Mac OS, but can slow down your laptop significantly, so I’d recommend partitioning your hard drive.

You might (or might not - depending on your computer) need a blank USB drive in order to partition your hard drive. You’ll also probably need at least around 30 gb of free space on your hard drive, but may be able to get away with less - consider the size of SolidWorks, Windows, any other programs you want to install on your Windows OS, and projects you create in SolidWorks.

Apple has a program called BootCamp that will help you partition your drive and install windows. This guide should have most of the information you need: [https://support.apple.com/en-us/HT201468 How to install Windows using BootCamp].

For step 2 of this guide, you can get a free version of Windows 10 from Stanford Licensing. Follow these steps:

1. Make sure you’re using Chrome, not Safari, as your web browser.

2. go to: [https://uit.stanford.edu/service/softwarelic Stanford Software Licensing]

3. click on the blue button that says “Software Licensing Web Store”

4. click on the Microsoft tab and then on Windows 10 Education and add it to your cart

5. download the 64-bit version to your computer and it should pop up in your downloads folder as “Win10_Academic_English_x64.iso”

One of the steps in the guide includes opening Apple Bootcamp application on your computer, which itself gives you specific directions that can vary from computer to computer.

After you have your hard drive partitioned and you can switch between Mac OS and Windows (If you’re in Windows and want to switch to Mac OS, click on the Bootcamp System tray item which is at the bottom right of your screen. If you’re in Mac OS and want to go to Windows, do a Spotlight search for “Startup Disk” which you can also find in System Preferences, “click the lock to make changes” and enter your password, then click BOOTCAMP Windows and “Restart…”).

===Installing SolidWorks===
Now you’ll need to actually install SolidWorks. The Terman Engineering Library (which is on the 2nd floor of the Huang Engineering building) has free copies of SolidWorks on USBs that you can borrow for up to 4 hours.

The USB will have a PDF with directions on how to install SolidWorks in addition to the actual program, so make sure you follow those directions carefully. It will probably take about an hour to do the whole installation. (Don’t forget to bring your laptop charger to the library because installing it uses a lot of battery!)

Once you have SolidWorks installed, you won’t actually be able to save anything you make until you put it into compatibility mode, so it can run with Windows 10. To do this, go under properties and set it to run on Windows 8 compatibility mode.

[[Category:CFD]]

Solidworks

2016-04-01T23:46:50Z

Iangomez: added logo

[File:Solidworks_logo.png | 200 px | right]
This page will assist you in installing Solidworks on your personal computer.
[[Category: Rockets]]

== How to Install SolidWorks on your MacBook ==

=== Installing Windows on Your Mac ===
SolidWorks only runs on Windows operating systems, so you have a couple of options to install Windows on your Mac. You can either partition your hard drive or use a 3rd party virtualization software. Using a 3rd party virtualization software allows you to run Windows as an application on your Mac OS, but can slow down your laptop significantly, so I’d recommend partitioning your hard drive.

You might (or might not - depending on your computer) need a blank USB drive in order to partition your hard drive. You’ll also probably need at least around 30 gb of free space on your hard drive, but may be able to get away with less - consider the size of SolidWorks, Windows, any other programs you want to install on your Windows OS, and projects you create in SolidWorks.

Apple has a program called BootCamp that will help you partition your drive and install windows. This guide should have most of the information you need: [https://support.apple.com/en-us/HT201468 How to install Windows using BootCamp].

For step 2 of this guide, you can get a free version of Windows 10 from Stanford Licensing. Follow these steps:

1. Make sure you’re using Chrome, not Safari, as your web browser.

2. go to: [https://uit.stanford.edu/service/softwarelic Stanford Software Licensing]

3. click on the blue button that says “Software Licensing Web Store”

4. click on the Microsoft tab and then on Windows 10 Education and add it to your cart

5. download the 64-bit version to your computer and it should pop up in your downloads folder as “Win10_Academic_English_x64.iso”

One of the steps in the guide includes opening Apple Bootcamp application on your computer, which itself gives you specific directions that can vary from computer to computer.

After you have your hard drive partitioned and you can switch between Mac OS and Windows (If you’re in Windows and want to switch to Mac OS, click on the Bootcamp System tray item which is at the bottom right of your screen. If you’re in Mac OS and want to go to Windows, do a Spotlight search for “Startup Disk” which you can also find in System Preferences, “click the lock to make changes” and enter your password, then click BOOTCAMP Windows and “Restart…”).

===Installing SolidWorks===
Now you’ll need to actually install SolidWorks. The Terman Engineering Library (which is on the 2nd floor of the Huang Engineering building) has free copies of SolidWorks on USBs that you can borrow for up to 4 hours.

The USB will have a PDF with directions on how to install SolidWorks in addition to the actual program, so make sure you follow those directions carefully. It will probably take about an hour to do the whole installation. (Don’t forget to bring your laptop charger to the library because installing it uses a lot of battery!)

Once you have SolidWorks installed, you won’t actually be able to save anything you make until you put it into compatibility mode, so it can run with Windows 10. To do this, go under properties and set it to run on Windows 8 compatibility mode.

[[Category:CFD]]

File:Solidworks logo.png

2016-04-01T23:44:09Z

Iangomez:

Solidworks

2016-04-01T23:41:59Z

Iangomez:

This page will assist you in installing Solidworks on your personal computer.
[[Category: Rockets]]

== How to Install SolidWorks on your MacBook ==

=== Installing Windows on Your Mac ===
SolidWorks only runs on Windows operating systems, so you have a couple of options to install Windows on your Mac. You can either partition your hard drive or use a 3rd party virtualization software. Using a 3rd party virtualization software allows you to run Windows as an application on your Mac OS, but can slow down your laptop significantly, so I’d recommend partitioning your hard drive.

You might (or might not - depending on your computer) need a blank USB drive in order to partition your hard drive. You’ll also probably need at least around 30 gb of free space on your hard drive, but may be able to get away with less - consider the size of SolidWorks, Windows, any other programs you want to install on your Windows OS, and projects you create in SolidWorks.

Apple has a program called BootCamp that will help you partition your drive and install windows. This guide should have most of the information you need: [https://support.apple.com/en-us/HT201468 How to install Windows using BootCamp].

For step 2 of this guide, you can get a free version of Windows 10 from Stanford Licensing. Follow these steps:

1. Make sure you’re using Chrome, not Safari, as your web browser.

2. go to: [https://uit.stanford.edu/service/softwarelic Stanford Software Licensing]

3. click on the blue button that says “Software Licensing Web Store”

4. click on the Microsoft tab and then on Windows 10 Education and add it to your cart

5. download the 64-bit version to your computer and it should pop up in your downloads folder as “Win10_Academic_English_x64.iso”

One of the steps in the guide includes opening Apple Bootcamp application on your computer, which itself gives you specific directions that can vary from computer to computer.

After you have your hard drive partitioned and you can switch between Mac OS and Windows (If you’re in Windows and want to switch to Mac OS, click on the Bootcamp System tray item which is at the bottom right of your screen. If you’re in Mac OS and want to go to Windows, do a Spotlight search for “Startup Disk” which you can also find in System Preferences, “click the lock to make changes” and enter your password, then click BOOTCAMP Windows and “Restart…”).

===Installing SolidWorks===
Now you’ll need to actually install SolidWorks. The Terman Engineering Library (which is on the 2nd floor of the Huang Engineering building) has free copies of SolidWorks on USBs that you can borrow for up to 4 hours.

The USB will have a PDF with directions on how to install SolidWorks in addition to the actual program, so make sure you follow those directions carefully. It will probably take about an hour to do the whole installation. (Don’t forget to bring your laptop charger to the library because installing it uses a lot of battery!)

Once you have SolidWorks installed, you won’t actually be able to save anything you make until you put it into compatibility mode, so it can run with Windows 10. To do this, go under properties and set it to run on Windows 8 compatibility mode.

[[Category:CFD]]

Firestorm AV Bay

2016-04-01T02:21:15Z

Iangomez:

{{problems}}

{{rocket-stub}}

[[Category: Rockets]]
[[Category: Avionics]]

The Avionics Bay in a rocket provides a place to mount all electronic equipment while protecting it from any pyrotechnics used during the flight of the rocket. The most basic AV bay used by SSI is the firestorm AV bay, which is primarily used to house an altimeter for duel-deploy for an L2 certification flight. (Need to add a nice picture of an AV bay here)

=Structure=

The picture to the left shows the general structure of an AV bay. The mounting rack provide the surfaces for mounting hardware. The bulkheads (also called end caps) protect the equipment from ejection charges and provide a surface for mounting charge wells and connection points to the shock cord. The all threads clamp the AV bay together and provide the rigid elements that prevent to AV bay from being ripped apart during ejection. The coupler encapsulates the AV bay while providing a structural element to connect the two halves of the rocket's air frame.

===Bulkheads and mounting rack===

The solid works files of the AV bay, and an already made SLDDRW file for exporting the parts to be laser cut can be found here: [https://workbench.grabcad.com/workbench/projects/gc_EDWRalY4J7crz16PdmSYkSs-3GFHSB6B2Aix13CTMa8#/space/gcTokGZ9oUjQ-YkQ5yyFbxrsyW5Cwm67B_WzILmZotkSz4 GrabCad Files]

The bulkheads and mounting racks are typically made of laser cut duron. This is for easy of manufacturing, low cost, strength, and resistance to cracking. Each bulkhead consists of an inner and an outer piece to ensure that so that the securely fit into the coupler. The inner and outer pieces for each bulkhead are epoxied together, as shown in the images to the left. The pegs of the mounting rack fit into the slots on the inner bulkhead. On one side, the bulkhead should be epoxied to the bulkhead (this is typically the end of the AV that is facing the ground when it is mounted in the rocket). Also attached to each bulkhead is a an eye bolt, for attaching to the shock cord on either side, and a charge well. Two more holes should be drilled through each bulkhead for igniter wires to be routed through.

'''NOTE:''' Completely assemble the structural components of the of the AV bay, with the mounting rack, bulkheads, and coupler put clamped together, and all of the holes on the bulkheads lined up ''before'' epoxying anything, to make sure that every piece is oreiented correctly, then disassemble and epoxy. This is easier than you might think to mess up.

===Couple and All threads===

=Mounting Avionics=

'''NOTE:''' The specific electronics used in an AV bay often differ, so there is no single best way to mount everything. Before drilling holes or permanently attaching anything, lay out all of the components and make sure that you have enough room. '''Remember that there are all threads running on each side of the mounting rack, so make sure there is space for them when mounting electronics.''' Also, remember that wires are actually a thing, so plan space for them. Think about how you will close up the AV bay with wires attached to the top and bottom bulk head. ''Think everything through before mounting stuff.''

===Altimeter===

While each type of Altemeter are mounted slightly differently, they should all be mounted with screws and spaces, or standoffs. Place the altimeter on the mounting rack where it will be mounted, and mark where the

===Batteries===

===Pin Switch===

Pointwise

2016-03-30T23:24:51Z

Iangomez:

This page will help you navigate the finer points of Pointwise and act as a guide if SSI needs one.

[http://www.cfd-online.com/Wiki/Meshing Go here if you want to learn more about meshing in general.]

[https://www.youtube.com/playlist?list=PLHdUEgvTk9VXtMvfg_pUDsiVQl_uQhyrO Someone please watch these]

=Overview=
#Import the native SolidWorks file.
#Check the integrity of the solid model.
#Reorganize surfaces prior to meshing.
#Set mesh defaults.
#Mesh the model.
#Adjust resolution of particular surface meshes.
#Assemble the unstructured block.
#Generate the volume mesh using T-Rex.
#Set CAE boundary conditions.
#Export the CAE file.

CAE = Computer aided engineering

=Importing a Solidworks File=
Importing native CAD is the same process as importing neutral CAD formats in Pointwise. From the File menu, select Import, Database. Pointwise recognizes the correct format based on the file extension. In this case, SolidWorks part files end with .sldprt.

The model size tolerance is an important consideration when importing CAD files into Pointwise. We recommend adjusting the model size tolerance to within about an order of magnitude of the largest spatial dimension of the geometry. This parameter is found in the File menu under Properties. Setting the appropriate model size tolerance helps Pointwise's geometry kernel interpret and process the geometric information with the highest possible degree of accuracy. In order to maintain maximum integrity, this step must be performed prior to importing the geometry. If you do not know the actual model size, import the geometry using the default model size tolerance, record the value from the File, Properties panel, undo the import, set the appropriate model size tolerance and re-import the CAD file.

=Check Integrity of Solid Model=
Pointwise can import the solid model and exploit the information it contains about how the surfaces are stitched together. Even when using native CAD files, it is a good idea to check to see if the solid model is watertight. This is carried out in the Create, Assemble, Models panel by selecting the model and clicking Assemble. If the solid model is watertight, there should be a single model (all surfaces green) and zero lamina boundaries (red edges). If the solid model is not watertight, the tolerance can be increased to automatically close the gaps.

=Reorganize Surfaces=
Quite often the arrangement of the surfaces created by the CAD software is not optimal for meshing. For example, the body of the filter tube is made up of four surfaces, but we probably only need one surface mesh patch to represent the whole tube. The complementary capability to Pointwise's solid modeling is quilting. Quilting allows the user to redefine the meshing regions from the original CAD surfaces to something more meaningful. In the filter tube example, we want Pointwise to create one surface mesh patch on all four filter tube surfaces. This is accomplished by quilting the four surfaces into one logical meshing region. By not requiring the grid boundaries to follow all the CAD topology, we end up with a simpler grid topology and higher mesh quality.

The quilt assembly feature has the ability to automatically assemble the quilts based on an angle criterion. The angle is defined as angular deviation between the normals of the adjacent surfaces.

=Sources=
[http://www.pointwise.com/theconnector/July-2012/CAD-to-CFD-in-5-Minutes.shtml Adapted from ''From CAD to CFD in Five Minutes: The Complete Story of Meshing a Real Geometry Using Pointwise'']

[http://www.pointwise.com/DIY/ DIY Pointwise Instructions]

[https://www.youtube.com/watch?v=5ze94LiODjw Getting Past the Blank Screen] Great tutorial for a 2D NACA airfoil.

[https://www.youtube.com/watch?v=JIj97iUCB5Q SU2-Pointwise Workshop: Surface and Volume Meshing]

=Command Cheat Sheet=

Note: This guide is only for Windows.

Legend: RMB=Right Mouse Button, LMB=Left Mouse Button, MMB=Middle Mouse Button

==File==
New - Ctrl + N

Open - Ctrl + O

Save - Ctrl + S

Save As - Ctrl + Shift + S

Print to File Setup - Ctrl + Shift + P

Print to File - Ctrl + P
==Edit==
Undo - Ctrl + Z

Redo - Ctrl + Y

Cut - Ctrl + X

Copy - Ctrl + C

Paste - Ctrl + V

Delete - Delete

Delete Special - Ctrl + Delete

Project - Ctrl + Shift + J

Split - Ctrl + Q

Join - Ctrl + J

==View==
Zoom, Undo Zoom - Ctrl + F2

Zoom, Zoom to Fit - F2

Zoom, Zoom to Selection - Shift + F2

Manage Views, Recall View 1 - Ctrl + 1

Manage Views, Recall View 2 - Ctrl + 2

Manage Views, Recall View 3 - Ctrl + 3

Manage Views, Recall View 4 - Ctrl + 4

Manage Views, Recall View 5 - Ctrl + 5

Manage Views, Recall View 6 - Ctrl + 6

Manage Views, Save View 1 - Alt + 1

Manage Views, Save View 2 - Alt + 2

Manage Views, Save View 3 - Alt + 3

Manage Views, Save View 4 - Alt + 4

Manage Views, Save View 5 - Alt + 5

Manage Views, Save View 6 - Alt + 6

Set Rotation Point - Ctrl + Shift + Right Mouse Button

Reset, View - Ctrl + R

Reset, Pan - Ctrl + U

Reset, Rotation Point - Ctrl + Shift + R

Demote, Redraw - F5

Show Domains - Ctrl + F3

Show Connectors - Ctrl + F4

Show Nodes - Ctrl + F5

Show Database - Ctrl + Shift + F5

Show Axes - Ctrl + Shift + F3

Show XYZ Axes - Ctrl + Shift + F4

==Select==
Select All - Ctrl + A

Unselect All - Ctrl + D

Toggle Selection - Ctrl + T

Adjacent - Ctrl + Shift + N

All Adjacent - Ctrl + Shift + A

Mask - Ctrl + M

==Create==

Assemble domains without opening the panel - Ctrl + B

Assemble blocks without opening the panel - Ctrl + Shift + B

==Grid==

Dimension - Ctrl + W

Distribute - Ctrl + G

Initialize selected domains/blocks - Ctrl + I

==Script==

Re-Execute - Ctrl + E

==Miscellaneous==

Help - F1

OK - Ctrl + Enter

Cancel - Esc

Apply - Ctrl + Shift + Enter

Clear message window - Ctrl + Shift + Delete

Display point position and distance between it and last selected point - Alt + Right
Mouse Button

Cycle through selectable entities under cursor - Spacebar

Cycle through selectable entities under cursor in reversed order - Ctrl + Spacebar

Mask all except for spacings - F7

Mask all except for blocks - F9

Mask all except for domains - F10

Mask all except for connectors - F11

Mask all except for database - F12

Toggle Entity Mask - Shift + Mask Function Key

Unmask all except for spacings - Ctrl + F7

Unmask all except for blocks - Ctrl + F9

Unmask all except for domains - Ctrl + F10

Unmask all except for connectors - Ctrl + F11

Unmask all except for database - Ctrl + F12

[[Category: Rockets]]
[[Category:CFD]]

Pointwise

2016-03-30T23:18:02Z

Iangomez:

This page will help you navigate the finer points of Pointwise and act as a guide if SSI needs one.

[http://www.cfd-online.com/Wiki/Meshing Go here if you want to learn more about meshing in general.]

=Overview=
#Import the native SolidWorks file.
#Check the integrity of the solid model.
#Reorganize surfaces prior to meshing.
#Set mesh defaults.
#Mesh the model.
#Adjust resolution of particular surface meshes.
#Assemble the unstructured block.
#Generate the volume mesh using T-Rex.
#Set CAE boundary conditions.
#Export the CAE file.

CAE = Computer aided engineering

=Importing a Solidworks File=
Importing native CAD is the same process as importing neutral CAD formats in Pointwise. From the File menu, select Import, Database. Pointwise recognizes the correct format based on the file extension. In this case, SolidWorks part files end with .sldprt.

The model size tolerance is an important consideration when importing CAD files into Pointwise. We recommend adjusting the model size tolerance to within about an order of magnitude of the largest spatial dimension of the geometry. This parameter is found in the File menu under Properties. Setting the appropriate model size tolerance helps Pointwise's geometry kernel interpret and process the geometric information with the highest possible degree of accuracy. In order to maintain maximum integrity, this step must be performed prior to importing the geometry. If you do not know the actual model size, import the geometry using the default model size tolerance, record the value from the File, Properties panel, undo the import, set the appropriate model size tolerance and re-import the CAD file.

=Check Integrity of Solid Model=
Pointwise can import the solid model and exploit the information it contains about how the surfaces are stitched together. Even when using native CAD files, it is a good idea to check to see if the solid model is watertight. This is carried out in the Create, Assemble, Models panel by selecting the model and clicking Assemble. If the solid model is watertight, there should be a single model (all surfaces green) and zero lamina boundaries (red edges). If the solid model is not watertight, the tolerance can be increased to automatically close the gaps.

=Reorganize Surfaces=
Quite often the arrangement of the surfaces created by the CAD software is not optimal for meshing. For example, the body of the filter tube is made up of four surfaces, but we probably only need one surface mesh patch to represent the whole tube. The complementary capability to Pointwise's solid modeling is quilting. Quilting allows the user to redefine the meshing regions from the original CAD surfaces to something more meaningful. In the filter tube example, we want Pointwise to create one surface mesh patch on all four filter tube surfaces. This is accomplished by quilting the four surfaces into one logical meshing region. By not requiring the grid boundaries to follow all the CAD topology, we end up with a simpler grid topology and higher mesh quality.

The quilt assembly feature has the ability to automatically assemble the quilts based on an angle criterion. The angle is defined as angular deviation between the normals of the adjacent surfaces.

=Sources=
[http://www.pointwise.com/theconnector/July-2012/CAD-to-CFD-in-5-Minutes.shtml Adapted from ''From CAD to CFD in Five Minutes: The Complete Story of Meshing a Real Geometry Using Pointwise'']

[http://www.pointwise.com/DIY/ DIY Pointwise Instructions]

[https://www.youtube.com/watch?v=5ze94LiODjw Getting Past the Blank Screen] Great tutorial for a 2D NACA airfoil.

[https://www.youtube.com/watch?v=JIj97iUCB5Q SU2-Pointwise Workshop: Surface and Volume Meshing]

=Command Cheat Sheet=

Note: This guide is only for Windows.

Legend: RMB=Right Mouse Button, LMB=Left Mouse Button, MMB=Middle Mouse Button

==File==
New - Ctrl + N

Open - Ctrl + O

Save - Ctrl + S

Save As - Ctrl + Shift + S

Print to File Setup - Ctrl + Shift + P

Print to File - Ctrl + P
==Edit==
Undo - Ctrl + Z

Redo - Ctrl + Y

Cut - Ctrl + X

Copy - Ctrl + C

Paste - Ctrl + V

Delete - Delete

Delete Special - Ctrl + Delete

Project - Ctrl + Shift + J

Split - Ctrl + Q

Join - Ctrl + J

==View==
Zoom, Undo Zoom - Ctrl + F2

Zoom, Zoom to Fit - F2

Zoom, Zoom to Selection - Shift + F2

Manage Views, Recall View 1 - Ctrl + 1

Manage Views, Recall View 2 - Ctrl + 2

Manage Views, Recall View 3 - Ctrl + 3

Manage Views, Recall View 4 - Ctrl + 4

Manage Views, Recall View 5 - Ctrl + 5

Manage Views, Recall View 6 - Ctrl + 6

Manage Views, Save View 1 - Alt + 1

Manage Views, Save View 2 - Alt + 2

Manage Views, Save View 3 - Alt + 3

Manage Views, Save View 4 - Alt + 4

Manage Views, Save View 5 - Alt + 5

Manage Views, Save View 6 - Alt + 6

Set Rotation Point - Ctrl + Shift + Right Mouse Button

Reset, View - Ctrl + R

Reset, Pan - Ctrl + U

Reset, Rotation Point - Ctrl + Shift + R

Demote, Redraw - F5

Show Domains - Ctrl + F3

Show Connectors - Ctrl + F4

Show Nodes - Ctrl + F5

Show Database - Ctrl + Shift + F5

Show Axes - Ctrl + Shift + F3

Show XYZ Axes - Ctrl + Shift + F4

==Select==
Select All - Ctrl + A

Unselect All - Ctrl + D

Toggle Selection - Ctrl + T

Adjacent - Ctrl + Shift + N

All Adjacent - Ctrl + Shift + A

Mask - Ctrl + M

==Create==

Assemble domains without opening the panel - Ctrl + B

Assemble blocks without opening the panel - Ctrl + Shift + B

==Grid==

Dimension - Ctrl + W

Distribute - Ctrl + G

Initialize selected domains/blocks - Ctrl + I

==Script==

Re-Execute - Ctrl + E

==Miscellaneous==

Help - F1

OK - Ctrl + Enter

Cancel - Esc

Apply - Ctrl + Shift + Enter

Clear message window - Ctrl + Shift + Delete

Display point position and distance between it and last selected point - Alt + Right
Mouse Button

Cycle through selectable entities under cursor - Spacebar

Cycle through selectable entities under cursor in reversed order - Ctrl + Spacebar

Mask all except for spacings - F7

Mask all except for blocks - F9

Mask all except for domains - F10

Mask all except for connectors - F11

Mask all except for database - F12

Toggle Entity Mask - Shift + Mask Function Key

Unmask all except for spacings - Ctrl + F7

Unmask all except for blocks - Ctrl + F9

Unmask all except for domains - Ctrl + F10

Unmask all except for connectors - Ctrl + F11

Unmask all except for database - Ctrl + F12

[[Category: Rockets]]
[[Category:CFD]]

Pointwise

2016-03-30T23:13:52Z

Iangomez: /* Sources */ added youtube

This page will help you navigate the finer points of Pointwise and act as a guide if SSI needs one.

=Overview=
#Import the native SolidWorks file.
#Check the integrity of the solid model.
#Reorganize surfaces prior to meshing.
#Set mesh defaults.
#Mesh the model.
#Adjust resolution of particular surface meshes.
#Assemble the unstructured block.
#Generate the volume mesh using T-Rex.
#Set CAE boundary conditions.
#Export the CAE file.

CAE = Computer aided engineering

=Importing a Solidworks File=
Importing native CAD is the same process as importing neutral CAD formats in Pointwise. From the File menu, select Import, Database. Pointwise recognizes the correct format based on the file extension. In this case, SolidWorks part files end with .sldprt.

The model size tolerance is an important consideration when importing CAD files into Pointwise. We recommend adjusting the model size tolerance to within about an order of magnitude of the largest spatial dimension of the geometry. This parameter is found in the File menu under Properties. Setting the appropriate model size tolerance helps Pointwise's geometry kernel interpret and process the geometric information with the highest possible degree of accuracy. In order to maintain maximum integrity, this step must be performed prior to importing the geometry. If you do not know the actual model size, import the geometry using the default model size tolerance, record the value from the File, Properties panel, undo the import, set the appropriate model size tolerance and re-import the CAD file.

=Check Integrity of Solid Model=
Pointwise can import the solid model and exploit the information it contains about how the surfaces are stitched together. Even when using native CAD files, it is a good idea to check to see if the solid model is watertight. This is carried out in the Create, Assemble, Models panel by selecting the model and clicking Assemble. If the solid model is watertight, there should be a single model (all surfaces green) and zero lamina boundaries (red edges). If the solid model is not watertight, the tolerance can be increased to automatically close the gaps.

=Reorganize Surfaces=
Quite often the arrangement of the surfaces created by the CAD software is not optimal for meshing. For example, the body of the filter tube is made up of four surfaces, but we probably only need one surface mesh patch to represent the whole tube. The complementary capability to Pointwise's solid modeling is quilting. Quilting allows the user to redefine the meshing regions from the original CAD surfaces to something more meaningful. In the filter tube example, we want Pointwise to create one surface mesh patch on all four filter tube surfaces. This is accomplished by quilting the four surfaces into one logical meshing region. By not requiring the grid boundaries to follow all the CAD topology, we end up with a simpler grid topology and higher mesh quality.

The quilt assembly feature has the ability to automatically assemble the quilts based on an angle criterion. The angle is defined as angular deviation between the normals of the adjacent surfaces.

=Sources=
[http://www.pointwise.com/theconnector/July-2012/CAD-to-CFD-in-5-Minutes.shtml Adapted from ''From CAD to CFD in Five Minutes: The Complete Story of Meshing a Real Geometry Using Pointwise'']

[http://www.pointwise.com/DIY/ DIY Pointwise Instructions]

[https://www.youtube.com/watch?v=5ze94LiODjw Getting Past the Blank Screen] Great tutorial for a 2D NACA airfoil.

[https://www.youtube.com/watch?v=JIj97iUCB5Q SU2-Pointwise Workshop: Surface and Volume Meshing]

=Command Cheat Sheet=

Note: This guide is only for Windows.

Legend: RMB=Right Mouse Button, LMB=Left Mouse Button, MMB=Middle Mouse Button

==File==
New - Ctrl + N

Open - Ctrl + O

Save - Ctrl + S

Save As - Ctrl + Shift + S

Print to File Setup - Ctrl + Shift + P

Print to File - Ctrl + P
==Edit==
Undo - Ctrl + Z

Redo - Ctrl + Y

Cut - Ctrl + X

Copy - Ctrl + C

Paste - Ctrl + V

Delete - Delete

Delete Special - Ctrl + Delete

Project - Ctrl + Shift + J

Split - Ctrl + Q

Join - Ctrl + J

==View==
Zoom, Undo Zoom - Ctrl + F2

Zoom, Zoom to Fit - F2

Zoom, Zoom to Selection - Shift + F2

Manage Views, Recall View 1 - Ctrl + 1

Manage Views, Recall View 2 - Ctrl + 2

Manage Views, Recall View 3 - Ctrl + 3

Manage Views, Recall View 4 - Ctrl + 4

Manage Views, Recall View 5 - Ctrl + 5

Manage Views, Recall View 6 - Ctrl + 6

Manage Views, Save View 1 - Alt + 1

Manage Views, Save View 2 - Alt + 2

Manage Views, Save View 3 - Alt + 3

Manage Views, Save View 4 - Alt + 4

Manage Views, Save View 5 - Alt + 5

Manage Views, Save View 6 - Alt + 6

Set Rotation Point - Ctrl + Shift + Right Mouse Button

Reset, View - Ctrl + R

Reset, Pan - Ctrl + U

Reset, Rotation Point - Ctrl + Shift + R

Demote, Redraw - F5

Show Domains - Ctrl + F3

Show Connectors - Ctrl + F4

Show Nodes - Ctrl + F5

Show Database - Ctrl + Shift + F5

Show Axes - Ctrl + Shift + F3

Show XYZ Axes - Ctrl + Shift + F4

==Select==
Select All - Ctrl + A

Unselect All - Ctrl + D

Toggle Selection - Ctrl + T

Adjacent - Ctrl + Shift + N

All Adjacent - Ctrl + Shift + A

Mask - Ctrl + M

==Create==

Assemble domains without opening the panel - Ctrl + B

Assemble blocks without opening the panel - Ctrl + Shift + B

==Grid==

Dimension - Ctrl + W

Distribute - Ctrl + G

Initialize selected domains/blocks - Ctrl + I

==Script==

Re-Execute - Ctrl + E

==Miscellaneous==

Help - F1

OK - Ctrl + Enter

Cancel - Esc

Apply - Ctrl + Shift + Enter

Clear message window - Ctrl + Shift + Delete

Display point position and distance between it and last selected point - Alt + Right
Mouse Button

Cycle through selectable entities under cursor - Spacebar

Cycle through selectable entities under cursor in reversed order - Ctrl + Spacebar

Mask all except for spacings - F7

Mask all except for blocks - F9

Mask all except for domains - F10

Mask all except for connectors - F11

Mask all except for database - F12

Toggle Entity Mask - Shift + Mask Function Key

Unmask all except for spacings - Ctrl + F7

Unmask all except for blocks - Ctrl + F9

Unmask all except for domains - Ctrl + F10

Unmask all except for connectors - Ctrl + F11

Unmask all except for database - Ctrl + F12

[[Category: Rockets]]
[[Category:CFD]]

Pointwise

2016-03-30T22:59:26Z

Iangomez:

This page will help you navigate the finer points of Pointwise and act as a guide if SSI needs one.

=Overview=
#Import the native SolidWorks file.
#Check the integrity of the solid model.
#Reorganize surfaces prior to meshing.
#Set mesh defaults.
#Mesh the model.
#Adjust resolution of particular surface meshes.
#Assemble the unstructured block.
#Generate the volume mesh using T-Rex.
#Set CAE boundary conditions.
#Export the CAE file.

CAE = Computer aided engineering

=Importing a Solidworks File=
Importing native CAD is the same process as importing neutral CAD formats in Pointwise. From the File menu, select Import, Database. Pointwise recognizes the correct format based on the file extension. In this case, SolidWorks part files end with .sldprt.

The model size tolerance is an important consideration when importing CAD files into Pointwise. We recommend adjusting the model size tolerance to within about an order of magnitude of the largest spatial dimension of the geometry. This parameter is found in the File menu under Properties. Setting the appropriate model size tolerance helps Pointwise's geometry kernel interpret and process the geometric information with the highest possible degree of accuracy. In order to maintain maximum integrity, this step must be performed prior to importing the geometry. If you do not know the actual model size, import the geometry using the default model size tolerance, record the value from the File, Properties panel, undo the import, set the appropriate model size tolerance and re-import the CAD file.

=Check Integrity of Solid Model=
Pointwise can import the solid model and exploit the information it contains about how the surfaces are stitched together. Even when using native CAD files, it is a good idea to check to see if the solid model is watertight. This is carried out in the Create, Assemble, Models panel by selecting the model and clicking Assemble. If the solid model is watertight, there should be a single model (all surfaces green) and zero lamina boundaries (red edges). If the solid model is not watertight, the tolerance can be increased to automatically close the gaps.

=Reorganize Surfaces=
Quite often the arrangement of the surfaces created by the CAD software is not optimal for meshing. For example, the body of the filter tube is made up of four surfaces, but we probably only need one surface mesh patch to represent the whole tube. The complementary capability to Pointwise's solid modeling is quilting. Quilting allows the user to redefine the meshing regions from the original CAD surfaces to something more meaningful. In the filter tube example, we want Pointwise to create one surface mesh patch on all four filter tube surfaces. This is accomplished by quilting the four surfaces into one logical meshing region. By not requiring the grid boundaries to follow all the CAD topology, we end up with a simpler grid topology and higher mesh quality.

The quilt assembly feature has the ability to automatically assemble the quilts based on an angle criterion. The angle is defined as angular deviation between the normals of the adjacent surfaces.

=Sources=
[http://www.pointwise.com/theconnector/July-2012/CAD-to-CFD-in-5-Minutes.shtml Adapted from ''From CAD to CFD in Five Minutes: The Complete Story of Meshing a Real Geometry Using Pointwise'']

[http://www.pointwise.com/DIY/ DIY Pointwise Instructions]

=Command Cheat Sheet=

Note: This guide is only for Windows.

Legend: RMB=Right Mouse Button, LMB=Left Mouse Button, MMB=Middle Mouse Button

==File==
New - Ctrl + N

Open - Ctrl + O

Save - Ctrl + S

Save As - Ctrl + Shift + S

Print to File Setup - Ctrl + Shift + P

Print to File - Ctrl + P
==Edit==
Undo - Ctrl + Z

Redo - Ctrl + Y

Cut - Ctrl + X

Copy - Ctrl + C

Paste - Ctrl + V

Delete - Delete

Delete Special - Ctrl + Delete

Project - Ctrl + Shift + J

Split - Ctrl + Q

Join - Ctrl + J

==View==
Zoom, Undo Zoom - Ctrl + F2

Zoom, Zoom to Fit - F2

Zoom, Zoom to Selection - Shift + F2

Manage Views, Recall View 1 - Ctrl + 1

Manage Views, Recall View 2 - Ctrl + 2

Manage Views, Recall View 3 - Ctrl + 3

Manage Views, Recall View 4 - Ctrl + 4

Manage Views, Recall View 5 - Ctrl + 5

Manage Views, Recall View 6 - Ctrl + 6

Manage Views, Save View 1 - Alt + 1

Manage Views, Save View 2 - Alt + 2

Manage Views, Save View 3 - Alt + 3

Manage Views, Save View 4 - Alt + 4

Manage Views, Save View 5 - Alt + 5

Manage Views, Save View 6 - Alt + 6

Set Rotation Point - Ctrl + Shift + Right Mouse Button

Reset, View - Ctrl + R

Reset, Pan - Ctrl + U

Reset, Rotation Point - Ctrl + Shift + R

Demote, Redraw - F5

Show Domains - Ctrl + F3

Show Connectors - Ctrl + F4

Show Nodes - Ctrl + F5

Show Database - Ctrl + Shift + F5

Show Axes - Ctrl + Shift + F3

Show XYZ Axes - Ctrl + Shift + F4

==Select==
Select All - Ctrl + A

Unselect All - Ctrl + D

Toggle Selection - Ctrl + T

Adjacent - Ctrl + Shift + N

All Adjacent - Ctrl + Shift + A

Mask - Ctrl + M

==Create==

Assemble domains without opening the panel - Ctrl + B

Assemble blocks without opening the panel - Ctrl + Shift + B

==Grid==

Dimension - Ctrl + W

Distribute - Ctrl + G

Initialize selected domains/blocks - Ctrl + I

==Script==

Re-Execute - Ctrl + E

==Miscellaneous==

Help - F1

OK - Ctrl + Enter

Cancel - Esc

Apply - Ctrl + Shift + Enter

Clear message window - Ctrl + Shift + Delete

Display point position and distance between it and last selected point - Alt + Right
Mouse Button

Cycle through selectable entities under cursor - Spacebar

Cycle through selectable entities under cursor in reversed order - Ctrl + Spacebar

Mask all except for spacings - F7

Mask all except for blocks - F9

Mask all except for domains - F10

Mask all except for connectors - F11

Mask all except for database - F12

Toggle Entity Mask - Shift + Mask Function Key

Unmask all except for spacings - Ctrl + F7

Unmask all except for blocks - Ctrl + F9

Unmask all except for domains - Ctrl + F10

Unmask all except for connectors - Ctrl + F11

Unmask all except for database - Ctrl + F12

[[Category: Rockets]]
[[Category:CFD]]

Pointwise

2016-03-30T22:57:57Z

Iangomez: /* Command Cheat Sheet */ populated w/keyboard shortcuts

This page will help you navigate the finer points of Pointwise and act as a guide if SSI needs one.

=Overview=
#Import the native SolidWorks file.
#Check the integrity of the solid model.
#Reorganize surfaces prior to meshing.
#Set mesh defaults.
#Mesh the model.
#Adjust resolution of particular surface meshes.
#Assemble the unstructured block.
#Generate the volume mesh using T-Rex.
#Set CAE boundary conditions.
#Export the CAE file.

CAE = Computer aided engineering

=Command Cheat Sheet=

Note: This guide is only for Windows.

Legend: RMB=Right Mouse Button, LMB=Left Mouse Button, MMB=Middle Mouse Button

==File==
New - Ctrl + N
Open - Ctrl + O
Save - Ctrl + S
Save As - Ctrl + Shift + S
Print to File Setup - Ctrl + Shift + P
Print to File - Ctrl + P
==Edit==
Undo - Ctrl + Z
Redo - Ctrl + Y
Cut - Ctrl + X
Copy - Ctrl + C
Paste - Ctrl + V
Delete - Delete
Delete Special - Ctrl + Delete
Project - Ctrl + Shift + J
Split - Ctrl + Q
Join - Ctrl + J
==View==
Zoom, Undo Zoom - Ctrl + F2
Zoom, Zoom to Fit - F2
Zoom, Zoom to Selection - Shift + F2
Manage Views, Recall View 1 - Ctrl + 1
Manage Views, Recall View 2 - Ctrl + 2
Manage Views, Recall View 3 - Ctrl + 3
Manage Views, Recall View 4 - Ctrl + 4
Manage Views, Recall View 5 - Ctrl + 5
Manage Views, Recall View 6 - Ctrl + 6
Manage Views, Save View 1 - Alt + 1
Manage Views, Save View 2 - Alt + 2
Manage Views, Save View 3 - Alt + 3
Manage Views, Save View 4 - Alt + 4
Manage Views, Save View 5 - Alt + 5
Manage Views, Save View 6 - Alt + 6
Set Rotation Point - Ctrl + Shift + Right Mouse Button
Reset, View - Ctrl + R
Reset, Pan - Ctrl + U
Reset, Rotation Point - Ctrl + Shift + R
Demote, Redraw - F5
Show Domains - Ctrl + F3
Show Connectors - Ctrl + F4
Show Nodes - Ctrl + F5
Show Database - Ctrl + Shift + F5
Show Axes - Ctrl + Shift + F3
Show XYZ Axes - Ctrl + Shift + F4
==Select==
Select All - Ctrl + A
Unselect All - Ctrl + D
Toggle Selection - Ctrl + T
Adjacent - Ctrl + Shift + N
All Adjacent - Ctrl + Shift + A
Mask - Ctrl + M
==Create==
Assemble domains without opening the panel - Ctrl + B
Assemble blocks without opening the panel - Ctrl + Shift + B
==Grid==
Dimension - Ctrl + W
Distribute - Ctrl + G
Initialize selected domains/blocks - Ctrl + I
==Script==
Re-Execute - Ctrl + E
==Miscellaneous==
Help - F1
OK - Ctrl + Enter
Cancel - Esc
Apply - Ctrl + Shift + Enter
Clear message window - Ctrl + Shift + Delete
Display point position and distance between it and last selected point - Alt + Right Mouse Button
Cycle through selectable entities under cursor - Spacebar
Cycle through selectable entities under cursor in reversed order - Ctrl + Spacebar
Mask all except for spacings - F7
Mask all except for blocks - F9
Mask all except for domains - F10
Mask all except for connectors - F11
Mask all except for database - F12
Toggle Entity Mask - Shift + Mask Function Key
Unmask all except for spacings - Ctrl + F7
Unmask all except for blocks - Ctrl + F9
Unmask all except for domains - Ctrl + F10
Unmask all except for connectors - Ctrl + F11
Unmask all except for database - Ctrl + F12

=Importing a Solidworks File=
Importing native CAD is the same process as importing neutral CAD formats in Pointwise. From the File menu, select Import, Database. Pointwise recognizes the correct format based on the file extension. In this case, SolidWorks part files end with .sldprt.

The model size tolerance is an important consideration when importing CAD files into Pointwise. We recommend adjusting the model size tolerance to within about an order of magnitude of the largest spatial dimension of the geometry. This parameter is found in the File menu under Properties. Setting the appropriate model size tolerance helps Pointwise's geometry kernel interpret and process the geometric information with the highest possible degree of accuracy. In order to maintain maximum integrity, this step must be performed prior to importing the geometry. If you do not know the actual model size, import the geometry using the default model size tolerance, record the value from the File, Properties panel, undo the import, set the appropriate model size tolerance and re-import the CAD file.

=Check Integrity of Solid Model=
Pointwise can import the solid model and exploit the information it contains about how the surfaces are stitched together. Even when using native CAD files, it is a good idea to check to see if the solid model is watertight. This is carried out in the Create, Assemble, Models panel by selecting the model and clicking Assemble. If the solid model is watertight, there should be a single model (all surfaces green) and zero lamina boundaries (red edges). If the solid model is not watertight, the tolerance can be increased to automatically close the gaps.

=Reorganize Surfaces=
Quite often the arrangement of the surfaces created by the CAD software is not optimal for meshing. For example, the body of the filter tube is made up of four surfaces, but we probably only need one surface mesh patch to represent the whole tube. The complementary capability to Pointwise's solid modeling is quilting. Quilting allows the user to redefine the meshing regions from the original CAD surfaces to something more meaningful. In the filter tube example, we want Pointwise to create one surface mesh patch on all four filter tube surfaces. This is accomplished by quilting the four surfaces into one logical meshing region. By not requiring the grid boundaries to follow all the CAD topology, we end up with a simpler grid topology and higher mesh quality.

The quilt assembly feature has the ability to automatically assemble the quilts based on an angle criterion. The angle is defined as angular deviation between the normals of the adjacent surfaces.
=Sources=
[http://www.pointwise.com/theconnector/July-2012/CAD-to-CFD-in-5-Minutes.shtml Adapted from ''From CAD to CFD in Five Minutes: The Complete Story of Meshing a Real Geometry Using Pointwise'']

[http://www.pointwise.com/DIY/ DIY Pointwise Instructions]

[[Category: Rockets]]
[[Category:CFD]]

Pointwise

2016-03-30T22:47:58Z

Iangomez:

Pointwise

2016-03-30T22:06:51Z

Iangomez: /* Sources */

Pointwise

2016-03-30T22:06:41Z

Iangomez: added DIY link

Pointwise

2016-03-30T21:36:03Z

Iangomez: added check integrity

Pointwise

2016-03-30T21:16:37Z

Iangomez: added info and citation

Pointwise

2016-03-30T21:11:47Z

Iangomez: added overview

Pointwise

2016-03-30T21:01:51Z

Iangomez:

This page will help you navigate the finer points of Pointwise and act as a guide if SSI needs one.

{{rocket-stub}}
[[Category: Rockets]]
[[Category:CFD]]

Solidworks

2016-03-30T21:01:44Z

Iangomez:

This page will assist you in installing Solidworks on your personal computer.
{{rocket-stub}}
[[Category: Rockets]]

== How to Install SolidWorks on your MacBook ==

=== Installing Windows on Your Mac ===
SolidWorks only runs on Windows operating systems, so you have a couple of options to install Windows on your Mac. You can either partition your hard drive or use a 3rd party virtualization software. Using a 3rd party virtualization software allows you to run Windows as an application on your Mac OS, but can slow down your laptop significantly, so I’d recommend partitioning your hard drive.

You might (or might not - depending on your computer) need a blank USB drive in order to partition your hard drive. You’ll also probably need at least around 30 gb of free space on your hard drive, but may be able to get away with less - consider the size of SolidWorks, Windows, any other programs you want to install on your Windows OS, and projects you create in SolidWorks.

Apple has a program called BootCamp that will help you partition your drive and install windows. This guide should have most of the information you need: [https://support.apple.com/en-us/HT201468 How to install Windows using BootCamp].

For step 2 of this guide, you can get a free version of Windows 10 from Stanford Licensing. Follow these steps:

1. Make sure you’re using Chrome, not Safari, as your web browser.

2. go to: [https://uit.stanford.edu/service/softwarelic Stanford Software Licensing]

3. click on the blue button that says “Software Licensing Web Store”

4. click on the Microsoft tab and then on Windows 10 Education and add it to your cart

5. download the 64-bit version to your computer and it should pop up in your downloads folder as “Win10_Academic_English_x64.iso”

One of the steps in the guide includes opening Apple Bootcamp application on your computer, which itself gives you specific directions that can vary from computer to computer.

After you have your hard drive partitioned and you can switch between Mac OS and Windows (If you’re in Windows and want to switch to Mac OS, click on the Bootcamp System tray item which is at the bottom right of your screen. If you’re in Mac OS and want to go to Windows, do a Spotlight search for “Startup Disk” which you can also find in System Preferences, “click the lock to make changes” and enter your password, then click BOOTCAMP Windows and “Restart…”).

===Installing SolidWorks===
Now you’ll need to actually install SolidWorks. The Terman Engineering Library (which is on the 2nd floor of the Huang Engineering building) has free copies of SolidWorks on USBs that you can borrow for up to 4 hours.

The USB will have a PDF with directions on how to install SolidWorks in addition to the actual program, so make sure you follow those directions carefully. It will probably take about an hour to do the whole installation. (Don’t forget to bring your laptop charger to the library because installing it uses a lot of battery!)

Once you have SolidWorks installed, you won’t actually be able to save anything you make until you put it into compatibility mode, so it can run with Windows 10. To do this, go under properties and set it to run on Windows 8 compatibility mode.

[[Category:CFD]]

SU2

2016-03-30T21:01:22Z

Iangomez: created new category

This page will help you with installing SU2, as well as provide specific help with the way we use SU2.
[[File:SU2_Logo.png | right | 300px ]]
[https://github.com/su2code/SU2 Link to the Github code repository for SU2]
[https://github.com/su2code/SU2/wiki Link to the super helpful SU2 wiki (which is also hosted in Github)]

=The Big Picture=
Need to compile the code in order to run the solver. Once compiled for either a serial or multi-core system, you can run the CFD solver. The solver requires two inputs: a mesh grid and a configuration file.

*Will add a few templates once we figure out realistic configuration cases for our rockets.
*Will add a sample mesh once we have one.

=Installation on personal computer=

General Tips:
*Learn how to navigate around your computer using just your terminal
*Understand how to edit .bashrc files
*Understand how to change path variables in your terminal
*If not compiling with cygwin due to some carriage return error, add this to your .bash_profile script (in your home directory)
<code>export SHELLOPTS</code>

<code>set -o igncr</code>

==Windows==
Install cygwin with g++, gcc, make, and cpp packages. You need to be able to compile C++ code. Need to figure which exact packages.

==Mac and Linux==
You already have a compiler, so download source code zip, unzip, and follow the tutorial on SU2’s site.

=Installation in Corn=

[https://web.stanford.edu/group/farmshare/cgi-bin/wiki/index.php/FarmVNC How to set up VNC for your computer]

Don’t bother attempting to move files around with Filezilla. Login to a VNC session and execute the <code>firefox</code> command in the terminal. Go to SU2's github repository and download everything there. Navigate to the zip file and
<code>unzip</code> the files. Navigate to the new path and execute these commands:

<code>
./configure --prefix="/afs/.ir/users/i/a/iangomez/SU2compiled/" CXXFLAGS="-03" --enable-mpi --with-cc=/usr/bin/mpicc --with-cxx=/usr/bin/mpicxx

make -j 8 install
</code>

'''Note''': change the prefix to your directory! If you’re confused by this read
<code>./configure --help </code> or email Ian or your RCC.

Once it’s compiled, you need to add the export commands they give you to your .bashrc file:

<code>
export SU2_RUN="/afs/.ir/users/i/a/iangomez/SU2compiled/bin"\\
export SU2_HOME="/afs/.ir/users/i/a/iangomez/SU2-master"

export PATH=$PATH:$SU2_RUN

export PYTHONPATH=$PYTHONPATH:$SU2_RUN
</code>

And obviously, change the paths to be correct. In order to find your .bashrc and open it in terminal:

<code>
cd

ls -al

vim .bashrc
</code>

Or you can open it in the GUI, by going to your home directory and pressing ctrl+h in order to show hidden files. Then double click your .bashrc file and add the specified lines. '''Make sure to execute the bash file to get the <code>PATH</code> updated: <code>exec bash</code>.'''

At this point, you will be able to run the code from any directory. However, if the files aren't executing, you can change their permissions to make them executables. Go to the directory where you’ve compiled SU2 and run the following command on each module, like this:<code> corn17:~/SU2compiled/bin> chmod +x SU2_CFD</code>

=Running sample code=
The tutorial is really great. Read it. But also make sure to grab the sample mesh files from the separate test case repository: [https://github.com/su2code/TestCases Link to SU2 Testcase meshes]
You will need it to run the config files that come pre-prepped for you.

[[Category: Rockets]]
[[Category:CFD]]

CFD Workflow

2016-03-30T21:01:10Z

Iangomez: created new category

Ian is currently working on creating a workflow for the Rockets team to get a better qualitative aerodynamic understanding of interesting geometries on rocket bodies.
Click through a particular piece of the workflow to get help with installation, running, and particular SSI use cases.

[[File:ONERA_M6.png | thumb | right | 330px | ONERA M6 wing in freestream flow with Ma ~ 0.8 visualized in Paraview]]

=The Big Picture=
There are are four pieces to a successful computation fluid dynamics simulation:

# '''Modeling''' - Solidworks
# '''Meshing''' - Pointwise
# '''Solving''' - SU2
# '''Visualization''' - Paraview

The most difficult part of the process so far has been finding a workflow in which all the pieces fit together. For instance, Pointwise is one of the few meshers that takes Solidworks files in directly. If no program could, we would have to go through many formats until we finally arrived at the one we wanted (which would be inconvenient, computationally and temporally expensive). SU2 outputs Paraview's native input format, which is great, since SU2 and Paraview are both open-source (and thankfully free).

== Special Thanks ==
Credit to the [https://solarcar.stanford.edu/ Stanford Solar Car Project] (SSCP) for giving us hints as to how they set up their own CFD workflow. Also big thanks to [http://adl.stanford.edu/people/jjalonso.html Juan Alonso] for helping us set up SU2 on Stanford's corn machine.

==[[Solidworks]]==
SSI's computer aided design program of choice since it is used in industry and is fairly easy to learn (and free for students). SSCP uses a lot of surfacing in order to get the complex geometries that they require. Most of our rockets will not require incredibly organic shapes (aside from a nose cone) so no need to get fancy. Any design (part, assembly, assembly of assemblies, etc) can be meshed with Pointwise. [http://www.solidworks.com/ Link to site].

==[[Pointwise]]==
Currently on their way to becoming a sponsor of SSI, Pointwise accepts Solidworks files and meshes them for you. Obviously, this part is extremely important in identifying the interesting geometries. (I haven't worked with Pointwise very much yet, so more on this to come). [http://www.pointwise.com/ Link to site].

==[[SU2]]==
Stanford developed, open source numerical flow solver. Written primarily in C++, the solver can easily extended due to its object-oriented programming and has fantastically written documentation. This will be SSI's solver of choice for the foreseeable future. [http://su2.stanford.edu/ Link to site].

==[http://www.paraview.org/ Paraview]==
Open source visualizer which is optimized for very large datasets. A complex but also well-documented tool which will be SSI's visualizer of choice.
[http://www.paraview.org/paraview-guide/ Link to user guide].

=Extra Resources=

[http://www.cfd-online.com/Links/onlinedocs.html CFD Online is awesome. Here is a link to their online doc resources]
[[Category:Rockets]]
[[Category:CFD]]

Category:CFD

2016-03-30T21:00:27Z

Iangomez: to keep things together

[[Category: Rockets]]

How to Run a SSI Workshop

2016-03-30T03:19:11Z

Iangomez: put in operations category??

#Determine topic/skill to be taught/improved
#Get approved by with Education and Outreach Coordinator
#Decide between series or one-time, preference towards one-time
#Establish Structure of Workshop
##Will people work in groups?
##Will you have a helper?
##Common structure for hands-on workshop:
###introduce topic
###introduce workshop goal
###quick “lesson” for about ¼ total workshop time
###Let people work for rest of time, be sure to guide them along and answer questions
##If there are safety concerns, address them - I will make sure they are.
#Establish Purpose and Audience Goals
##Are attendees coming to learn a fundamental skill, improve on a skill, explore an advanced topic, get hyped about something, etc…
#Check in with Education and Outreach Coordinator (4 and 5 combined = lesson plan)
#Estimate Attendance
##Recommended: send out interest email
###Optional: ask date/time that works for most (have options)
###If will have to buy items, make sure you do this step early enough so you know how much to get in step 8 (account for shipping time)
#Select materials and make a budget
#Check in with Education and Outreach Coordinator
#After approval, order materials
#Pick Location
##Will you need a special environment? etc…
#Reserve location
#Send out email with final date/time location.
##This should be done at least 3 days in advance
##optional: get headcount of who can make it
###(Likely to be less than those who say can make it)
#Prepare for hosting the workshop
##Recommended: Run over your plan with Education and Outreach Coordinator as if it were real at least a day before
#Host the workshop
#Let me know how it went
##Get feedback from people who attended the workshop

'''Try and get the media person to videotape if possible'''

[[Category: Operations]]

How to Run a SSI Workshop

2016-03-30T03:18:34Z

Iangomez:

How to Run a SSI Workshop

2016-03-30T03:17:37Z

Iangomez: derek wrote this!

#Determine topic/skill to be taught/improved
#Get approved by with Education and Outreach Coordinator
#Decide between series or one-time, preference towards one-time
#Establish Structure of Workshop
##Will people work in groups?
##Will you have a helper?
##Common structure for hands-on workshop:
###introduce topic
###introduce workshop goal
###quick “lesson” for about ¼ total workshop time
###Let people work for rest of time, be sure to guide them along and answer questions
##If there are safety concerns, address them - I will make sure they are.
#Establish Purpose and Audience Goals
##Are attendees coming to learn a fundamental skill, improve on a skill, explore an advanced topic, get hyped about something, etc…
#Check in with Education and Outreach Coordinator (4 and 5 combined = lesson plan)
#Estimate Attendance
##Recommended: send out interest email
###Optional: ask date/time that works for most (have options)
###If will have to buy items, make sure you do this step early enough so you know how much to get in step 8 (account for shipping time)
#Select materials and make a budget
#Check in with Education and Outreach Coordinator
#After approval, order materials
#Pick Location
##Will you need a special environment? etc…
#Reserve location
#Send out email with final date/time location.
##This should be done at least 3 days in advance
##optional: get headcount of who can make it
###(Likely to be less than those who say can make it)
#Prepare for hosting the workshop
##Recommended: Run over your plan with Education and Outreach Coordinator as if it were real at least a day before
#Host the workshop
#Let me know how it went
##Get feedback from people who attended the workshop
**Try and get the media person to videotape if possible

CFD Workflow

2016-03-29T20:50:12Z

Iangomez: added new header

Durand

2016-03-29T04:20:44Z

Iangomez:

{{problems}}

=[[Mission Control]]=

Durand 390 is SSI's headquarters.

=[[Durand 354 | 354]]=

=393=

What it is useful for, policy on use

=[[Durand 450 | 450]]=

Here is how to get to it, how to reserve it

=More useful links=

[link to durand address page Here is the associated Stanford Page.]
[link to campus map for durand Here is the associated campus-map.stanford.edu location.]

Durand

2016-03-29T04:15:12Z

Iangomez: added all the rooms

=[[Mission Control]]=

Durand 390 is SSI's headquarters.

=[[Durand 354 | 354]]=

=393=

What it is useful for, policy on use

=[[Durand 450 | 450]]=

Here is how to get to it, how to reserve it

=More useful links=

[link to durand address page Here is the associated Stanford Page.]
[link to campus map for durand Here is the associated campus-map.stanford.edu location.]

{{problems}}

Durand

2016-03-29T04:10:02Z

Iangomez: so people can find durand

hi

{{problems}}

Main Page

2016-03-29T04:08:58Z

Iangomez: added a how to join link

{{:Stanford Student Space Initiative (SSI)}}
Check out [[How to Join SSI]] for more information.

How to Join SSI

2016-03-29T03:48:31Z

Iangomez: added more info

Hello! There are a few things you need to do if you'd like to have full access to SSI's resources as a member.

=Becoming an official member=

# Fill out [http://goo.gl/forms/oNtfIehEpN this form] so we can add you to our official roster.
# Pay dues ($10) to one of our financial officers.
# In order to allow you access to our workspace, Mission Control, you need to do the following things:
##Go to AXESS and click "STARS" at the top
##Using either the "All Learning" list, or the Search Catalog, complete the following three safety trainings: '''EHS-4200: General Safety, Injury Prevention (IIPP), and Emergency Preparedness, EHS-1900: Chemical Safety for Laboratories, and EHS-2200: Compressed Gas Safety.'''
##Some time after completion, you will receive an email for each of these (can take up to 24 hours) certifying your completion. Save each e-mail as a PDF, or, less preferably, screenshot it. This PDF or screenshot '''must''' have your name on it.
##Create a folder on the [https://drive.google.com/folderview?id=0B7R_UB6uk1UAdWVLM1pURWxyMDA&usp=drive_web SSI Google Drive] with your full name, and, inside of it, upload PDF's or screenshots proving your completion of the safety trainings.

=Resources=

Here are some resources that will get you up to speed and on the same page with us:

==The Wiki==

The wiki is a great place to find guides, overviews, and generally useful documentation on SSI projects. Many of the most current plans and docs are in the drive though.

==[https://drive.google.com/open?id=0B5ethK6WQZfAWXgtR25KOEloN2M SSI Drive]==

The drive contains a lot of important documentation for each team. We are trying to put more emphasis on using the wiki as a place for longer-term knowledge storage.

== [https://ssi-teams.slack.com/ Slack] ==

Slack is the lifeblood of SSI. It is a messaging client that allows everyone within SSI to communicate. There are general channels (like #rockets), which allow us to push out general updates to everyone interested in the rockets team and direct messages in order to communicate with one person - although Slack has recently added a group messaging feature if you don’t want to make an entire channel for a 4 person chat - at a time. Notifications are pushed directly to your phone/computer/anything that has internet so that way we can infringe on all of your free time!

[https://ssi-teams.slack.com/signup ''Join the SSI Slack here.'']

== [[Mission Control]] ==

Mission Control can be considered the temple to SSI’s religion, the hub, nerve center, or kernel of all project activity. Located in Durand 390, Mission Control houses work sessions and project storage. Note: keycode access is required to the room. For specific questions, contact MC Hammer: Austin Pineault. Meetings or work sessions can also be conducted in the conference room, Durand 393 (often available), or Durand 450 (with prior reservation through AA Department Office on the second floor of Durand).

Rockets Team

2016-03-29T03:43:47Z

Iangomez: /* Mission Control */

{{rocket-sidebar}}

[[File: CardinalIILaunch.jpg | right| 250px | thumb | Cardinal II lifting off the pad on a J class motor.]]

The Rockets team is a student-led group striving to push the limits of high power rocketry. The team is currently working Project Daedalus, creating and testing novel systems for an eventual larger-scale rocket project. Project Daedalus. [[Project Daedalus]] is a suite of four rockets: [[Talos]] is a launch vehicle for [[Kythera]], [[Charybdis]] is testing out passive ascent stabilization with canted fins, [[Prometheus]] is demonstrating active roll control of a payload on descent, and [[Pegasus]] is testing a parafoil recovery system.

To accomplish each of the components of Daedalus, the Rockets team builds and launches [[L1 Certification|Level 1]], [[L2 Certification|Level 2]], and Level 3 [https://en.wikipedia.org/wiki/High-power_rocketry high-power rockets]. These are launched with national rocketry clubs.

The Rockets team Faculty Advisor is [[Dr. Hai Wang]]. The current team leads are Christopher May and Ian Gomez.

The rest of this page is dedicated to explaining everything an SSI Rockets Team member needs to know.

= Background =

== [http://wiki.stanfordssi.org/HPR_Background_Information High Power Rocketry]==

A high powered rocket is defined as a rocket that weighs more than 1500 grams and contains a motor or motors containing more than 125 grams of propellant and/or rated at more than 160 Newton-seconds of total impulse. There are different classifications for motors and different levels of certification required to use these motors. These rockets fall in the Class 2 Rocketry category as long as their total impulse remains below 41,000 Ns. Class 3 rockets require motors that cannot be bought commercially (and are classified as [[ITAR#Defense articles | ITAR defense articles]]).

{|
! Class
! Rating
! Total Impulse (N-s)
|-
|
Class 1 (Model Rocketry)

No certifications required
|-
|
| A
| 1.26-2.5
|-
|

| B
| 2.51-5.00
|-
|

| C
| 5.01-10.0
|-
|

| D
| 10.01-20.0
|-
|

| E
| 20.01-40.0
|-
|

| F
| 40.01-80.0
|-
|

| G
| 80.01-160
|-
|

Class 2 (High Power)

L1

|-
|
| H
| 160.01-320
|-
|

| I
| 320-640
|-
|

L2
|-
|
| J
| 640-1,280
|-
|

| K
| 1,280-2,560
|-
|

L3
|-
|
| L
| 2,560-5,120
|-
|

| M
| 5,120-10,200
|-
|

| N
| 10,200-20,500
|-
|

| O
| 20,500-41,000
|}

=== Level 1: H, I ===

There is no test required to acquire a Level 1 certification. Just a successful flight and recovery using an L1-class motor is required.

=== Level 2: J, K, L ===

The holder of an L1 certification (not necessarily from the organization they are attempting to obtain L2 certification from) must pass an examination on the subject of advanced rocketry concepts and have a successful flight and recovery using an L2-class motor.

=== Level 3: M, N, O and beyond ===

There are many requirements for an L3 flight. Check the NAR and TRA websites for further information.

==[[Project Daedalus]]==

Daedalus teaches the major design principles of high power rocketry with hands-on experience. Teams design and launch novel rocket concepts iteratively, starting with L1, L2 and finally ending with an L3 rocket that successfully flies the thoroughly tested design. The technology coming out of this project will benefit the Rockets Team’s flagship rocketry project.

Daedalus is the overarching rockets project for the 2015-2016 year that is divided into 4 subteams as described below.

=== [[Pegasus]] ===

The purpose of Pegasus is to demonstrate the feasibility of using a parafoil recovery system to create a controlled, directed recovery for a high-powered rocket from over 10,000 ft.

=== [[Prometheus]] ===

The purpose of Prometheus is to demonstrate roll control of a payload descent using PID-controlled fins.

=== [[Talos]]/[[Kythera]] ===

Talos is the launch vehicle for Kythera, SSI’s first generation flight computer system which will feature a Raspberry Pi that reads data from sensors and communicates that data to Teensys (Arduino-based microcontroller) in addition to using radios to provide real time GPS, orientation, and video data.

=== [[Charybdis]] ===

The purpose of Charybdis is to demonstrate passive ascent stabilization using canted fins.

= Expectations =

== Meetings ==

The Rockets Team has general meetings every week; during Spring Quarter of 2015-2016, these meetings are held on Thursdays from 8-9pm in Durand 450. They cover all relevant project updates (i.e. Daedalus team updates and launch logistics) and function as worksessions where all of the Rockets Team members are in the same place at once.

Each project under the Rockets Team umbrella needs to have at least one work session/meeting a week in conjunction with the team-wide meetings.

'''If you cannot make a project meeting, let your project lead know ahead of time.'''

== Previous Knowledge ==

We don’t expect you to know very much about rocketry. If you do, great! But if you don’t, we will spend the time teaching you the fundamentals and give you the opportunities and resources to learn as much about rocketry as you’d like. Working on a project is the best way to exercise and synthesize with the knowledge you gain from working with theory.

Rocketry is a multi-disciplined topic. Here’s a non-exhaustive list of useful disciplines:

<ul>
<li><blockquote>Heat Transfer</blockquote></li>
<li><blockquote>Thermodynamics</blockquote></li>
<li><blockquote>Fluid Mechanics (incompressible and compressible flow)</blockquote></li>
<li><blockquote>Physics</blockquote></li>
<li><blockquote>Material Sciences</blockquote></li>
<li><blockquote>Statics and Dynamics</blockquote></li>
<li><blockquote>Controls</blockquote></li>
<li><blockquote>Circuits</blockquote></li>
<li><blockquote>Amatuer Radio</blockquote></li>
<li><blockquote>Manufacturing</blockquote></li></ul>

Introductions to many of these are available on [[So You Want To...]]

== Time Commitment ==

Rocketry is difficult to master, but worth the tedious design process. The more time you put in, the better your project will turn out as well as experience less schedule slip. L1 and L2 do not require more than 10 hours combined (since they come from kits). L3 projects require much more time since these are designed from scratch and need to go through our NASA-inspired design process.

= The Process =

== Design Reviews ==

Note: For a much more specific documentation check out [https://docs.google.com/document/d/1c3D9EUYV-cxaDAc-bi3u-ufAYVxP0EIeB3hBln9TbUQ/edit# ''''The Process: From PDR to PLAR'''']. The document provides specific guidelines and expectations for each stage of the process.

As specified in NASA’s engineering design life cycle, multiple design reviews are used to assess the feasibility and practicality of both attempting and accomplishing a particular project. This includes a Preliminary Design Review ([https://docs.google.com/presentation/u/1/d/1DXe1mLi3W9Z8g58muUl7w96wpbG8cZbLAWL8znXPc2M/edit#slide=id.p3 ''PDR example'']) to assess mission goals, risks, and criteria and is followed by a Critical Design Review (CDR). By CDR, a project is expected to have assessed ''specific'' hardware and software configurations for viability, addressed questions raised in the PDR, and considered manufacturing and production of their final product. Both stages include extensive criticism and evaluation by other SSI members and external entities.

'''The PDR demonstrates that the overall preliminary design meets all requirements with acceptable risk and within the cost and schedule constraints.''' It shows that the correct design options have been selected, interfaces have been identified, and verification methods have been described. Full baseline cost and schedules, as well as all risk assessment, management systems, and metrics, are presented.

The CDR demonstrates that the maturity of the design is appropriate to support proceeding to full-scale fabrication, assembly, integration, and test and that the technical effort is on track to complete the flight and ground system development and mission operations in order to meet overall performance requirements within the identified cost and schedule constraints. Progress against management plans, budget, and schedule, as well as risk assessment, are presented. '''The CDR is a review of the final design of the launch vehicle and payload system'''. All analyses should be complete and some critical testing should be complete.

The FRR examines tests, demonstrations, analyses, and audits that determine the overall system (all projects working together) readiness for a safe and successful flight/launch and for subsequent flight operations of the as-built rocket and payload system. '''It ensures that all flight and ground hardware, software, personnel, and procedures are operationally ready.'''

Immediately prior to launch, SSI will conduct a Launch Readiness Review (LRR). The LRR is performed on-site to verify procedural compliance and compliance with applicable safety codes. Furthermore, please note that launch-site safety officers will also be present to approve and assess your rockets.

After launch, SSI will conduct a Post-Launch Assessment Review (PLAR). The PLAR is an assessment of system in-flight performance. The PLAR will determine if mission success criteria were met, discuss any adverse events, enumerate lessons learned, and describe any recommended changes to the SSI Rockets program.

== Budget ==

Rockets has [https://docs.google.com/spreadsheets/d/11LfZaV59FnFJyt4DnnCq2Vj7DgzM_2XfgwEPw27zTdI/edit#gid=0 ''a running budget''] in the Drive (Stanford Student Space Initiative > Teams > Rockets). Please add your purchases to the correct tab so we can have a running tally of what we’re spending.

== TRA and NAR ==

[http://www.tripoli.org/ ''Tripoli Rocketry Association (TRA)''] and [http://www.nar.org/ ''National Association of Rocketry (NAR)''] are the two major organizations that organize launches, certify members, and maintain specific standards that govern high power rocketry.

In order to launch high power rockets, you are required to be a member of either organization ([http://www.tripoli.org/Membership ''Tripoli Membership''] / [http://www.nar.org/join-nar/ ''NAR Membership''])

The closest Tripoli launch site to Stanford is [http://www.tccrockets.com/ ''Tripoli Central CA''] (near Fresno) and the closest NAR launch site is [http://www.lunar.org/ ''LUNAR''] (somewhat near Stockton). TCC holds HPR launches (max height 16,800’) on the 3rd Saturday of each month. LUNAR holds HPR launches (max height of 15,000’) on the 1st Saturday of each month in addition to low power launches (max height of 1000’) on the 3rd Saturday of each month at Moffett Field.

== Launches ==

Here is the launch procedure as lifted from the [https://docs.google.com/document/d/1ItllblKqc9oATIYz2Mf4VrZK0Fh1h3ohmwlDXR33KQM/edit ''Operating Principles and Risk Management''] document.

Once the team arrives at the launch site, the rules and regulations of the governing body sponsoring the launch will take precedence. Although procedure is likely to vary from site to site, the launch procedure usually occurs in this order:

<ol style="list-style-type: decimal;">
<li><blockquote>Those attempting to fly a rocket approach the Range Safety Officer (RSO) and officers in charge of the launch, sign in (with their member numbers) and usually pay a launch fee. If the flyer is attempting to get a certification, they will fill out relevant forms to declare their intention (these and other useful documentation pertaining to both national rocketry associations are included in the Appendix).</blockquote></li>
<li><blockquote>Depending on the skill level of the flyer, there are two variations of what may occur.</blockquote>
<ol style="list-style-type: lower-alpha;">
<li><blockquote>In the non-certification flight case, the RSO will inspect the rocket and send the flyer to set up the rocket on the launch pad. This requires placing the rocket on the launch rails, placing the igniter in the motor, and checking the launch pad electronics for errors before returning to a safe distance from the launch pad.</blockquote></li>
<li><blockquote>In the case of a certification, the RSO and someone above the flyer’s certification level will inspect the rocket and send the flyer (and another more experienced member) to set up the rocket for launch. The same setup process occurs as stated above.</blockquote></li></ol>
</li>
<li><blockquote>After the range has been cleared of spectators/flyers, the RSO announces each rocket and launches them one at a time (unless otherwise specified; an example of an exception is a drag race between two rockets).</blockquote></li>
<li><blockquote>Once the range is cleared of rockets, flyers recover their rockets.</blockquote></li>
<li><blockquote>If the flight is not a certification, the procedure ends here. Otherwise, the flyer shows his or her rocket to the RSO and has them sign off on the flyer’s paperwork if the flight is successful. The paperwork is then sent off to the headquarters of the organization and processed.</blockquote></li></ol>

== Rocket Naming Conventions ==

For mass certs:

SSI-R# will be the designation for general rocket launches (blanket certification launches).

Your rocket’s name can be whatever you would like it to be. Examples in the past are: ''Cardinal I'', ''Flamos'', ''Chris May'', etc.

For Daedalus:

SSI-[Level][three letter code denoting name][Launch number] ex. SSI-L3TAL1. These will not affect the number of SSI-R launches. They will have separate counts. The launch number will be useful if the same rocket goes flying again (which should be plausible if you don't mash it).

If the rocket is Class 3, no Level number is required.

== Rockets Leadership ==

The logistics required to run a fully operational Rockets team can be too much for just two co-leads to handle. The Rockets Leadership is a group of people who care about organizing the logistics behind launches and projects that the team is working on. If you show that you care and put in an exceptional amount of effort into your project, you can choose to be a part of this group.

[https://docs.google.com/a/stanford.edu/document/d/1-J5TS0MRgHi0HFTyPhYzzF6VZBa3dqO-WpxrCLgJIpQ/edit?usp=sharing ''Here is a document with all the roles on Rockets Leadership.'']

= Resources =

Other members are one of your best resources if you have any questions about rocketry. Other fantastic resources are laid out below.

== Rockets Drive ==

There are tons of useful things in the Rockets folder!!!!! Here are descriptions of a few of those folders.

=== [http://wiki.stanfordssi.org/Stanford_Student_Space_Initiative_(SSI) ''Wiki''] ===

Go here first for finding useful data on L1 certification procedures! You should add as much to the wiki as possible.

=== [https://drive.google.com/open?id=0B_uGMv8pu2KgVUFUcEpWRGt2M00 ''Archive''] ===

This holds all the older Rockets plans/documents/etc. Usually these documents are not particularly useful (which is why they are in the archive).

=== [https://drive.google.com/open?id=0B_uGMv8pu2KgU3Rsbi1KOFpuSzA ''Daedalus''] ===

This holds all the information for Daedalus, like team folders, L3 requirements, and PDRs & CDRs. Snoop around to see what they’ve done so far and steal information for your project (citing is always a good idea when you do take information).

=== [https://drive.google.com/open?id=0B_uGMv8pu2KgVkdjcGQtWTNsZU0 ''Getting Nerdy: Textbooks and Manuals''] ===

This folder holds a collection of useful texts ranging from textbooks, manuals, NASA articles and technical reports. If you need to learn things, [https://docs.google.com/a/stanford.edu/document/d/18PSjKqlVLTQzfJLG7ggiWY61W3ZcaD9kCcEePinAJw0/edit?usp=drive_web ''check out this document''].

=== [https://drive.google.com/open?id=0ByRlIAW5-8GqcUcyckNmZlFfN1U ''Launch Documentation''] ===

This holds all the launch documentation for upcoming launches and things like build slot signups, ride signups, rocket building instructions, required reading, pre-flight checklists, etc. Read through this folder and you’ll have a pretty damn good idea of launch logistics.

=== [https://drive.google.com/open?id=0B-5MRX1wVAAdNXQxUzdNVGNRRWc ''Rockets Operating Principles''] ===

This folder houses all of the operating principles, risk mitigation planning, and miscellaneous safety codes, documentation, and literally anything Stanford’s lawyers could possibly want from us. If you read the document you will have a very good understanding of how the team operates on an administrative level.

=== [https://drive.google.com/open?id=0B_uGMv8pu2KgdXo4YVJEV1duRlU ''The Design Process''] ===

This folder houses all you need to know to design, fabricate and launch a rocket from a documentation standpoint. Read it.

== [https://ssi-teams.slack.com/ ''Slack''] ==

Slack is the lifeblood of SSI. It is a messaging client that allows everyone within SSI to communicate. There are general channels (like #rockets), which allow us to push out general updates to everyone interested in the rockets team and direct messages in order to communicate with one person - although Slack has recently added a group messaging feature if you don’t want to make an entire channel for a 4 person chat - at a time. Notifications are pushed directly to your phone/computer/anything that has internet so that way we can infringe on all of your free time!

[https://ssi-teams.slack.com/signup ''Join the SSI Slack here.'']

== [[Mission Control]] ==

Mission Control can be considered the temple to SSI’s religion, the hub, nerve center, or kernel of all project activity. Located in Durand 390, Mission Control houses work sessions and project storage. Note: keycode access is required to the room. For specific questions, contact MC Hammer: Austin Pineault. Meetings or work sessions can also be conducted in the conference room, Durand 393 (often available), or Durand 450 (with prior reservation through AA Department Office on the second floor of Durand).

<noinclude>[[Category:Rockets]]</noinclude>

How to Join SSI

2016-03-29T03:37:11Z

Iangomez:

Hello! There are a few things you need to do if you'd like to have full access to SSI's resources as a member.

# Fill out [http://goo.gl/forms/oNtfIehEpN this form] so we can add you to our official roster.
# Pay dues ($10) to one of our financial officers.
# In order to allow you access to our workspace, Mission Control, you need to do the following things:
##Go to AXESS and click "STARS" at the top
##Using either the "All Learning" list, or the Search Catalog, complete the following three safety trainings: '''EHS-4200: General Safety, Injury Prevention (IIPP), and Emergency Preparedness, EHS-1900: Chemical Safety for Laboratories, and EHS-2200: Compressed Gas Safety.'''
##Some time after completion, you will receive an email for each of these (can take up to 24 hours) certifying your completion. Save each e-mail as a PDF, or, less preferably, screenshot it. This PDF or screenshot '''must''' have your name on it.
##Create a folder on the [https://drive.google.com/folderview?id=0B7R_UB6uk1UAdWVLM1pURWxyMDA&usp=drive_web SSI Google Drive] with your full name, and, inside of it, upload PDF's or screenshots proving your completion of the safety trainings.

How to Join SSI

2016-03-29T03:36:50Z

Iangomez:

Hello! There are a few things you need to do if you'd like to have full access to SSI's resources as a member.

# Fill out [http://goo.gl/forms/oNtfIehEpN this form] so we can add you to our official roster.
# Pay dues to one of our financial officers.
# In order to allow you access to our workspace, Mission Control, you need to do the following things:
##Go to AXESS and click "STARS" at the top
##Using either the "All Learning" list, or the Search Catalog, complete the following three safety trainings: '''EHS-4200: General Safety, Injury Prevention (IIPP), and Emergency Preparedness, EHS-1900: Chemical Safety for Laboratories, and EHS-2200: Compressed Gas Safety.'''
##Some time after completion, you will receive an email for each of these (can take up to 24 hours) certifying your completion. Save each e-mail as a PDF, or, less preferably, screenshot it. This PDF or screenshot '''must''' have your name on it.
##Create a folder on the [https://drive.google.com/folderview?id=0B7R_UB6uk1UAdWVLM1pURWxyMDA&usp=drive_web SSI Google Drive] with your full name, and, inside of it, upload PDF's or screenshots proving your completion of the safety trainings.

How to Join SSI

2016-03-28T23:36:58Z

Iangomez: added info

Hello! There are a few things you need to do if you'd like to have full access to SSI's resources as a member.

# Fill out [this form] so we can add you to our official roster.
# In order to allow you access to our workspace, Mission Control, you need to do the following things:
##Go to AXESS and click "STARS" at the top
##Using either the "All Learning" list, or the Search Catalog, complete the following three safety trainings: '''EHS-4200: General Safety, Injury Prevention (IIPP), and Emergency Preparedness, EHS-1900: Chemical Safety for Laboratories, and EHS-2200: Compressed Gas Safety.'''
##Some time after completion, you will receive an email for each of these (can take up to 24 hours) certifying your completion. Save each e-mail as a PDF, or, less preferably, screenshot it. This PDF or screenshot '''must''' have your name on it.
##Create a folder on the SSI Google Drive [here] with your full name, and, inside of it, upload PDF's or screenshots proving your completion of the safety trainings.

{{problems}}

How to Join SSI

2016-03-28T23:20:37Z

Iangomez: so we can point at this

hi

{{problems}}

Kythera

2016-03-28T07:02:41Z

Iangomez:

{{Problems}}

Cameron?

{{rocket-stub}}
[[Category: Rockets]]
[[Category: Avionics]]

Charybdis

2016-03-28T06:25:35Z

Iangomez: added pdr

{{rocket-project
| header = Charybdis (ARES-3)
| img link =
| launch details =

{{rocket-launch
|number=1
|launch class = L1
|launch date = February 6, 2016
|launch site = LUNAR
|next={{rocket-launch
|number=2
|launch class = L2
|launch date = Pending
|launch site = Pending
|next={{rocket-launch
|number=3
|launch class = L3
|launch date = Pending
|launch site = Pending
}}
}}
}}

| program = Project Daedalus
| last = Pegasus
| next = Prometheus
}}

= Team Summary =

Stanford SSI Rockets Team - Charybdis, 
Leland Stanford Junior University 
Stanford, CA 
Ian Gomez 
Project Manager 
iangomez@stanford.edu 
Calvin Lin 
Team Lead 
calvinlin@stanford.edu 
William Alvero Koski 
Structural Integration Analyst 
walverok@stanford.edu 
Navjot Singh 
De-spin Specialist and Senior Advisor 
navjot@stanford.edu 
Derek Phillips 
Avionics Specialist 
djp42@stanford.edu 

= Launch Vehicle Summary =

The Charybdis team under Project Daedalus is in the process of designing a spin-stabilized rocket to launch and reach an apogee of approximately 11,000 feet and dual deploy a main parachute and drogue parachute. The rocket will split between the aft airframe and forward airframe to release the drogue parachute and between the nose cone and forward airframe to release the main parachute. 
Charybdis will be launching an L1 test rocket on February 6, 2016 to test the effectiveness of canted fins in inducing a roll in the rocket and the subsequent de-spin prior to reaching apogee at a structurally small-scaled level. Then, the team will be be fulfilling similar objectives in spin-stabilization with the L2 rocket. The overarching goal of the rocket is to build an L3 rocket to test spin-stabilization and de-spin in a large-scaled rocket unit.

= Payload Summary =

The payload will include an avionics suite to support the dual deploy recovery system and the de-spin unit. The avionics suite will include core electrical components such as the Big Red Bee, Teensy 3.2, and custom altimeters provided by Stanford Student Space Initiative. Miscellaneous items of the payload include a GoPro Hero® and Adafruit with nine degrees of freedom.

= Vehicle Criteria =

== Mission Statement ==

The objective of Charybdis is to demonstrate spin stabilization and de-spin of a rocket using canted fins and a de-spin unit.

== Success Criteria ==

The mission will be considered successful if the rocket unit reaches spin stabilization, demonstrates successful de-spin prior to reaching apogee. The rocket must be recovered intact and reusable and pass the L3 certification inspection authorized by Tripoli.

== Constraints ==

# Tripoli height ceiling of 16,800ft
# Rocket construction to be made using a “minimum of metallic parts” excepting those necessary for airframe integrity
# Motor impulse to not exceed 10,240 Ns
# Redundant avionics, wiring, and safe arm systems
# Vertical descent speed of 20 ft/s maximum upon landing
# Budget of $4000
# Back up recovery system with a main parachute
# Redundant systems
# A landing within the radius of 300 feet of launching pad

= System Overview =

Immediately after the rocket is launched, the canted fins will begin to induce a spin in the rocket. At a moment before apogee, the SSI custom altimeter within the rocket will ignite Pyrodex powder (a black powder substitute) to trigger a cord cutter. The cord cutter will activate the de-spin unit to halt the rocket’s angular velocity. This gives a frame of time for the rocket to deploy the drogue parachute. After the rocket descends 5000 ft, the altimeter will cause the main parachute to deploy. 
The motor has dimensions of 98 mm in diameter and 548 mm in length. Given the rocket diameter, the motor will permit space for the canted fins to fit in the aft airframe.

== Propulsion System ==

The Cesaroni M1060-P was chosen because it is commercially available, reloadable, complies with the Tripoli and California restrictions, keeps our rocket sub Mach-1, and should achieve a maximum height under the height ceiling with the current mass estimates. 

=== Motor Performance ===

m0.3 m0.7 

[t]0.3

{|
|align="right"| Motor
| M1060-P
|-
|align="right"| Type
| Reloadable
|-
|align="right"| Diameter
|

|-
|align="right"| Length
|

|-
|align="right"| Avg. Thrust
|

|-
|align="right"| Max Thrust
|

|-
|align="right"| Total Impulse
|

|-
|align="right"| Burn Time
|

|-
|align="right"| ISP
|

|}

 

&

[t]0.7

M1060 Thrust curve (lbs. vs. s) [[File:M1060_thrust_curve.PNG|image]] 

=== Flight Characteristics ===

m0.3 m0.7 

[t]0.3

{|
|align="right"| Max Altitude
|

|-
|align="right"| Max Velocity
|

|-
|align="right"| Max velocity
|

|-
|align="right"| Max Acceleration
|

|-
|align="right"| Wet Mass
|

|-
|align="right"| Dry Mass
|

|-
|align="right"| Max Thrust
|

|-
|align="right"| Center of Gravity
|

|-
|align="right"| Center of Pressure
|

|-
|align="right"| Stability Margin
|

|-
|align="right"| Max Moment of Inertia
|

|-
|align="right"| Time to apogee
|

|-
|align="right"| Flight time
|

|-
|align="right"| Impact velocity
|

|}

 

&

[t]0.7

Vertical Velocity curve (ft/s vs. s) [[File:Vertical_velocity_curve.PNG|image]] 

Altitude curve (ft vs. s)

[[File:Altitude_curve.PNG|image]] 

Thrust curve (N vs. s)

[[File:Thrust_curve.PNG|image]] 

Mass curve (oz vs. s)

[[File:Mass_curve.PNG|image]]

Roll Rate Curve (rev/s vs. s)

[[File:Roll_rate_curve.PNG|image]]

= Structural System =

== Materials ==

The Charybdis rocket will have various materials, but primarily fiberglass for its resistance to high temperatures. The forward airframe will contain some polycarbonate for the window for the GoPro, but be primarily of fiberglass. The aft airframe, nosecone, and fins will also be fiberglass. The coupler linking the two airframes will be made from kraft phenolic and the bulkheads will be made from both aluminum and wood. The fiberglass was chosen for the body tube as the rocket will reach velocities of 0.92 mach and weaker materials may begin burning up.

== Nosecone ==

The chosen nosecone is the fiberglass nose cone from Public Missiles with a base diameter of 6.1 inches, length of 24 inches, and wall thickness of 0.125 inches. The shape of the fiberglass nose cone will be tangent ogive and have a capped end. Because the end of the nosecone is capped, deployment of the nosecone is much more convenient. The fiberglass material allows the nosecone to withstand up to . Furthermore, the shoulder has a diameter of 5.97 inches and a length of 5.5 inches.

== Fins ==

Three trapezoidal fins constructed from fiberglass with a square cross section and thickness of 0.12 inches will be included in the rocket. The root chord will be , a sweep length of , sweep angle of . Fiberglass is currently the best choice for our rocket because of ease of machining, cheapness, and amplifying stability of the rocket. Because the fins will not extend past the aft end of the rocket, there is no concern in fin damage during landing. After completing the flutter analysis, we can determine and finalize the effectiveness of our shape and dimensions. 

== Airframe ==

Both the aft and forward airframe will be long with an inner diameter of and wall thickness of . The airframes both weight . The materials of both airframes will be fiber glass. The aft and forward airframe will be attached with a PT-6.0 coupler from Public Missiles of length .

= Spin-Stabilization =

Spin-stabilization is the method of stabilizing a launch vehicle by means of spin. Spinning creates angular momentum, which induces resistance to deflecting forces such as wind. The Charybdis rocket will act on a two-axis stabilization.

== Canted Fins ==

To create spin, the three fins on the rocket will each be canted at . Any thing higher in magnitude will induce an incredible amount of spin. Any thing lower will not induce any spin. The fins will be inserted in cut slits at the aft end of the rocket.

== De-spin Unit ==

The de-spin unit will involve a yo-yo de-spin system. Two weights, each attached to a single string, are wound up around the outer side of the rocket. The two weights, each pre-calculated to have a certain mass, will be held within slots on the sides of the rockets. The two weights will be kept snug in the slots with a single string that passes through the airframe. A cordcutter, when charged with Pyrodex, will cut this intersecting string and release the weights. 
The reason the yo-yo de-spin was favored is because the unit does not require any calculations of initial angular velocity in order for the de-spin to halt the angular velocity. Rather, the only calculations required are the lengths of the two strings that wind around the airframe and the mass of the weights.

[[File:De_spin1.png|image]][[File:De_spin2.png|image]][[File:De_spin3.png|image]]

= Avionics and Telemetry =

In the forward airframe, the rocket will be split into the forward airframe avionics bay, herein referred to as the main avionics bay, and the aft airframe avionics bay, herin referred to as the secondary avionics bay. The main avionics bay will collect sensor information and communicate mission critical parts with the ground station. The unpressurized section is for the altimeter which will deploy the main parachute. The secondary avionics bay will contain an altimeter that controls the de-spin unit and drogue chute.

[[File:Block_Diagram.png|image]]

== Avionics Teensy Pinout and XBee Transmitter ==

In the main avionics bay, a Teensy 3.2 microcontroller will communicate with an XBee 9B 900 Mhz 250MW radio transmitter. The XBee will have a rubberduck RPSMA antenna and communicate information to the ground station in real time. There will be an Adafruit 9DoF sensor providing acceleration, velocity, and orientation information to the Teensy, which will store the data. Parts of the data, such as orientation, that are deemed mission critical will be transmitted through the XBee to the ground station. Everything described above will be connected to a single battery, an Anker Astro E1 5200mAh Portable usb battery pack and have an estimated maximum power consumption of 2 Watts.

== APRS Transmission ==

The second main component to the main avionics bay is a Big Red Bee connected to both an APRS transmit antenna and GPS receive antenna. The purpose of this component is to enable tracking of the rocket at the ground station. This component has its own power supply, and an estimated consumption of 1 Watt.

== Camera Payload ==

A GoPro Session® camera will be loaded directly below the main avionics bay in the forward airframe. The lens will be given a cut window slit on the forward airframe, and covered in polycarbonate in order to prevent any drag. The camera will be self-powered with its own battery, to save consumption from the polymer lithium ion cells.

== Altimeters ==

The two altimeters and their fuction are described in detail in the recovery section.

== Power Budget ==

The Anker Astro E1 Portable usb battery pack provides high energy density of , but is the heaviest component with a weight of . each. This battery will power the Teensy 3.2 and associated components: the XBee Pro 900 RPSMA and the 9 DoF Adafruit. The Big Red Bee and both altimeters are provided with their own power supplies. The total power consumption for the Teensy and associated components is approximately 2 watts. The Teensy uses 5.5V power draw, so the single Anker battery pack contains 28.6 Wh, which can power these components over r14 hours, which far exceeds the time frame of the launch and landing. In the unlikely even that the rocket goes off course, it will continue transmitting its location and other critical information to allow for proper recovery.

= Recovery =

The Charybdis rocket will employ a dual deploy recovery system, in which the drogue chute is released at apogee and the main parachute is released below apogee.

== Drogue Chute System ==

A Cert-3 L drogue chute from b2 Rocketry will be used to slow the rocket’s descent until the main chute can be deployed. It has a surface area of and a coefficient of drag of . With the parachute the rocket has a calculated descent rate of . The parachute weighs and has a packed size of long with a diameter.

== Main Chute System ==

A Cert-3 XXL main chute from b2 Rocketry will be used as the main chute for the rocket’s descent. It has a surface are of and a coefficient of drag of . With the parachute the rocket has a calculated descent rate of . The parachute weights and has a packed size of long and a diameter of . The main chute will deploy when the rocket is on the descent and is above the ground.

== Storage ==

The main parachute will be stored just behind the nosecone approximately from the front of the forward airframe. The drogue chute will be stored in the aft airframe just behind the coupler, approximately from the top of the aft airframe.

== Deployment ==

Both parachutes will be deployed when the airframes they are in respectively are pressurized by CO2 canisters in the coupler. As the parts separate, the shock cord pulls the rocket out for deployment. One possible idea for preventing tangling of the chute lines due to axial spin is having the hardpoint attachment for the shock cord be able to rotate, to allow the rocket and the chute to rotate independently. At apogee the rocket will be rotating at a speed of . This is before the de-spin unit is activated and is already slow enough that catastrophic failure should not be a problem.

== Guidance ==

The drogue chute will slow the rocket down moderately for the majority of the flight; however, it is not enough to ensure a smooth landing as the rocket needs to come down at a moderate speed so as to prevent the wind from blowing it too far away to retrieve. The main chute deploys at to slow the rocket down to a landing speed, but at a height that it should not be blown too far off course.

== Landing ==

The rocket will land at a speed of ; slow enough to ensure a safe landing so that recovery of the rocket in its entirety is possible.

= Manufacturing and Assembly =

For small-scaled testing, SSI’s Firestorm kit was used to build the L1 rocket. The only component of the kit not used was the fins. Included in the L1 is the de-spin unit, which includes a cordcutter, two weights, strings, an altimeter, and Pyrodex. The fiberglass fins will be hard cut from a chemical resistance fiber glass of in thickness. For L2 testing, the same process will occur. Any conclusions made from L1 testing will determine if any modifications in manufacturing or assembly will exist. 
For the final launch, structural parts will be purchased from trustworthy rocket parts vendors. The fins and airframes will be modified in the Mission control room.

= Risk Management =

== Safety Hazards ==

The largest concern of Charybdis is the de-spin unit. Because the weights of the yo-yo de-spin must unwind and be released, there is a possibility of inflicted danger. Not only will Charybdis have to perform tests, but also determine numerous methods in which the weights should descend. Some methods include placing mini parachutes on both weights or pack the weights with beads so that the beads separate when released and individually descend. For the L1 test, due to the miniscule mass of the weights (), dropping these weights without attaching a recovery system to them will prove sufficient to fall within a safety range. 
The next risk is the de-spin not completely halting the rocket’s spin. If the spin is still significant after the de-spin system is triggered, parachute lines of both the parachute and drogue chute will entangle when deployed. 
Another risk is the precessional rate of the rocket. As opposed to inducing rotational velocity, canted fins can also create precessional velocity. If the angle between the vertical of the precessional rate amplifies, it is possible that the rocket loses complete stability. In order to avoid high precessional rate, the fins must be analyzed not only with simulations but also mock launches and physical testing to predict success. 
Lastly, weather must be a precaution to determine whether or not Charybdis will launch. If windspeeds exceed on the ground or at , the launch must be postponed.

== Budget Risk ==

The total budget for Charybdis is $4000. Because Charybdis is comfortably under the budget ($2142), the only possible risk to our budget is the expenditures from multiple rounds of testing. Most parts can be reusable, but in case something breaks down, costs will rise.

= Activity Plan =

== Timeline ==

{|
| '''January 18, 2016'''
| Preliminary Design Review
|-
| '''February 3, 2016'''
| Complete L1 Charybdis Build
|-
| '''February 6, 2016'''
| L1 Charybdis Launch
|-
| '''February 9, 2016'''
| L2 De-spin Building
|-
| '''February 9, 2016'''
| L2 De-spin Test
|-
| '''February 20, 2016'''
| L2 Charybdis Launch
|-
| '''February 24, 2016'''
| Begin L3 Charybdis Assembly
|-
| '''March 1, 2016'''
| L3 De-spin Testing
|-
| '''March 3, 2016'''
| L3 Building Completion
|-
| '''March 5, 2016'''
| Critical Design Review
|-
| '''March 19, 2016'''
| L3 Charybdis Launch
|}

[[Category: Daedalus]]
[[Category: Rockets]]