Changes

no edit summary
Line 1: Line 1: −
{{TechSidebar
+
{{HABEES-sidebar
 
| header = Oscar
 
| header = Oscar
 
| img link = File:oscar.JPG
 
| img link = File:oscar.JPG
Line 5: Line 5:  
| techline = Balloons Core Avionics
 
| techline = Balloons Core Avionics
 
| version = Generation I
 
| version = Generation I
| name = Oscar
+
| name = Oscar (the grouch)
| missions = SSI-39, SSI-40
   
}}
 
}}
      
The '''Balloons Gen 1 Avionics Platform''' is the first core avionics suite developed by HABEES. Named ''Oscar'', this avionics suite flew on a failed technology demonstration in SSI-39, followed by a successful demonstration in SSI-40. As the first core avionics suite, it set the expectations for features to be included in subsequent revisions.  
 
The '''Balloons Gen 1 Avionics Platform''' is the first core avionics suite developed by HABEES. Named ''Oscar'', this avionics suite flew on a failed technology demonstration in SSI-39, followed by a successful demonstration in SSI-40. As the first core avionics suite, it set the expectations for features to be included in subsequent revisions.  
Line 52: Line 50:     
=== Top Sheet ===
 
=== Top Sheet ===
 +
[[File:oscar_raw.JPG | right| thumb | <center> Oscar PCB </center>]]
 
The top sheet displays the overarching hierarchy of the avionics board. Only perimeter Teensy pins were utilized, hence pins 24-33 and A10-A14 are NC. The GPS was connected to Hardware Serial 1 over pins 0/1. Pin 2 was driven low when SD card was detected (output of the Micro SD sheet). Pins 3-5 were not utilized. Pins 6-9 were used for RockBlock operation, although NETAV & SLEEP were not used for actual operation, and may be discarded in the future. Pins 10-13 were used to define the SPI Bus, and pin 10 was used as the Micro SD chip select. As seen in the bottom left, pinouts were supplied for I2C and SPI. VIN was supplied with +5V from the boost circuit. Two decoupling caps for +3.3 and +5 were sourced local to the MCU. Pins 22-20 were defined as chip selects for the thermocouple and BMP 280's (22 for thermocouple, 21/20 for BMP280). Pins 19/18 defined the I2C bus. The I2C bus had five total devices: Two MS5803's, One MPL3115A2, One MCP23017 multiplexer, and one RTC IC. Pin 16 connected to the battery protector (LTC4218) power good indicator. Pins 15 and 14 were used for current monitor (via 4218) and battery voltage detection.  
 
The top sheet displays the overarching hierarchy of the avionics board. Only perimeter Teensy pins were utilized, hence pins 24-33 and A10-A14 are NC. The GPS was connected to Hardware Serial 1 over pins 0/1. Pin 2 was driven low when SD card was detected (output of the Micro SD sheet). Pins 3-5 were not utilized. Pins 6-9 were used for RockBlock operation, although NETAV & SLEEP were not used for actual operation, and may be discarded in the future. Pins 10-13 were used to define the SPI Bus, and pin 10 was used as the Micro SD chip select. As seen in the bottom left, pinouts were supplied for I2C and SPI. VIN was supplied with +5V from the boost circuit. Two decoupling caps for +3.3 and +5 were sourced local to the MCU. Pins 22-20 were defined as chip selects for the thermocouple and BMP 280's (22 for thermocouple, 21/20 for BMP280). Pins 19/18 defined the I2C bus. The I2C bus had five total devices: Two MS5803's, One MPL3115A2, One MCP23017 multiplexer, and one RTC IC. Pin 16 connected to the battery protector (LTC4218) power good indicator. Pins 15 and 14 were used for current monitor (via 4218) and battery voltage detection.  
   Line 62: Line 61:  
=== RTC ===
 
=== RTC ===
 
A DS1307 RTC IC is utilized for the real-time clock. The Teensy 3.2 internal RTC is avoided due to past difficulties/problems. The DS1307 is powered by 5V (no 3.3V variety exists). A 32.768kHz 12.5pF time-keeping crystal X1 is used for the RTC, and a keystone 12mm coin cell holder provides backup power for the RTC. A 100 nF decoupling cap is provided.
 
A DS1307 RTC IC is utilized for the real-time clock. The Teensy 3.2 internal RTC is avoided due to past difficulties/problems. The DS1307 is powered by 5V (no 3.3V variety exists). A 32.768kHz 12.5pF time-keeping crystal X1 is used for the RTC, and a keystone 12mm coin cell holder provides backup power for the RTC. A 100 nF decoupling cap is provided.
 
+
[[File:oscar_full.JPG | right| thumb | <center> Oscar in SSI-39, along with the RockBlock, Battery Pack, and Heater </center>]]
 
=== RockBlock ===
 
=== RockBlock ===
 
The RockBlock uses a 2x3 vertical Molex microfit connector. It is provided +5V, GND, Serial TX/RX lines, as well as connections for the SLEEP & NETAV pins, which are not utilized.
 
The RockBlock uses a 2x3 vertical Molex microfit connector. It is provided +5V, GND, Serial TX/RX lines, as well as connections for the SLEEP & NETAV pins, which are not utilized.
Line 134: Line 133:     
=== SSI-39 ===
 
=== SSI-39 ===
 +
[[File:ssi40oscar.jpg | right| thumb | <center> Oscar, during SSI-40 </center>]]
 
SSI-39, the inaugural flight of Oscar, was a flight plagued with unfortunate mistakes, and some poor decision making. Flight software for Oscar was completed approximately 4 hours before departure from campus, fully functional. En route to launch site, additional components were added, including ascent rate calculation,  as well as GPS flight mode and a few other features.
 
SSI-39, the inaugural flight of Oscar, was a flight plagued with unfortunate mistakes, and some poor decision making. Flight software for Oscar was completed approximately 4 hours before departure from campus, fully functional. En route to launch site, additional components were added, including ascent rate calculation,  as well as GPS flight mode and a few other features.
   Line 143: Line 143:     
=== SSI-40 ===
 
=== SSI-40 ===
[[File:ssi40oscar.jpg | right| thumb | <center> Oscar, during SSI-40 </center>]]
   
SSI-40, taking place shortly after SSI-39, was an exact re-flight of Oscar, with the modification of having the GPS antenna taped to a habhive wall. The system performed nominally from prep to launch and throughout the entire flight. Communications were frequent, coming in often 30 seconds apart. The payload successfully recorded and transmitted flight critical parameters for the entire duration of the flight, including internal and external temperatures, altitude, ascent rate, power state, and more. A successful cutdown was also triggered at 25 km using a custom FET and nichrome wire. A heater was included but did not activate during the flight.  
 
SSI-40, taking place shortly after SSI-39, was an exact re-flight of Oscar, with the modification of having the GPS antenna taped to a habhive wall. The system performed nominally from prep to launch and throughout the entire flight. Communications were frequent, coming in often 30 seconds apart. The payload successfully recorded and transmitted flight critical parameters for the entire duration of the flight, including internal and external temperatures, altitude, ascent rate, power state, and more. A successful cutdown was also triggered at 25 km using a custom FET and nichrome wire. A heater was included but did not activate during the flight.  
    
The payload was recovered floating atop algae in an irrigation canal. All flight electronics remained in nominal state at time of recovery. The Micro SD card contained thorough data from throughout the entire flight.
 
The payload was recovered floating atop algae in an irrigation canal. All flight electronics remained in nominal state at time of recovery. The Micro SD card contained thorough data from throughout the entire flight.
 +
 +
[[Category: High Altitude Balloons]][[Category: HABEES]]