Category:Satellites

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Revision as of 22:52, 14 September 2023 by Theo24 (talk | contribs) (→‎Sapling Giganteum: 2022–2023: Continued to update Sapling-2 description)
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SatsLandingPage.jpg
Sapling Sempervirens (Sapling-1) at The Dish

Welcome to the SSI Satellites Team! Whether you're an incoming frosh, tired old senior, graduate student, alumni, or even not a part of the Stanford community, we're glad you're here. Our current mission is SAMWISE, a CubeSat with a number of technological advancements compared to our prior missions. Our Satellite Team Leads are

SlackLogo.png@Spencer Wallace  and SlackLogo.png@Ashley Raigosa  and SlackLogo.png@Theo Makler 

Getting Started with Satellites

Stanford Affiliated 🌲

If you're a Stanford student, professor, or affiliate we'd love for you to join the Satellites community! For information on joining SSI as a whole, check out the How to Join SSI page.

Once you've joined our Slack messaging hub, you'll be able to join all of our Satellites-specific channels! Definitely join the general satellites channel which is where we'll post all of our major updates and make big announcements. We've also got a lot of subteams, each with their own channel (we love our Slack channels here at SSI). Check out the Subteams section on this page to learn about them and join any channels you find interesting.

And of course if any questions or confusions come up, don't hesitate to reach out to any of the Satellite Team Leads. Also feel free to reach out to Subteam Leads if you have subteam-specific questions!

Outside Stanford ❄️

If you're not affiliated with Stanford but are interested in the team and our projects, we'd still love to have you! To get in touch, please email one or all of the team leads Ashley Raigosa, Spencer Wallace, and Theo Makler.

Onboarding Events Calendar

Check out the SSI Updated General Event Calendar to stay up-to-date on all of our onboarding events! This is still a work-in-progress so stay tuned for more information :)

Our Website: saplingsat.org

One of our main goals of the satellites team is to increase accessibility to space, and while we can have made a ton of progress on this from an engineering standpoint, it's pretty limited unless we get the word out. So we made a website! At saplingsat.org, you'll be able to find everything from our project overview to how to assemble our main flight computer. If you wanna take a deep dive into our software repositories or just brush up on terminology, the website is the place for you :)

Current Mission: SAMWISE

Our current mission is SAMWISE, a 2U CubeSat (10cm x 10cm x 20cm rectangle) with a bunch of super cool technologies. Stay tuned.

Subteams

Building a satellite is definitely not a simple task! There's a lot that goes into each one, so to help streamline things we divide up into subteams. Each of these subteams has a specific task associated with the satellite, and together they work together to make the mission a success! Below you'll find descriptions of each subteam, ways to contact our current subteam leads, and links to their respective Slack channels.

Attitude Determination and Control (ADCS)

Slack Channel: satellites-adcs Subteam Lead: Grant Regen

Here's the description

Avionics

Slack channel: satellites-avionics Subteam Lead: Hunter Liu

Here's the description

Payload

Slack channel: satellites-payload Subteam Lead: Niklas Vainio

Welcome to the payload subteam! The payload often defines the mission of the satellite, so it's basically the most important part :) These payloads can be anything from telescopes like Hubble to communication systems like Starlink. Our recent satellites have largely focused on low-cost camera systems and radio modules. This subteam covers a huge variety of topics, so no matter your interests definitely join the Slack and reach out!

Our current projects are developing a multi-camera system and a higher speed radio module for the SAMWISE mission. This system is based on the Raspberry Pi architecture and will include an Earth-facing camera, a star tracker used in conjunction with our ADCS system, and a selfie camera! The higher speed radio will allow us to more quickly send images back down to Earth.

In our Sapling missions, the payloads consisted of a Google Coral Dev Board Mini computer and a Google Coral Camera. These payloads were selected to demonstrate on-orbit image processing and selection using an AI filter. This process would allow the Google Coral to select a single "best" image out of a series of images taken, reducing the amount of data needed to be transmitted down to Earth.

Software

Slack channel: satellites-software Subteam Lead: Kien Deshpande

Here's the description

Structures

Slack channel: satellites-structures Subteam Leads: Jacob Mukobi, Siolé Mayeski, and Jeremy Merritt

Here's the description

Systems

Slack channel: satellites-systems Subteam Lead: kinda everyone!

Here's the description

Past Missions

Sapling Giganteum: 2022–2023

Sapling Giganteum

Also referred to as Sapling-2, this was the second of the Sapling series of 1U CubeSats. This mission represented a major step forward in our satellite design and became the first SSI satellite to successfully make contact with the ground once deployed.

Sapling-2 launched on SpaceX's Transporter 7 at 11:48pm on April 14th, 2023 from Vandenburg Space Force Base in Southern California. Shortly after deployment contact was made with SSI's Durand ground station.

In addition to incremental but critical improvements to the internal electronics of the satellite, Sapling-2 featured a number of major changes from the design of Sapling-1. The first iteration of the (name for the sheet metal structure) debuted on this satellite. This structure, made of off-the-shelf aluminum cut with a CNC and bent into precise shape before being anodized, lowered material costs and allowed for rapid prototyping. An evolution of this structure is being created for the SAMWISE satellite and will underpin all missions in the near future.

Sapling-2 also showcased an advanced attitude determination and control system (ADCS) featuring magnetorquer coils positioned on each of the six faces of the satellite. When activated, the magnetic field created by these coils interacts with the Earth's magnetic field and generates a torque on the satellite, allowing for rotation around all three axes. This could be used to de-tumble the satellite after deployment and for pointing of the Google Coral camera.

On June 18th, 2023, Sapling-2 stopped sending telemetry. While the precise cause is unknown, it is likely that a solar storm which occurred around that time disabled the satellite. Prior to its shutdown the satellite was in good health, with a high state of charge and in a nominal temperature range.

Sapling Sempervirens: 2020–2023

Sapling Sempervirens before delivery

Also referred to as Sapling-1, this was the first of the Sapling 1U cubesats (better descriptions to come + photos!)

Sequoia: 2019–2020

Sequoia was a planned 3U CubeSat that would demonstrate on-board image classification and processing with updateable machine learning models. The goal of the project was to obtain a high volume of scientifically important imagery for ecological and climatology research. Researchers many times have no need of images saturated with clouds or uninteresting areas—so why not filter them out with a convolutional neural network? We will retrain Sequoia’s deep learning with images taken by the satellite, uplinking improvements. SSI worked on developing deep learning models for forest fire risk assessment and detection and a number of other applications. The mission architecture is user definable with the operator specifying desirable image locations or types and resolutions, and the satellite maximizing delivery of fully open-source images.

Project materials can be found in the Sequoia GitHub.

POINTR: [year]–2018

The Satellites Team developed various Optical Communications technologies, culminating in the launch of POINTR. This was a 1U segment of a 3U CubeSat launched in 2018, but it unfortunately never connected with ground control due to improper orbital insertion from the launch provider.

Additional Projects

In addition to projects taken on by the team as a whole, satellites members have worked in Stanford faculty labs to build:

  • SNAPS, the Stanford NAno Picture Satellite, a 1/4U imaging CubeSat deployed from the ISS in 2016
  • QB50 Discovery, Stanford's submission to an international 50-member CubeSat constellation
  • Morgana, a CubeSat designed to study high energy particles in the upper atmosphere. (Cancelled)

Photos

If you've got a Stanford login you can take a look at our photos! The satellites photos can be found here.

Old Documentation

This team has been around for a long time! There's a lot of sub-pages on this wiki that are now redundant because of our website or are simply outdated. Until I figure out what to do with them I'll keep all the links in this section so we don't loose anything – Theo :)

Attitude Determination and Control (ADCS)

Sequoia GNC

Satellite Avionics

Satellite Software

Satellite Structures