Since April, I have been working with Sam Flynn (https://drook.dev) to make this balloon payload, UpLink. We did a similar launch last year with Hack Club but this was our first independent launch.

UpLink was a 491 gram payload testing the insulation properties of 3D printing filaments, while also transmitting 320x240 images over a radio link -- up from the 18x10 images last year!

This is a writeup on our engineering process, mistakes made, and learning experiences. It covers:

- Custom electronics designed in KiCad

- Firmware design

- Results from the data we received on the ground

- Image transmission

- Launch day logistics, and where things went wrong

All hardware, software, firmware, and CAD is available on GitHub: https://github.com/radeeyate/UpLink, licensed + certified as open source hardware: https://certification.oshwa.org/us002826.html

If you just want to see the images received, I put up a gallery here: https://uplink.gallery.radi8.dev/

If you have any questions, comments, or concerns, let me know. I'm happy to answer anything!

Fun writeup! I was surprised by the part about styrofoam boxes though:

  Despite their popularity, they have a few disadvantages:

  They come in predefined sizes which mandate a certain weight allowance
  They cannot be flexible for your specific payload, making it hard to be efficient with payload layout
  They are expensive compared to more custom solutions

Buying a styrofoam box and just accepting that it's gotta be that shape and size feels like a huge waste.

Wait, so at 28k/km the temp goes up to 15C?

This is all very cool but this temperature reading caught my eye as unexpected.

Impressive level of detail, impressive work for anyone, much less high school students.

The images seem a bit scrambled, presumably due to missing data blocks. At that low a resolution, have you considered maybe Robot36 SSTV?