In the vacuum chamber, no one can hear you scream

PicSat is back in the thermal vacuum chamber SimEnOm! After having cycled the payload electronic board v1.00, the payload electronic board v1.10, and the full engineering model, we are now cycling the flight model of PicSat! We have just removed the telescope so that our very talented optical team can continue working on the alignment. But there is no star in SimEnOm anyway, so that’s fine.

We are cycling the satellite from -20°C to +30°C. These are not extreme temperatures, but they are representative of the range we expect to have in space.

Installing PicSat in the chamber took quite a bit a time, as we had to be extremely careful not to damage anything, or deploy the solar panels by mistake. Oh, and yeah, we somehow found a way to forgot to put the latest version of the code on the payload board when integrating it into the satellite, so we also had to unscrew one side of the satellite to plug in the JTAG connector and (unsuccessfully) try to update it…

(management banned the picture here)

Uh? But wait a minute, haven’t we developed, wrote and tested a bootloader for this board, allowing updates to be performed remotely by radio? Yeah, but we kinda messed up with the versions here too…

ANYWAY, the main computer receives and replies to all our TCs (aka telecommands) smoothly; it tirelessly emits its beacon every 10 s; and we see all those sweet TM (telemetry) packets with our constantly changing, ever-evolving ground segment software! Plus, the faulty payload bootloader still accept/reply to some commands, so evreything is fine. There is even a beacon on the old payload app! So, really, what more could we ask for? Better version control / software quality management, maybe? Meh! Who needs that?

The main objective was to check the full communication chain at different temperatures, and thus the test campaign was unanimously considered a SUCCESS.

Next: vibrations!

Sylvestre is installing PicSat into the testPOD. Worry not: he was very well supervized during this operation.


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