APIC Safety Lead for the GRACE mission and the LSP Range Safety required AMSAT Engineering to demonstrate the safety of the Sanyo KR-1400AE cells used in the Fox-1A satellite, in light of the cells having no UL listing nor available manufacturer documentation on the cell case pressure and venting pressure.
After a few weeks spent on planning, obtaining components, construction, and rehearsal (there are no “do-overs” once the circuit is closed!) a small team consisting of Bob Fitzpatrick KB5SQG, Shura Buxton KD5FCQ, and Jerry Buxton NØJY performed the test on Sunday afternoon, December 7, 2014. The cell was subjected to a direct short circuit and the current, temperature, and physical behavior were observed, logged, and captured on video. While the report to APIC is For Official Use Only, the video is not and so you are invited to view the raw footage (minus a couple of spots where audio has been muted for expletives or chatter unrelated to the test) on YouTube.
The test was successful, as it was demonstrated that the cell did not burst nor greatly deform, there was no fire or damage, and no liquid leakage. There was quite a surprise, though!
The multimeter is reading mV DC across a .001 ohm current sense resistor, so the reading you see directly corresponds to current. Temperature is in degrees Celsius.
And Murphy was of course present, as a natural part of anything involving amateur radio activities. Fortunately, the stopwatch wound up almost exactly 10 seconds behind so translation of the readings was pretty simple!
At the 2014 AMSAT Space Symposium AMSAT Vice President – Engineering Jerry Buxton announced the plan for the next generation of AMSAT satellites. “The door is open for everyone, to submit their ideas. AMSAT Engineering has a long term strategy and this is the first step.”
The Engineering long term strategy includes the following goals
Advancement of amateur radio satellite technical and communications skills
Enhance international goodwill
Grow and sustain a skilled pool of amateur radio satellite engineers
Establish and maintain partnerships with educational institutions
Develop a means to use hardware common to all opportunities
With respect to the last goal Jerry said “Within the bounds of the type of satellite it takes to achieve any of the various orbit opportunities, let’s consider in those plans the possibility of developing a platform that can suit any and all orbits. Perhaps a modular CubeSat, using a common bus as we did in Fox-1, which gives great flexibility in building and flying different sizes and configurations of CubeSats with simple common-design hardware changes.”
Submissions should be thorough and contain the following information. The purpose of the proposal is not just in suggesting an idea; being an all-volunteer team AMSAT needs your help in carrying out the idea.
Implementation – CubeSat platform
Cost – volunteer resources, commercial (COTS) units
Launch – how does it get to orbit
Strategy – how it fits into AMSAT’s Engineering long term strategy
As mentioned above the idea should be based on the CubeSat platform. This is the standard through which we will look for launches in the foreseeable future.
The Fox-1A Engineering Unit transponder was on the air at 2014 Space Symposium. Attendees were able to work each other through the transponder and pose for pictures while holding the actual engineering unit. In addition, the slow speed telemetry that accompanies every voice ID beacon and transponder conversation was being received, decoded, and displayed for all to see.