On Saturday 14th December 2002, a Japanese H-2A booster launched FedSat,
Australia's first satellite for 30 years - and the first foreign payload
launched with the H-2A.
Video and Stills of launch and payload separation are at
Article about the software and hardware on board
Rogue's Gallery of the engineering team
This microsatellite is possibly the densest in terms of payloads-
per-cubic metre and payloads-per-kilo that has yet been orbitted.
NewMag Magnetometer, GPS Ionospheric probe, Field Programmable
Gate Array experiment, and the Communications payload with 2
different experimental comms systems and an experimental processor,
plus a star camera. All from different organisations, with
different computers, some big-endian, some little-endian, some
with 1750A floating-point format, some with IEEE, and using different
languages. In a cube that's about 1/2metre on a side, massing just
58 kg. All up cost less than $200,000 US ($400,000 Aus) per Kg.
The on-board computer that is "one ring to rule them all" - an
ERC-32 running at a glacial 8 MHz, with 16 MB of normal RAM.
This has to communicate with all the payloads, store their data
in mass memory, plus monitor hundreds of different voltages,
temperatures, comms statusses, reprogram the payload computers
as required, start and stop experimental campaigns out of ground
contact, and relay many Megabytes of telemetry in the 15-20 mins per
day its in contact. Oh yes, it can be reprogrammed from the ground
too while in flight.
It's the first satellite we've built in 30 years, so was built
by a team still "learning on the job" with no outside help.
The language on the On Board Computer? Ada-95. Of course.
The compiler? Gnat 3.13p
*That* is why we got contact in the first ground pass - not
just contact, but (3,25) housekeeping parameter report
messages, even during tumbling and periodic blackouts.
And were able to activate the ACS (Attitude Control
System) nominally at first attempt.
"In Space, no-one can press CTRL-ALT-DEL"
But with Ada, you don't have to.
Alan Brain (Head of FedSat On-Board Computer Software Development)
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