Australian researchers have programmed a satellite computer operating 800km above the Earth to repair itself from blasts of potentially catastrophic space radiation such as those emitted by a sun spot last week.
A team at the Canberra-based Co-operative Research Centre for Satellite Systems (CRCSS) used a combination of software and components called Field Programmable Gate Arrays (integrated circuits that can easily be programmed while in use) to create their self-healing computer on the satellite FedSat.
They were able to test the device in May when the satellite recorded a bombardment of fast-moving charged atomic particles from the Van Allen radiation belt, a zone of intense particle radiation 1,930km above the Earth.
Programme leader Dr. Anwar Dawood said such radiation could cause a variety of errors on on-board systems and increase the risk of losing control of a satellite.’Our computer can automatically detect this kind of damage and reconfigure its own circuits to re-establish proper operations. During a period of high-radiation activity we were able to demonstrate for the first time that this technique works,’ he said.
Indeed, the centre’s new high-performance computing experiment not only automatically detected a fault but also analysed the problem and restored itself to full capability – all without human intervention.
‘We can also send new instructions to the computer, meaning that the system is flexible enough to be able to adapt for new tasks,’ said Dawood.
Another experiment on FedSat is an on-board magnetometer measuring space weather such as charged particles pouring from the sun and magnetic storms, as occurred in May and last week.
‘This is the environment in which modern communications and energy systems both in space and on Earth must operate reliably, and we are gathering important new data to help us understand how to design disruption-proof equipment,’ said the centre’s chief executive Dr. Andrew Parfitt.
A third experiment involves using FedSat’s GPS system to check the electron content of the Earth’s upper atmosphere. According to Parfitt, FedSat is the first small satellite to operate in the frequency range for Ka band satellites (communications satellites providing services to and from small earth stations).