Paper Details

Communicating Process Architectures (CPA)
 Title: CSP In Orbit - a Recent Satellite Application
 Conference: Communicating Process Architectures 2014
 Authors: Roger Peel, Barry Cook, Paul Walker
4Links Ltd.
 Abstract: We have used the philosophy of CSP to guide the design of a successful range of products for the Space industry. All revolve around a development of the Transputer communication link – SpaceWire – based on the T9000 link with changes (not all are improvements) to suit this sector. SpaceWire is used increasingly, worldwide (UK, USA, EU, Japan, Russia, etc.), for on-board data communications in a wide range of satellites.  [The Transputer has been used in successful missions - some still functioning – and is even being designed into new spacecraft!]

Spacecraft are hard to repair after launch and on-board systems contain multiple, redundant, copies of important units with a switch-over algorithm to ensure continued operation. Network, rather than traditional bus, topologies allow Fault Detection, Isolation and Recovery (FDIR) algorithms considerably more freedom and are subject to ongoing research. We are currently part of a project funded by the European Space Agency (ESA) and led by Astrium (now Airbus) delivering a system of units, each of which provides a hardware simulation of an on-board unit. Astrium/Airbus will implement a proposed FDIR algorithm that will be run in real-time with faults introduced and the resulting behaviour observed and checked.

Although we are only now delivering first units to Astrium/Airbus, we took a small system to the Farnborough International Airshow with a very simplified FDIR algorithm and were able to show correct recovery from deliberately introduced failures. We will demonstrate the system in operation – an example of a real, industrial, application of CSP.  

BibTeX Entry