FDIR Architectures for Autonomous Spacecraft: Specification and Assessment with Event-B

On-board Fault Detection, Isolation and Recovery (FDIR) systems are considered to ensure the safety and to increase the autonomy of spacecrafts. They shall be carefully designed and validated. Their implementation involves a relevant knowledge of items like functions and architectures of the system, and a fault model in relation with these items. Thus, the event-B method is well suited to correctly specify and validate on-board safety architectures. This paper focuses on the FDIR concept presentation and the use of event-B for formalising and for refining the FDIR concept.