Applying Active Diagnosis to Space Systems by On-Board Control Procedures

International audienceThe instrumentation of real systems is often designed for control purposes and control inputs are designed to achieve nominal control objectives. Hence, the available measurements may not be sufficient to isolate faults with certainty and diagnoses are ambiguous. Active diagnosis formulates a planning problem to generate a sequence of actions that, applied to the system, enforce diagnosability and allow to iteratively refine ambiguous diagnoses. This paper analyses the requirements for applying active diagnosis to space systems and proposes ActHyDiag as an effective framework to solve this problem. It presents the results of applying ActHyDiag to a real space case study and of implementing the generated plans in the form of On-Board Control Procedures. The case study is a redundant Spacewire Network where up to 6 instruments, monitored and controlled by the on-board software hosted in the Satellite Management Unit, are transferring science data to a mass memory unit through Spacewire routers. Experiments have been conducted on a real physical benchmark developed by Thales Alenia Space and demonstrate the effectiveness of the plans proposed by ActHyDiag

Automated generation of FDIR for the compass integrated toolset (AUTOGEF)

The ESA AUTOGEF (Dependability Design Approach for Critical Flight Software) study is a direct follow-on of the ESA TRP COMPASS (Correctness, Modelling and Performance of Aerospace Systems). The aim of COMPASS project was to develop a modelbased approach to system-software co-engineering, tailored to the specifics of critical on-board spacecraft systems. COMPASS included the development of a platform based on formal methods, which offers a wide range of techniques for system verification and validation. AUTOGEF aims to demonstrate that synthesis approaches can allow for effective automated FDIR development in accordance with the dependability requirements, through the implementation of an add-on to the COMPASS tool