Section: Contracts and Grants with Industry

SSVAI Contract

SSVAI (Space Software Validation using Abstract Interpretation) is an ESA-ITI project (European Space Agency's Innovative Triangle Initiative) with Astrium Space Transportation, the CEA, the ENS, and the École polytechnique. The activity of the Abstraction project-team in this project is mainly to apply the Astrée static analyzer to the MSU (Monitoring Software Unit) code of the ATV (Automated Transfer Vehicle) for the ISS (International Space Station).

Upon completion of the project, we successfully analyzed several versions of a Scade model of the MSU controller compiled into C (including versions generated by different Scade compilers, and using different generation options). The study demonstrated the ability of Astrée to handle Scade-generated code. It showed that, although the library of abstract domains built in Astrée from our experience on avionics software is sufficient in some cases, achieving zero false alarms would require the development of new abstract domains adapted to the aspects of control theory specific to space control. However, it also showed that this could be mitigated by introducing a few numerical limiters at strategic locations in the code. Patrick Cousot and Radhia Cousot are the principal investigators for this action.