Etienne Prun

Thierry Lecomte, David Deharbe, Denis Sabatier et al.

Developing safety critical applications often require rare human resources to complete successfully while off-the-shelf block solutions appear difficult to adapt especially during short-term projects. The CLEARSY Safety Platform fulfils a need for a technical solution to overcome the difficulties to develop SIL3/SIL4 system with its technology based on a double-processor and a formal method with proof to ensure safety at the highest level. The formal method, namely the B method, has been heavily used in the railways industry for decades. Using its IDE, Atelier B, to program the CLEARSY Safety Platform ensures a higherlevel of confidence on the software generated. This paper presents this platform aimed at revolutionising the development of safety critical systems, developed through the FUI project LCHIP (Low Cost High Integrity Platform).

Thierry Lecomte, David Deharbe, Etienne Prun et al.

Industrial applications involving formal methods are still exceptions to the general rule. Lack of understanding, employees without proper education, difficulty to integrate existing development cycles, no explicit requirement from the market, etc. are explanations often heard for not being more formal. Hence the feedback provided by industry to academics is not as constructive as it might be. Summarizing a 25-year return of experience in the effective application of a formal method - namely B and Event-B - in diverse application domains (railways, smartcard, automotive), this article makes clear why and where formal methods have been applied, explains the added value obtained so far, and tries to anticipate the future of these two formalisms for safety critical systems.