ESACS: an integrated methodology for design and safety analysis of complex systems

The continuous increase of system complexity - stimulated by the higher complexity of the functionality provided by software-based embedded controllers and by the huge improvement in the computational power of hardware - requires a corresponding increase in the capability of design and safety engineers to maintain adequate safety and reliability levels. Emerging techniques, like formal methods, have the potential of dealing with the growing complexity of such systems and are increasingly being used for the development of critical systems (e.g., aircraft systems, nuclear plants, railways systems), where at stake are not only delays in delivering products and economical losses, but also environmental hazards and public confidence. However, the use of formal methods during certain critical system development phases, e.g. safety analysis, is still at an early stage. In this paper we propose a new methodology, based on these novel techniques and supported by commercial and state-of-the-art tools, whose goal is to improve the safety analysis practices carried out during the development and certification of complex systems. The key ingredient of our methodology is the use of formal methods during both system development and safety analysis. This allows for a tighter integration of safety assessment and system development activities, fast system prototyping, automated safety assessment since the early stages of development, and tool-supported verification and validation