SysML extensions for safety-critical mechatronic systems design

Mechatronic systems become widely used as onboard systems with the development of electric and hybrid vehicles, more-electric aircrafts, etc. to achieve critical missions such as the control of these systems. The synergistic aspect of mechatronic systems makes their design challenging to take into account all the interactions among components of different domains. The safety-critical aspect of these systems implies rigorous safety analyses during the design. Consequently, designing such complex systems implies new tools and methodologies to manage the complexity and safety concerns while keeping within short time-to-market and budget constraints. Model-Based Systems Engineering (MBSE) and Model-Based Safety Analysis (MBSA) turn out to be compulsory for the design and safety assessment of complex mechatronic systems. However, they need to be integrated efficiently during the design process to avoid costly late design changes. In order to perform consistent and exhaustive system modeling and safety analysis of safety-critical mechatronic systems, the system model shall be extended to include additional information helping in the generation of safety artifacts. In this paper, we propose some SysML extensions to better model mechatronics specificities such as interconnection components and multi-physical interactions, as well as some safety aspects for a better integration of MBSE and MBSA. These proposals are applied to an Electro-Mechanical Actuator (EMA) for aeronautics industry.