SysML modelling of safety critical multi-technological systems

Within a case study it is shown that safety critical systems with mechanical, pyrotechnical, electric, electronics and software components can be modelled using system modelling language (SysML) diagrams. The diagrams are generated in an order that can be derived from heuristic principles. The principles are based on the development and safety life cycle, consistency requirements and practicality arguments. The principles are also fulfilled in a presented general modelling approach. The focus of the paper is on the order of the generation of the diagrams and the selection of modelling options. We describe which model diagrams are most advantageous for representing the multi-technological system and its interfaces. It is indicated how differences between the system and the model may arise and how they can be avoided. We also indicate how the SysML diagrams can be used for system failure modelling.