Modeling for Safety in a Synthesis-Centric Systems Engineering Framework

Abstract

The ever-increasing complexity of safety-critical systems puts high demands on safety assurance and certification. We focus on the development of control software, where safety) requirements engineering plays a crucial and delicate role. Nowadays, most of the safety features are ensured by the (embedded) control software and, consequently, a great deal of the operational failures primarily originate from requirement errors. We apply formal methods to systematically specify, model, and validate safety (control) requirements, which we then employ to automatically synthesize a control design based on a formal model of the system at hand. The synthesized designs are correct by definition, provided that the models capture all safety aspects of the system. We structure the process in a synthesis-centric model-based systems engineering framework that we apply in an industrial case study involving safe coordination of movement of theme park vehicles. The framework provides rigorous means for modeling of safety requirements, and it supports evolvable product design, requirement reuse, and early integration with hardware prototypes for validation and testing.