An Integrated System Design and Safety Framework for Model-Based Safety Analysis

Safety analysis is often performed independent of the system design life cycle, leading to inconsistency between the system design and the safety artifact. Additionally, the process of generating safety artifacts is manual, time-consuming, and error-prone. As a result, safety analysis often requires re- work, is expensive, and increases system development time. Several model-based systems engineering (MBSE) approaches have been developed to automatically generate certain safety artifacts. However, these approaches only cover part of the system design and safety life cycle. To truly leverage the benefits of MBSE, system design must be undertaken together with safety analysis for the entire life cycle, and multiple safety artifacts must be generated from the same model. Moreover, MBSE approaches that require a model transformation between the system design and the safety model suffer from the inability to automatically reflect changes made to a safety artifact in the system and the safety model. This paper presents a framework to integrate the entire system design and safety life cycle using an MBSE approach. Both the system design and the safety data are captured in a single SysML model, from which safety artifacts such as failure modes and effects analysis (FMEA) tables and fault trees are automatically generated. This framework ensures consistency between the system design and the safety analysis by requiring no model transformation, thus reducing the resources required for safety analysis. The proposed Integrated System Design and Safety (ISDS) framework comprises three phases that together cover the entire system design and safety life cycle. In this paper, the application of Phase 1 of the framework to a real-world case study is demonstrated.