Automated Design Exploration and Dynamic Safety Analysis for Optimization of Mechatronic Systems in Safety-Critical Automotive Applications

The availability of safety-critical vehicle systems is essential to ensure passengers' safety in the context of automated driving and X-by-wire systems. The resulting safety-related availability requirements aim to maintain a minimum level of functionality also in the presence of component failures. In addition to electrification and the evolution of cross-domain functionalities, they also increase overall design complexity. Therefore, automated design space exploration, embedding automated safety analysis, becomes crucial for optimal system design. This article proposes a framework for model-based optimization of safety-critical mechatronic systems facing two major challenges as follows. 1) Modeling and exploration of a large design space resulting from topology variants and associated safety measures. 2) Dynamic safety analysis of each variant considering all component failures and their effects on relevant functionalities. Due to the high computational complexity, a two-level modeling approach combining behavioral and logical modules is introduced to reduce the number of evaluation runs when automatically exploring the design space. Further, an algebraic approach is proposed to calculate relevant safety metrics with high accuracy and comparatively low calculation time. The framework is exemplified by optimizing an electric powertrain over a nested design space considering acquisition and operation cost as well as different safety-related availability requirements.