Application of component failure physics for the reliability assessment of an autonomous braking system

The growing demand for Cyber-Physical Systems (CPS) requires strong reliability. However, implementing Design for Reliability (DfR) in CPS requires a deep understanding of the components' Physics of Failure. In this work, an autonomous braking system, a Cyber-Physical System is chosen to demonstrate the application of failure physics for DfR of CPS. The component under investigation is a crystal oscillator in the control circuit of the braking system. By subjecting it to a temperature cycling that mimics the realistic environment of the component, its degradation is found to significantly increase vehicle stopping distances, thereby posing potential safety hazards. Importantly, the relationship between the oscillator's degradation and the stopping distance is non-linear, which is critical in avoiding simplistic extrapolations from initial degradation data to determine the time to replace the braking system. The outcomes of this study also provide essential design guidelines to enhance the reliability and safety of autonomous vehicle braking systems.