An Effective Two-Level Redundancy Approach for FlexRay Network Systems

Abstract

FlexRay, as a communication protocol for automotive control systems, is developed to fulfill the increasing demand for implementing vehicle electronics with higher safety and more comfort. The applications of FlexRay drive-by-wire systems are often associated with human life, so the reliability issue of FlexRay network systems should be carefully studied. In this paper, we propose an effective two-level redundancy approach for safety-critical FlexRay network systems. The proposed approach demonstrates how to employ the backup nodes, mirrored tasks and task migration to sustain the operation of system when ECUs fail. We then perform the redundancy analysis and develop the analytical reliability models for the assessment of fault-tolerant FlexRay network systems in early design phase. The reliability analysis with various numbers of backup nodes, system sizes and ECU failure rates are conducted and the reliability results are provided and discussed. The contribution of this study is to propose a comprehensive fault-robust methodology with the analytical reliability model to support the development of safety-critical FlexRay network systems with an efficient manner.