ECU-level fault-tolerant framework for safety-critical FlexRay network systems

FlexRay, as a communication protocol for automotive control systems, is developed to fulfill the increasing demand on the electronic control units for implementing systems with higher safety and more comfort. In this paper, we propose an effective ECU-level fault-tolerant framework for safety-critical FlexRay network systems. The proposed framework employs the global redundancy scheme with the task migration to sustain the operation of system when the failure of ECUs occurs. Two types of task migration scheme are presented. One is the FlexRay cluster has no capability of task migration among backup (or called redundant) nodes and the other is contrary to that. We develop the reliability model for the analysis of our fault-tolerant FlexRay systems. 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.