Fault-Tolerant Clock Synchronization with Drift Correction for Controller Area Network

Clock synchronization (CS) on the Controller Area Network (CAN) is important for enabling deterministic medium access for safety-critical vehicle applications. Existing CS methods on CAN rely on the synchronization of all nodes on a CAN bus to a single time master (TM). That is, if there is a fault in the TM, CS on CAN becomes impossible. In this paper, we propose a new fault-tolerant CS method with drift correction for CAN. Our method ensures that a faulty TM is detected and replaced by an alternative TM without any effect on the clock accuracy of all nodes on the CAN bus. Our method achieves a clock accuracy below 3 μs even in the case of frequent faults, which is confirmed by hardware experiments with fault injection.