Fault-Tolerant Control of Electric Ground Vehicles Using a Triple-Step Nonlinear Approach

This paper investigates a triple-step approach-based fault-tolerant control (FTC) strategy for in-wheel motor electric ground vehicles, whose purpose is to preserve stability, improve handling with in-wheel motors and/or steering system faults. The proposed scheme is divided into two levels. The first level is the integrated vehicle motion control with model uncertainties, disturbances and the possible actuator faults, in which a triple-step nonlinear controller with on-line updating laws is designed. The second level is the driving reference signal generation, where the triple-step feedback law is used to provide a quantitative driving guidance and a residual signal with threshold for monitoring and evaluating drivers. The proposed FTC scheme not only achieves the vehicle safety but also the high-availability of the closed-loop driver-vehicle system. Simulation results show the effectiveness of the proposed scheme.