Wheel-corner brake failures can significantly deteriorate vehicle stability and
safety, since unbalanced braking forces may introduce an undesired yaw moment.
This work investigates a fault-tolerant control strategy for Active Wheel-Corner
Systems, exploiting Four-Wheel Independent Steering (4WIS) to mitigate such
effects and preserve vehicle stability when brake actuator malfunctions occur.
Unlike many existing approaches, the proposed framework does not require
explicit fault detection or quantification as a prerequisite for corrective
action, eliminating potential delays and uncertainties associated with
fault-diagnosis schemes. A reference model for yaw rate and sideslip angle,
incorporating combined longitudinal and lateral dynamics, is proposed, and a
Weighted Pseudo-Inverse Control Allocation (WPCA) scheme is employed to
distribute corrective actions among the four steering angles according to each
tire’s capability, compensating for yaw moment imbalances caused by degraded
braking performance. The overall control framework is evaluated using a
high-fidelity vehicle model implemented through VI-CarRealTime, with control
algorithms and fault scenarios integrated via MATLAB/Simulink, providing a
flexible and realistic platform for systematic analysis. The strategy is tested
in cornering maneuvers with fault injection representing the worst-case scenario
of a complete failure of the outer-front wheel brake. Results demonstrate that
4WIS can effectively recover the desired vehicle response, reducing deviations
in yaw rate and sideslip compared to a baseline vehicle without reconfiguration.
The study highlights the potential of steering redundancy as a complementary
solution to braking and torque-vectoring systems for improving fault tolerance
in future Active Wheel-Corner systems.
