Robust H-infinity Fuzzy Output Feedback Control for Path Following of FWID-EVs with Actuator Saturation

This article introduces a robust H-infinity fuzzy static output feedback (RHF-SOF) control with norm-bounded strategy to enhance the path-following performance for the four-wheel-independent-driven electric vehicles (FWID-EVs). Firstly, taking the parameter uncertainties including vehicle mass, moment of inertia, longitudinal velocity, and tire cornering stiffness into account, a fuzzy optimization model is constructed to approximate the nonlinear characteristic of the vehicle system using both the parameter uncertainty reduction strategy and polytope reduction strategy. Secondly, with consideration of the difficulty of the online lateral velocity measurement, a Lyapunov stability-based RHF-SOF control with the gain scheduling method is proposed to control the variables of the path following. Thirdly, since the actuator saturation can deteriorate the control performances, a norm-bounded strategy is designed to address the nonlinear saturation problem. The proposed controller is verified and evaluated through the hardware-in-the-loop experimental test with different maneuvers.