Adaptive fuzzy coordinated fixed-time sliding mode control of full-vehicle active suspensions with linear motors

Active suspension systems can substantially improve ride comfort and vehicle stability; however, simultaneously suppressing body vibration, limiting suspension travel, and maintaining reasonable actuator demand remains challenging under model uncertainties and stochastic road disturbances. Permanent magnet synchronous linear motors are attractive for active suspension applications because of their fast dynamic response, direct force controllability, and energy-regeneration capability. This study proposes a novel control framework for a full-vehicle active suspension system driven by four permanent magnet synchronous linear motors. The framework integrates Prescribed-Performance Fixed-Time Sliding Mode Control with Active Disturbance Rejection Control to achieve rapid convergence, robust disturbance attenuation, and prescribed tracking performance. An Adaptive Fuzzy Comfort–Travel Coordinator further dynamically adjusts the nonlinear control gains based on instantaneous suspension operating conditions, coordinating the conflicting requirements of ride comfort and suspension travel. The proposed framework is evaluated under sinusoidal and ISO 8608 D-class road excitations and compared with three benchmark controllers. Simulation results demonstrate superior suppression of heave, roll, and pitch responses while maintaining acceptable suspension deflections and actuator demands. Under ISO 8608 D-class excitation, the proposed controller limits the maximum body displacement to 0.168 mm and achieves a frequency-weighted root mean square body acceleration of 0.155 m/s2 and a weighted vibration dose value of 0.380 m/s1.75. The actuator force and current demands also remain within the prescribed operating limits. These results demonstrate the proposed framework’s effectiveness in simultaneously enhancing ride comfort, vehicle attitude stability, and practical actuator feasibility.