Sliding-mode control of active suspension systems: unit vector approach

This work presents the design of a sliding-mode controller (SMC) for an active suspension system. Sliding mode controller is applied to disturbance attenuation. Unit vector approach, which is a sliding mode control structure for multivariable systems, is used and a robust nonlinear controller is designed. Robust eigenstructure assignment method is implemented to sliding surface design. Extensive simulations are performed for a half vehicle model in which, the vertical and pitch motions of the mass supported by the suspension and the vertical motion of the suspension masses are considered. Simulation results verify the effectiveness of the proposed nonlinear controller scheme in comparison with the passive suspension system and H_∞ controlled active suspension system.