Adaptive control with disturbance attenuation for hydraulic active suspension system

To deal with parametric uncertainties, external disturbances and uncertain coefficient before control input existing in the hydraulic active suspension systems, a design scheme is proposed for an adaptive controller with disturbance attenuation based on a quarter car suspension model. The adaptive controller is derived by a combination of selecting suitable Lyapunov function and non-linear backstepping control technique. It not only guarantees L 2 -gain performance for the external disturbance, but also overcomes the effect of parametric uncertainties of hydraulic actuator on the system. Meanwhile, loop nesting due to uncertain parameter before control input of system is solved effectively. Both theoretic demonstration and simulation results illustrate the effectiveness and feasibility of the proposed control scheme. And the comparison with the conventional PID controller indicates the robustness in transient performance, the improvement in ride comfort as well as the enhancement in handling and stability of vehicle.