A Proactive Nonlinear Disturbance Compensator for the Quarter Car

A new Proactive Nonlinear Disturbance Compensator (PNDC) for vibration damping in a quarter car is presented. A Flatness Based Disturbance Compensator (FBDC) for a nonlinear quarter car model is derived that decouples the chassis acceleration completely from the known road disturbance. This leads to a high level of driving comfort but to a loss in driving safety. Therefore a Proactive Linear Disturbance Compensator (PLDC) is added. This controller uses knowledge of the future road disturbance to reach a compromise between driving safety and driving comfort. The sensitivity of the nonlinear, proactive disturbance compensator to varying parameters or measurement noise is examined in simulations, and the tuning of the design parameters is shown. Furthermore, results from experiments on the institute's quarter car test stand are discussed. These have shown that the performance of the proposed method exceeds a linear quadratic regulator in simulations and experiments and that the driving comfort can be increased by more than fifty percent without a decrease in driving safety.