Damping of vehicle roll dynamics by gain scheduled active steering

Active steering is applied to robustly reduce the rollover risk of vehicles with an elevated center of gravity. An actuator sets an auxiliary steering angle which is mechanically added to the steering angle commanded by the driver. The control law presented, is based on feedback of the roll rate and the roll acceleration. The controller gains are scheduled with the speed and the vehicle´s CG height. The controller gains are found by the parameter space approach and constrained optimization in frequency domain. Robust reduction of transient rollover risk is shown by evaluation of the sensitivity function at various operating points. Simulation of a double lane change maneuver illustrates the benefits in time domain.