Ride comfort enhancement considering car body aerodynamics using actively controlled spoilers

The paper studies the application of aerodynamic actuators based on actively controlled spoilers mounted on the car body for enhancing the ride comfort of automobiles running on randomly uneven road surfaces. In particular this work extends previous analysis developed by one of the authors by considering the effect of aerodynamic forces induced by the pitch and bounce motions of the vehicle body itself. The design aspects of a wing actuator and the control law for optimising its performance is addressed. The control design considers the non-linearity due to saturation based on the SLQR approach using the stochastic linearisation technique. It is shown that under motorway driving conditions significant improvements in ride performance of automobiles can be achieved with the aid of actively controlled rooftop spoilers having a sufficiently fast response.