Pitch angle reduction for cars under acceleration and braking by active variable geometry suspension

This paper proposes a new concept of car active suspension that shows significant advantages with respect to previous systems. The Active Variable Geometry Suspension (AVGS) is based on a passive suspension, in which an extra link/chain of linkages is connected in series to the spring damper unit. One servo-motor per wheel is used to continuously and independently modify the position of the links in the mechanism in each quarter of the car, thus allowing to effectively control body motions. In order to demonstrate the potential performance of the concept, a state-of-the art non-linear full car model, which includes actuator dynamics and an adaptive pitch control system, has been developed. Results corresponding to acceleration and emergency braking maneuvers for a generic high-performance sports car are presented and show the effectiveness of the proposed suspension to control the pitch angle of the vehicle.