On Eliminating Cumbersome Measurements in Semi-active Suspension Control of Ground Vehicles

The suspension system of a ground vehicle is responsible for isolation of the chassis or sprung mass from terrain disturbances. Suspension consists of a spring and damper. The spring deforms to the road undulations, relieving the chassis from following the road profile. The damper constituent in the suspension reduces the tendency of the spring mass system for resonance. It is well known in literature that, if the damper is made variable, the ride comfort can be improved substantially. Such a suspension wherein the damper is variable is called as semi-active suspension. Several algorithms are reported in literature for damper schedule, i.e., algorithm for choosing the right damping coefficient. To compute the desired damping coefficient, these algorithms need certain measurements as input. It is often cumbersome to obtain some of these measurements. This impacts the deployment of semi-active suspension, though it offers a superior ride comfort. This paper presents a novel algorithm for damper schedule where in, the need for such cumbersome measurements is eliminated. This algorithm is evaluated relative to the ones available in literature. It is seen that, this algorithm eliminates the need for cumbersome measurements without compromising on ride comfort and isolation performance.