Low Jerk Control of Active Suspension for Ride Comfort

This paper deals with the problem of improving the ride comfort of vehicles when the road surface changes stepwise. We show that the ride comfort problem can be expressed as the standard <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$H_{2}$</tex> control framework. We consider using the jerk in the evaluation as well as the acceleration that is usually used for the ride comfort of vehicles. A controller synthesis method that simultaneously suppresses the acceleration and the jerk is proposed. The explicit use of the jerk in the evaluation causes some difficulties. We propose to modify the evaluation output to have physical and causal meaning to avoid the difficulties. With these modifications, we show that the problem can be reduced to a standard <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$H_{2}$</tex> control framework, and a dynamic state feedback controller is derived. The effectiveness of the proposed method is verified by a numerical example.