Force Control System for an Automotive Semi-active Suspension*

A new semi-active suspension control system is proposed. This control system includes a Linear Parameter Varying (LPV) controller which was designed to improve the ride comfort. It also incorporates a Force Control System (FCS) to transform the force command from the LPV controller to a input signal for the Electro-Rheological (ER) semi-active damper. This FCS was assessed by its tracking performance of the desired force command, with a 7 % of tracking error. Then the semi-active control system was evaluated in a Quarter of Vehicle (QoV) model under two tests: a Bump and a Road Profile. The results were a reduction up to 19 % (Bump test) and 29 % (Road Profile test), of the sprung mass position compared with a passive suspension. Additionally, an improvement up to 14 % was obtained when compared with a LPV controller using a simple model inversion Force-Manipulation transformation.