Design and Experimental Assessment of an Active Fault-Tolerant LPV Vertical Dynamics Controller

Abstract

This article addresses the design of an active fault-tolerant full-vehicle semi-active suspension controller by linear parameter-varying (LPV) control methods. The restrictive force constraints of the semi-active damper are modeled by saturation indicator parameters and treated as scheduling parameters in the LPV design. The synthesized LPV controller is subsequently augmented by a damper force reconfiguration exploring the weak input redundancy provided by four dampers in a full-vehicle application. In this way, the controller compensates for damper forces lost in the case of saturation or failure by the remaining dampers. The performance of the proposed LPV controller is validated by experiments on a four-post test-rig. The results show the improved tradeoff between ride comfort and road-holding of the full-vehicle LPV controller compared with a quarter-vehicle LPV controller and a Skyhook-Groundhook controller.