Tire slip based integrated chassis control for enhanced limit handling

Abstract

This paper presents a tire slip based integrated chassis control (ICC) algorithm of four-wheel drive(4WD)/ electronic stability control(ESC)/electronic controlled suspension(ECS) for enhanced limit handling. The principal objective of the vehicle dynamic control algorithm for limit handling is to enable agile, steady maneuver at the limits and expand vehicle control capability to maximum. In order to achieve this objective, the ICC consists of three layers - a supervisor, an upper level controller, and a lower level controller. The supervisor determines desired vehicle motions based on driver commands to the vehicle. The upper level controller calculated virtual control inputs based on desired vehicle motion. In the lower level controller, the virtual control inputs are optimally coordinated to each chassis module based on tire combined slip for enhanced limit handling. The performance of ICC has been investigated via closed loop simulation and vehicle experiment. To investigate the ICC algorithm at the limits via closed loop simulation, the lateral driver model, which mimics professional drivers, for limit handling has been developed and utilized. In the developed driver model, body side slip angle incorporates into path tracking error in contrast to common path tracking algorithms. It has been shown that the proposed ICC algorithm effectively keeps stability and maneuverability of the vehicle at the limits.