Integrated chassis control algorithm for maneuvering performance at the limits of handling

Abstract

This paper describes an analysis of handling characteristics at the limits of handling and rlrkan Integrated Chassis Control algorithm (ICC) of differential braking, front/rear traction torque, and active roll moment control. The integrated control algorithm is designed to maximize driving-velocity and enhance vehicle lateral stability in cornering. At first, maximum velocity is described based on vehicle dynamics and tire characteristics. Then, the nonlinear characteristics of cornering dynamics have been analyzed to investigate the performance of the chassis control module. An analysis of wheel slip angle is studied to enhance the vehicle lateral stability at high speed. The proposed Integrated Chassis Control algorithm consists of a supervisory controller, upper-level controller, and a lower-level controller. The supervisory controller monitors the vehicle status and determines desired vehicle motions such as a desired yaw rate, longitudinal acceleration and desired roll motion. The target longitudinal acceleration is determined based on the drivers intention and vehicle current state to ensure the vehicle lateral stability in high speed maneuvering. The control algorithm calculates a desired longitudinal force, yaw and roll moment for the generation of the desired vehicle motions. In the coordinator, actuator control inputs are coordinated to optimize the driving performance based on proposed strategies. An optimized-based control allocation strategy is used to distribute the actuator control inputs optimally under consideration of tire and vehicle limitation. Closed loop simulations of a driver-vehicle-controller system were conducted to investigate the performance of the proposed control algorithm. The performance of the ICC has been compared to those of individual chassis control systems, such as Electronic Stability Control (ESC), Four-wheel Drive (4WD), and Active Roll Control System (ARS). The simulation results show that the proposed ICC algorithm improve the performance in high speed cornering with respect to driving speed without losing stability compared to individual chassis control systems. Closed loop simulations with a driver-vehicle-controller system were conducted to investigate the performance of the proposed control strategy using CarSim vehicle dynamics software and the UCC controller coded using Maltab/Simulink.