Authors: G. Zhengqi, L. Yufeng, W. Seemann
Addresses: College of Mechanical and Automotive Engineering, Hunan University, Changsha, Hunan 410082, China. College of Mechanical and Automotive Engineering, Hunan University, Changsha, Hunan 410082, China. Department of Mechanical and Process Engineering, University of Kaiserslautern, 67653 Kaiserslautern, Germany
Abstract: A nonlinear 5 degrees of freedom (DOF) system is used to model the dynamics of a four-wheel steering control vehicle. In the model, the yawing and roll motions of the sprung mass of the vehicle are considered and the nonlinear differential equations of motion are derived. In addition, the crosswind model and the driver model are established in this paper. They are used to investigate both the conventional front-wheel steering (FWS) and the four-wheel steering (4WS) vehicle during a crosswind disturbance. Two different 4WS control laws are used. The first is an open loop control law (OL4) in which the rear wheel steering angle is only determined by the front wheel steering angle. The second is a closed loop law (CL4) in which the rear wheel angle is determined by both the front wheel steering angle and the yawing angle of the sprung mass of the vehicle. Simulation results indicate that the CL4 system significantly improves the vehicle steering stability in response to a crosswind disturbance.
Keywords: vehicle; nonlinear dynamics model; crosswind; steering stability; simulation; steering control.
International Journal of Vehicle Autonomous Systems, 2003 Vol.1 No.2, pp.256 - 269
Available online: 18 Sep 2003 *Full-text access for editors Access for subscribers Purchase this article Comment on this article