Feasibility Study for a Vehicle-Trailer Backing Up Control 2004-01-2080

A rear-wheel steer-by-wire mechanism has been applied to assist driver on backing up a vehicle with trailer. To address the issues related to the mechanical limitation on the rear-wheel steering angle, a comprehensive feasibility study has been conducted using analysis and simulation. Four modes of steering (front-wheel only steering, rear-wheel only steering, rear-wheel angle which is slave to front-wheel angle, and four wheel steering for backing control) are compared in terms of various parameters, such as achievable path curvature and hitch angle. Four wheel steering achieves the largest curvature range. Sensitivity to the variation in trailer tongue length also has been investigated. It is concluded that a proper driver interaction mechanism is needed to further assist the driver, since the ±12 degree limitation on rear-wheel only steering may not provide full counter-steer capability.