Adaptive Steering Control Scheme for Combination Vehicles to Track Target Lane

In this paper, a new lane keeping control scheme of combination vehicles using tractor front wheel steering, tractor rear wheel steering and trailer wheel steering is proposed. At first, an estimator for unknown curvatures of target lanes is proposed. Because of using the estimate of road curvature, exact lane keeping can be achieved in steady state after changing road curvature. Next, a method to design ideal transient trajectories for lateral distance, relative yaw angle and relative combination angle is proposed. Then, an adaptive steering controller to achieve ideal trajectories is developed. The proposed controller doesn´t require any accurate knowledge of vehicle parameters. Because initial transient responses and lane keeping in steady state can be designed separately, good lane keeping performance can be achieved without using large initial steering angles