Steering Tracking Control Based on Assisted Motor for Agricultural Tractors

One of the most important tasks in tractor navigation is the accurate steering tracking during field operations. Steering tracking is to achieve desired steering angle under the governance of the control action, it is essential for the operation quality of the tractor. The objective of this paper is to develop a steering tracking system based on motor control and propose steering tracking control method for automatically guided agricultural tractors. The steering column installed power motor is set up and the electronic control unit (ECU) is designed. As for the established steering system model, a modified Smith predictor structure based two degree of freedom control scheme is proposed. Steering tracking controller and disturbance rejection controller are derived by the analytical formulae on the basis of the internal model control (IMC) design principle and obtained with a simple and practical PID form. Simulation results demonstrated the efficiency of the proposed method for the steering tracking control system.