A Lateral Control Method for Wheel-Footed Robot Based on Sliding Mode Control and Steering Prediction

Abstract

In order to improve the accuracy and enhance stability of the tracking system of wheel-footed robot, the lateral control problem in the process of wheel movement is discussed. First, according to the structure and movement characteristics of the robot, we establish robotic four-wheel steering dynamic model considering the linear profile of the tire. Second, a sliding mode control (SMC) method based on tracking expected yaw rate is proposed. A virtual path between the current position of the robot and the road is planned in real time. The current expected yaw rate of the robot is calculated according to the virtual path and the robot tracks the expected yaw rate through the SMC method. Using this method alone may cause that the robot could not able to track the path precisely, especially in the road with large curvature. Therefore, we add steering prediction control to achieve better lateral control. The simulation results show that the improved control method has a greater effect on the lateral control accuracy of the robot.