Differential-steering based path tracking control and energy-saving torque distribution strategy of 6WID unmanned ground vehicle

Abstract

The unmanned ground vehicle (UGV) is developing towards miniaturization, lightweight and intelligence. Path tracking and energy-saving control strategies are of great significance. In this study, a hierarchical control strategy is proposed to realize the path tracking control of six-wheel independent drive UGV (6WID UGV) based on differential steering, where actuator fault and energy-saving are considered. Firstly, a model free adaptive sliding mode control (MFASMC) method is utilized in the upper controller to estimate the required yaw moment. Then, in the lower controller, the seeker optimization algorithm (SOA) is utilized to achieve the torque distribution, realize the required yaw moment and longitudinal force, and reduce the energy consumption in the process of path tracking. The fault-tolerant control is considered in the torque distribution strategy to ensure the stability of 6WID UGV in case of motor execution fault. Finally, the effectiveness of the proposed scheme is verified by simulation under various operating conditions. The results show that the proposed method has better control performance, and the characteristics of energy-saving are optimized while ensuring the vehicle stability.