Torque Coordinated Control of Six-Wheeled Planetary Rovers Based on Wheel–Terrain Interaction

Abstract

Global interest in lunar exploration programs has heightened focus on the lunar South Pole region. With its complex terrain and irregular illumination, this region poses challenges for the mobility and energy management of planetary rovers. Consequently, to ensure adequate passing ability while minimizing energy consumption, research on the coordinated control of multidriven wheels is essential. In this study, a torque-coordinated control approach based on wheel–terrain interaction for a six-wheeled planetary rover is proposed. First, the continuous stress distribution model of the wheel–terrain interaction is simplified into an equivalent concentrated force model. Subsequently, precise and robust tracking of the desired velocity was achieved using a sliding-mode controller to overcome the challenges posed by model simplification and rough terrain. Subsequently, based on the expected torque obtained from the sliding-mode controller, with the optimization objective of minimizing energy consumption, the forces on the wheels were analyzed using the equivalent concentrated force model, and the torque distribution was coherently controlled. Finally, the effectiveness of the control method and the accuracy of the model are verified through whole-vehicle experiments, and the energy efficiency optimization ratio varies from 9.93% to 5.16% within the resistance range of 0–80 N.