Design of a six-wheeled planetary surface locomotion system with single motor driving folded-deployed suspension

Abstract

Planetary exploration rovers are designed to perform challenging tasks in highly variable, rough terrain. Suspension is an important segment for locomotion system of exploration rover to distribute loads on wheels and enhance rover smoothness and terrain adaptability. Moreover a folded-deployed suspension has important meaning for reduction volume and enhancing carrying reliability of the rover. To design a folded-deployed suspension with minimized motor numbers for the planetary surface locomotion system of a six-wheeled rover, we present a dual rocker-bogie scheme that can multi-stage synchronously unfold driven by a single motor and clutches. Further we proposed the deployment manner, mechanical architectures and action program for the locomotion system. After analysis of the influence of suspension structure parameters selection, the suspension parameters in deployed configuration are optimized under constrains of the folded-deployed ratio and load sharing characteristic on wheels. The obstacle-climbing capability of the locomotion system is discussed by establishing quasi-static model and simulation. The effect of centroid pitching transformation of the locomotion system on the obstacle-overcoming capability and rover locomotion smoothness is evaluated by simulation.