A Mechanical Design for Efficient Hopping of Planetary Rover on Soft Soil

This paper presents a novel mechanical design for efficient traverse of hopping rovers. In order to continue the exploration of planetary environment without any human help, optimizations and efficient designs of rovers are essential. In particular, improving robustness and decreasing energy consumption are crucial aspects of rovers design. Hopping efficiency on sandy surfaces is strikingly worse than on hard ground, because such soil is deformed and easily causes slip. The purpose of this paper is to develop a novel mechanical design which can get enough friction from granular media. First, the effects of soft soil for hopping are studied by comparing with hopping on hard ground in terms of energy. Next, a novel foot pad design for hopping on planetary terrain is proposed. Inspired by the conventional wheeled vehicle design, treads, called grouser, are installed for the bottom of the proposed foot pad. The effectiveness of the proposed design is validated through experimental evaluation.