Soil circulating system for a lunar subsurface explorer robot using a peristaltic crawling mechanism

Abstract

We have been developing an excavation robot for lunar subsurface investigations. The robot locomotion is based on the peristaltic crawling of an earthworm, which enables stable movement. The robot comprises three units: propulsion, excavation, and discharging units. In our previous research, we demonstrated that the propulsion and excavation units can excavate down to 650 mm without the discharging unit. However, when all three units were incorporated into the robot, excavation was limited by soil dropping from the discharging unit. To overcome this problem, we developed a novel soil circulating system. This paper presents the new system and experimentally verifies its feasibility. Finally, the contribution of the proposed system is confirmed in an excavation experiment. The robot's performance was remarkably improved by the system, and its excavation depth increased to 938 mm.