Study of Self-Localization for Vertical Hole Elevation Robot in Lunar Environment

－Combination of Visual SLAM and Winch Odometry－

Abstract

Vertical hole elevation robot has been developed to explore a lava cave at Marius Hills on the moon. This robot is suspended from the lunar surface by a tether and enters the cave to investigate the environment by climbing up and down the cave wall. In this process, the robot needs to estimate its own position. In this paper, we propose a localization method for the robot using a combination of Visual SLAM and winch odometry. The accuracy of the proposed method was verified by experiments using a simulation environment. The accuracy of the proposed method and the validity of the model used in the simulation were verified in experiments conducted in real environment. As a result of the experiments, we got a prospect that the proposed method can perform localization in the lunar vertical hole.