Claw-Wheel: A transformable robot for search and investigation in amphibious environment

Abstract

This research develops an amphibious transformable robot, Claw-Wheel IV, which could move on flat ground, uneven terrain, and aquatic environment. Compared to the previous version, Claw-Wheel III, the new generation has waterproof enclosure to adapt to watery environments and paddles are installed to produce underwater propulsion force, while the transformable idea and claw locomotion mechanism design are retained. Different kinds of gaits are designed and compared to reduce the vertical fluctuation of COM of the robot and run more smoothly. Advancing in aquatic environments relies on the paddles driven along with the rotating claws while steering is achieved with velocity differential between claws on both sides. Velocities of individual claws are computed and regulated based on gyration radius and angular velocity parameters obtained in experiments, in order to follow ideal trajectories.