A Multimodal Amphibious Turtle-Inspired Robot with Wheel-Leg Composite Propulsion Mechanism

This paper shows a multimodal amphibious robot with wheel-leg composite propulsion mechanism (WLCPM), called AmphiTurtle-I, which achieves locomotion on land and in water with the same mechanism, with three locomotion modes: wheeled, legged and paddling swimming. The aquatic locomotion of the robot is inspired by the flattened flipper limbs of the turtle and the terrestrial locomotion is inspired by the wheel. By integrating these two types of locomotion, a WLCPM in the form of a disc with dynamically variable configuration is designed. The mechanical structure is designed and the kinematic analysis is carried out. The locomotion performance is discussed by fluid simulation and trafficability analysis. The prototype is used to carry out experiments on land and in water. Finally, AmphiTurtle-I successfully performs wheeled and legged locomotion on the ground and paddling swimming in an outdoor pond.