Abstract
The authors proposed and designed a robot for underwater work. The underwater robot has a rectangular plane body with 4 legs at each corner. The parallel link leg mechanism consists of 2 or 3 cylinders whose ends are attached to the robot body with free rotational joints. The ends of both piston rods are connected with pin joints. The movement of the leg which is composed of 2 cylinders is restricted to the forward and backward directions. However, the 3 cylinder leg can move in any direction. The authors studied the walking control scheme for this robot considering smooth and steady movement without rolling, pitching, yawing, and heaving motion while keeping the robot's body horizontal. The authors also confirmed the validity of the control scheme through simulation and experiments.
