Abstract
In this paper, we describe the three legged climbing robot for inspection and maintenance of iron structures. The robot has three electromagnets at each leg in order to stick to a steel slope. It can climb the slope and trace a line on the slope by switching On/Off of the electromagnets properly. Legged robots usually have many actuators, and they are very difficult to control. In this paper, we developed a mechanism that can reduce the number of actuators with spring mechanism for link length adjustment. The length of a leg can be adjusted passively in order to satisfy a geometric constraint and also to put back the length of the legs after one stride. In this way, the robot has only three motors and can be controlled very easily. Effectiveness of the developed robot is shown by experiments.
