Mobile mechanism of a climbing robot for cleaning and locomotion on stairs

In human living environments, it is often the case that the cleaning area is three-dimensional space such as a high-rise building. An autonomous cleaning robot is proposed so as to move on all floors including stairs in a building. When a robot cleans in three-dimensional space, it has to turn for direction in addition to climb down stairs. The proposed robot selects movement using legs or wheels depending on stair or flat surface. In this paper, a mobile mechanism and a control method are described for translational locomotion. The translational mechanism is based on a two-wheel-drive type omni-directional mobile mechanism. It is tested to recognize stair using the position sensitive detector (PSD), when shifts from translational locomotion to climbing down motion or edge-following motion.