抄録
In general, legs and crawlers are used as a robot to climb stairs. But, driving performance of these robots in the plains is lower than the wheel robot. The robot of this research runs level ground like a wheel and gets over a step with the wheel which unfolded. In this paper, we introduce a expandable wheel system, and it's described how to control for wheel expansion on the stairs. The control method has to be optimized. It is the first report to which we did a basic analysis.