Owing to aging, the traffic accident, etc., leg inconvenient persons increase in number and many wheelchairs are used as a move means. However, a step and stairs are serious obstacles in that case. So, in order to break down an obstacle actively from person itself who is in a wheelchair, the wheelchair which going up and down stairs capability is developing. It corresponded to various stairs containing especially narrow and a steep slope stairs, without the care provider take, in order to particular note of man's reassurance and safety, and the leg and the wheel composite type were adopted and the cylinder was used as its motivity. In the model, in consideration of man's center of gravity, a simulation etc. performed and the norm of a main part design created.
