Abstract
This paper describes an optimal trajectory planning of biped walking. Humanoid robots cost much energy with normal walking. It is important to develop energy-efficient walking and a control method of natural walking. We are interested in natural, high-speed and energy-efficient motion of organisms from a perspective of rehabilitation, medical treatment and engineering application. We obtained the optimal trajectory solution with a minimal square integral of input torque under the full-actuated condition with optimum trajectory planning method developed in our laboratory. Then, I developed a experimental robot and verified this method.