Abstract
Most humanoid robots lack of dynamic operations such as jumping and running motions. We aim to achieve development of a robot arm mechanism that can throw and pass heavy objects. We had developed a three linked compliant joints robot that has a mechanical adjustment mechanism of joint stiffness at each joint by using a non-linear spring element named as SAT (Stiffness Adjustable Tendon). SAT has a serious problem that the deterioration in the physical characteristics of SAT when significantly large tension is applied to SAT in long period of time. In order to prevent this problem, we had proposed a mechanism named as the Compliance Limiter that limits forcibly a stretching length of the SAT. Four types of three modes SAT with three steps of spring characteristics were developed. As a compliance limiter, a wire cable passes through the center of the SAT using an elastic cord. Because the wire of the compliance limiters is set inside the SAT, the structure is more compact.
