Mechanical Challenges for Further Humanoid Robot Evolution

In this paper we develop two noble mechanisms for im proving the motions of humanoid robots The double spherical joint is a six DOF joint that consists of six sin gle DOF mechanical pairs in series with their axes inter secting at a point The double spherical joint replaces two hip joints six DOF of humanoid robot and even provides the equivalent function of waist joints without actually adding them The backlash clutch is a new joint drive mechanism and to be used in this paper for knee joints of humanoid robots The backlash clutch enables switching between drive and free modes The free mode will play a role in emerging humanoid behaviors that are dynamically coupled with the environments A humanoid robot is under development being equipped with the two mechanisms Results of preliminary experiments are to be shown