Design and development of a two-DOF torso for humanoid robot

This paper mainly describes the design and development of a two-DOF humanoid torso. “Up to down” sequence is adopted in our humanoid robot design. By analyzing human torso motion and employing a wheel platform to achieve stable operation, humanoid torso is designed with two identical joints and series configuration. Torso D-H parameters is obtained according to analysis of humanoid arms' workspace and binocular head's visual range. Mechanical structure of modular joint is described in detail, each torso-joint offers highly spatially integrated, minimal mass (10.9kg), better accuracy (0.01°) and enough load capacity (741Nm). Also, feasible control strategies are discussed. Meanwhile, a nice envelop is introduced to match anthropomorphic appearance requirement. In empirical part of this paper, two experiments have been carried out to verify the feasibility of torso-joint.