Design and experiments of a humanoid torso based on biological features

Among the components of a humanoid robot, a humanoid torso plays a vital role in supporting a humanoid robot to complete the desired motions. In this paper, a new LARMbot torso is developed for obtaining better working performance based on biological features. Through analyzing the anatomy of a human torso and human spine, a parallel cable-driven is proposed to actuate the whole mechanism by using two servo motors and two pulleys. Analysis are conducted to evaluate the properties of the proposed parallel cable-driven mechanism. A closed-loop control system is applied to control the whole LARMbot torso. Experiments in three modes are conducted by using the manufactured prototype for evaluating the characterizations of the proposed design. Results show that the proposed LARMbot can complete the desired motions. For general bending at different directions,the maximum bending angle is 40 degree, the maximum cable tension is 0.68 N, and the maximum required power is 18.3 W. In full rotation motion, the maximum bending angle is 30 degree, the maximum cable tension is 0.75 N, and the maximum power required is 20.5 W. This design is more simple and lightly, its low energy consumption and flexible spatial motion performance meet the needs of the humanoid robot torso's application in complex scenarios and commercial requirements.&#xD.