From lamprey to humanoid: The design and control of a flexible spine belly dancing humanoid robot with inspiration from biology

Research on humanoid robotics has up to now been focused on the control of manipulators and walking machines. The contributions of body torso torwards daily activities have been neglected. To address this deficient area of humanoid robotics research, we developed a unique flexible spine biped humanoid robot. Inspired by the rhythmic and wave-like motions commonly seen in swimming lamprey and in belly dancing, we investigated the possibility of controlling the spine of our robot using the lamprey central pattern generator (CPG). Experimental results show that our robot is capable of mimicing both basic and complex spine motions with fewer actuators than the human spine and using only three input parameters (global and extra excitations from the brainstem, plane of actions). Our work suggests that the CPG is a suitable controller for humanoid spine motions because it can control a high degree of freedom mechanical spine with minimized control parameters. No complex computations of spine trajectories are involved. Furthermore, since our robot can move its upper body dynamically while standing and without external supports, it may be used as a prototype for the next generation of humanoid robots.