Controlled Anti-phase Synchronization of Passive Gait

Symmetry property of healthy gait in human walking has been applied to the analysis and design of the compass-like biped robot, as to explicitly explain the efficiency and control of human locomotion. A new control strategy of "anti-phase synchronization" has been presented here. The controller of anti-phase synchronization is able to solve the synchronization problem in such a way that the robot reaches a desired level of mechanical energy and its two legs move synchronously in opposite directions. With new presumption of the collision model, this control strategy can reduce the complexity of the hybrid dynamic system such as nonlinearity and strong coupling between dynamics of two legs. In addition to the discussion of the construction of a new Lyapunov function, simulation results have just proved the validity of the strategy. The method stated in the paper is helpful to practical application of the design of the robot\´s gait. To the best of our knowledge, it is the first time to introduce the concept of synchronization to explain and control the motion of passive biped theoretically.