Stability analysis of biped robot with direct control of zero moment point

This paper analyze a control strategy for simultaneously regulating the position of the ZMP and the joints of the robot. The unexpected rotation of the supporting foot is avoided via the control of zero moment point (ZMP). The proposed controller is based on a path-following control strategy, we used a class of ¿continuous time-invariant feedback controllers¿ to provide globally finite-time stability. The objective of the control law is based on tracking a reference path in the joint space instead of a reference function of time.