Foot-guided agile control of a biped robot through ZMP manipulation

摘要

A novel biped control is proposed. It enables a robust foot-guided maneuver and suits to the locomotion in complex environments. It treats ZMP as an indirect manipulation variable rather than the control variable, and does not need to observe the acceleration. ZMP behavior is only constrained to approach the pivot foot during a step, so that the robot can flexibly accelerate itself. The most distinctive point to the previous methods is that the motion stability is guaranteed based on the capture point only at landing, which improves agility. The optimal input, i.e., the desired position of ZMP, is analytically obtained immediately from the current state of COM, time to land, and the desired landing position, so that it can be implemented with even less computation cost. Though the limitation of the supporting region is not explicitly taken into account, it is guaranteed that the desired ZMP is confined within the region based on its convexity.