Biped walking pattern generation by using preview control of zero-moment point

We introduce a new method of a biped walking pattern generation b y using a preview control of the zeromoment point ( Z M ) . First, the dynamics of a biped robot is modeled as a running cart on a table which gives a convenient representation to treat ZMP. After reviewing conventional methods of ZMP based pattern generation, we formalize the problem as the design o f a ZMP tracking servo controller. I t is shown that we can realize such controller b y adopting the preview control theory that uses the future reference. It i s also shown that a preview controller can be used to compensate the ZMP emor caused b y the difference between a simple model and the precise multibody model. The eflectiveness of the proposed method i s demonstrated b y a simulation of walking on spiral stairs.