Control of Ground Interaction at the Zero-Moment Point for Dynamic Control of Humanoid Robots

In order for stable control of humanoid robots, ground contact forces should be properly controlled for compensating the dynamic disturbances caused by unactuated body movement. The stability in the sense of the zero-moment point (ZMP), guaranteeing secure contacts during control, is a necessary condition for stable motion control. Therefore, we propose a method to control the ground interaction at the ZMP, or ZMP interaction in short, by modifying the system reference acceleration. We also show that simultaneous control of the ZMP interaction and the body movements is not allowed in general. Simulation result is provided to corroborate the theoretical result.