Humanoid robot
Humans utilize the configuration with extended knees to achieve efficient walk. A humanoid robot, however, cannot do so, since this posture is a singular configuration. In order to tackle this problem, in our previous work, a walking pattern generator based on the spherical inverted pendulum model has been proposed. It enables to generate up-and-down waist motions and utilizes the singularity neighborhood in the middle of each support phase. However, the spherical inverted pendulum model cannot move the ZMP during each single support phase. To tackle this problem, we propose a new approach to generate a walking pattern based on a Spherical Inverted Pendulum model with an Underfloor Pivot (the SIPUP method). With this method, the ZMP gains mobility during each singleleg support phase, and walking with a smaller acceleration is achieved. In addition, it becomes easy to utilize singularity neighborhood. As a result, the knee joint can be almost fully extended (less than 0.01 rad). Experimental results show the effectiveness of our approach.
Dynamic Walk with SIPUP method: Video1 (1.2Mbyte) in 2007
Fig. 1 Observation by video image
Fig. 2 Walking motion of Hoap-1 with SC approach
References