Visual stabilization of walking motion for biped robot with flexible ankles

This paper describes a vision-based method of walking motion stabilization for biped robot with flexible ankle joints. If the biped robot has some mechanical flexibility at ankle joints, then the ankle deformation can be detected from the visual target object position. This means the zero moment point(ZMP) can be related to the visual environment without any force sensor. However, there is possibility that the flexible joints cause the resonant oscillation while walking motion. Therefore, in our approach, the walking motion is modified according to the visual information for stable walk, and simultaneously the oscillated behavior is also perfectly suppressed by using the vision-based vibration controller. The validity of the proposed method without force sensor is evaluated by several experimental results.