Visual Feedback Control Based on Optical Flow Vector Field for Biped Walking Robot

The paper presents a visual feedback control using optical flow vectors detected from camera image for biped walking robot. The authors have proposed the vision-based stabilization control for walking motion in the past research. In the approach, the zero moment point (ZMP) is related with the visual target position in the field of camera view, and the ZMP stabilizer using rotational motion around center of gravity is designed by image-based motion controller. For more improved performance of the motion stability, the optical flow field of the camera image is additionally employed for generating the recovery moment of modifying the ZMP, and it enable quick and stable recovery of ZMP against the disturbances. The validity of the proposed method is evaluated by several experimental results.