Image Recognition and Force Measurement Application in the Humanoid Robot Imitation

This paper studies and implements motion imitation interaction between a humanoid robot and a human. To achieve the implementation, three main processes are required. The first is the human motion data acquisition; the second is the motion data modification; and the last is the ankle angle adjustment on the supporting foot (or feet) of the humanoid robot. In the human motion data acquisition, we use a webcam to recognize the 13 marks that are pasted on the human's body and then calculate and record the relative positions of the marks for each motion into the motion database. In the motion data modification, the recorded motion data are modified by computer simulation to guarantee that the zero moment point of the robot is inside the stable region. Finally, based on the force sensor measurement on the soles of the robot, the ankle angles of the supporting foot (or feet) are adjusted such that the humanoid robot is capable of imitating the human motion with a balance status in real time. The experimental results demonstrate that the humanoid robot successfully imitates a series of human gymnastic motions.