Calibration and Position Measurement of Robot Hand Using Vision Sensor

A robot has its original error of link length and angular offsets. Consequently, it has low adsolute positioning accuracy, although the robot has good repeatability. For this reason, calibration of manipulator is required. This paper proposes the calibration method using information obtained through a vision sensor, which is installed on the hand. First, the robot makes a series of movements with a vision sensor. Next, the sensor projects laser into an onject and takes an image at each position, and then 3D position of the spot on the sensor coordinates is obtained. Finally, parameters are calibrated using error of 3D position by the Newton method. Additionally, this paper shows the calibration results by the proposed method.