Abstract: Aimed at the calibration of line-structured laser mounted on manipulator, this paper presents a novel method, i.e., multiple coordinates transformation (MCT) for calibrating the hand-eye matrix. With the help of a laser tracker and reference object, the coordinates of end-effector and line-structured laser are measured with respect to laser tracker coordinate. Thus, the hand-eye matrix of laser coordinate with respect to the end-effector coordinate can be calculated indirectly and quickly. This method is easy to operate. It has the advantages of small errors, high precision, and low requirements for the experimental equipment. Experiments on the prismatic-rotational-prismatic (PRP) 3 degree-of-freedom robot arm mounted with line-structured laser are conducted. The results show that the rotational axis error is within 0.001, the rotational angle error is within 0.07°, and the translational matrix error is within 0.25mm. The method proposed can be used to calibrate the hand-eye matrix of any two or more degree-of-freedom manipulator mounted with two- or three-dimensional laser sensors.

Key words: line-structured laser, hand-eye calibration, serial manipulator, multiple coordinates transformation (MCT)