In order to calibrate the position and orientation of laser displacement sensors mounted on a robot, an approach was devised for calibrating the position and orientation parameters simultaneously, based on the model of plane and sphere fitting. A contrast experiment was proposed and conducted systematically based on robot off-line programming and robot kinematics simulation. Effects on the accuracy of the two calibration algorithm were also analyzed such as the measurement error, length of sensor and the number of calibration parameters. Observability indices were introduced to evaluate the efficiency of parameter identification with the measurement configurations in robot motion space. Optimal measurement configurations and best evaluation index were calculated using on optimization algorithm. The effects of the non-modeling error and measurement error are reduced. The stability, accuracy and efficiency of the algorithm are improved. Experiment results of our improved calibration algorithm indicate that the standard deviation of position is 0.37 mm , the standard deviation of orientation is 0.35°．
YUAN Kang-zheng, ZHU Wei-dong, CHEN Lei, XUE Lei, QI Wen-gang. Approach for calibrating position of displacement sensor mounted on robot end-effector. JOURNAL OF ZHEJIANG UNIVERSITY (ENGINEERING SCIENCE), 2015, 49(5): 829-834.
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