Novel Kinematic Calibration and Fuzzy Gravity Compensation of an Industrial Delta Scara Robot

• Main Authors: Chi-Bin Chen, 陳旗斌
• Other Authors: 蔡清池
• Format: Others
• Language: en_US
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/n3pqe6

碩士 === 國立中興大學 === 電機工程學系所 === 106 === This thesis presents a new kinematic calibration method and a fuzzy gravity compensation approach to improving position accuracy of an industrial SCARA robot. Two calibration systems are developed using two laser displacement meters and an FARO laser tracker in order to conduct calibration experiments by sensing position information of the tool end point of a SCARA robot. After a four-step calibration procedure being proposed, a set of kinematic calibration equations are first derived in details, and then them are used to obtain corrected link lengths and angular offsets of the first two links of the SCARA robot. A fuzzy gravity compensation method is proposed to compensate for the height accuracy of the end-effector of the robot under a payload by using a set of if-then fuzzy rules. Several simulations and experimental results are conducted to validate the proposed kinematic calibration and fuzzy gravity compensation methods. In comparison with positioning accuracy before and after calibration, the proposed kinematic calibration method is able to effectively reduce the SCARA positioning errors, thereby significantly improving the absolute position accuracy of the SCARA robot. Through the experimental results, the fuzzy gravity compensation method is also shown effective in reducing the z-axis errors and increasing its practicability significantly.