An Experimental Comparison for the Accuracy Improvement of a 6-PSS Parallel Manipulator by Choosing Different Sets of Measurement Data

An experiment of kinematic calibration is conducted to improve the positioning accuracy of a 6-PSS parallel manipulator for large components assembly. To ensure the positioning accuracy of the manipulator with a higher level, the end effector's pose and position data, which are obtained by the laser tracker, are respectively used in the calibration. The accuracy improvements are compared between the usages of poses and position data and the result shows that though the measurement device has the capability of obtaining the six dimensional poses of the end effector, it is still better to use the position data rather than the pose data to do the kinematic calibration, especially for some large scaled components positioning, for the orientation error may make a bigger influence than the position error in the positioning of the end effector.