Abstract：An auto-calibration method was developed for planar four-cable parallel robots based on visual measurements. The end-effector pose is obtained using a camera fixed on the end-effector that measures the pose of AprilTags on storage racks. Geometric parameter identification and error compensation are then used for rapid calibration of the planar four-cable parallel robot. The system model is based on a kinematics model of the planar four-cable parallel robot for storage and logistics tasks. Then, the kinematics calibration method is used with the pose measuring method to calibrate the robot. The calibration accuracy was verified using both computer simulations and tests. The results show that this rapid calibration method provides positioning accuracy of less than 1 mm, which meets the accuracy requirement for the storage and stacking tasks.
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2022, Vol. 62 
