Kinematic calibration of a 3-DoF rotational parallel manipulator using laser tracker

TLDR: Kinematic calibration experiment results of this 3-DoF rotational parallel manipulator show that three angular deviations are improved from 1.97°, 0.24° and 1.75° to 0.10° respectively within the prescribed workspace.

Abstract: This paper proposes a laser tracker based kinematic calibration of a 3-degree-of-freedom (DoF) rotational parallel manipulator that would be applied in tracking and positioning fields. The process is implemented in this paper by four steps: 1) formulation of the geometric error model of this manipulator by means of screw theory considering all possible geometric source errors, which is followed by the verification of this error model employing SolidWorksź software. 2) sensitivity analysis of all geometric source errors based upon Monte Carlo method and remove some errors that have little influence on the pose accuracy of the moving platform in order to decrease the difficulty and complexity of the kinematic calibration. 3) error parameter identification and kinematic calibration experiment using laser tracker. 4) error compensation by amending controller model. Kinematic calibration experiment results of this 3-DoF rotational parallel manipulator show that three angular deviations are improved from 1.97°, 0.24° and 1.75° to 0.53°, 0.10° and 0.19° respectively within the prescribed workspace. Geometric error modeling based on screw theory is presented.The geometric error model is verified based upon the software method.Calibration includes sensitivity analysis, measurement plan and error identification.Software simulation and experiment are given to verify kinematic calibration flow.