LAUSR

Abstract Aiming at simplifying the parameter calibration process of the 6 degree-of-freedom(6-DOF) parallel mechanism, improving the calibration efficiency, and reducing the calibration cost, this paper proposes a pose measurement device and method based on the Orthogonal Displacement Measurement (ODM) system. First, the pose calculation method of the proposed device is studied, and its forward and inverse kinematics solutions are solved using spatial analytic geometry method; second, an error model for the combination of the parallel mechanism and the ODM system is constructed using the infinitesimal displacement synthesis method; third, based on the proposed error model, a mathematical model is constructed for the optimization problem of the parameter error identification of the combination, wherein the minimization of the sum of squares of in, the indicating value displayed by the sensor, is taken as the objective function, and the structural parameter errors of the combination are taken as the design variables; at last, the ODM system is used to measure the pose of the 6-DOF parallel mechanism, and the OASIS software is adopted to directly find out the optimal solutions of the parameter errors and compensate them to the parallel mechanism control system, so as to complete the parameter calibration of the parallel mechanism. The comparison result of the pose errors before and after the calibration shows that, the maximum position error has been reduced by 69%-94%, and the maximum posture error has been reduced by 87%-97%. Using ODM system to calibrate the parameters of the parallel mechanism can not only effectively improve the positioning accuracy of the parallel mechanism, but also simplify the calibration work, improve the calibration efficiency, and reduce the calibration cost.