Kinematics calibration method for series-parallel robot

Abstract

The invention discloses a kinematic calibration method for a series-parallel robot. The kinematic calibration method comprises the following steps that 1, a series-parallel robot geometric error modelis established based on a rotational amount theory; 2, the pose error of the tail end of the series-parallel robot is obtained based on the spatial position detection information of the laser tracker; 3, a geometric error source is identified on the basis of a Liu estimation method; and 4, error compensation is carried out step by step based on a correction controller output method. The kinematiccalibration method has the advantages of being high in precision and efficiency, convenient for industrial field application, and can be implemented on the basis of the robot tail end full-dimensional or few-dimensional pose error detection information; and according to the kinematic calibration method, an error model capable of meeting the completeness, the minimum and the continuity is established, the physical significance of model variables is definite, the ill-posed problem of the identification matrix is effectively solved, the identification precision of the error source and the stability of the identification result are improved, and therefore the compensation precision is improved.

Description

technical field [0001] The invention belongs to the field of robots, and relates to a kinematics calibration technology of an industrial robot, in particular to a kinematics calibration method of a hybrid robot. Background technique [0002] The five (six) degrees of freedom hybrid robot is a new type of multi-axis linkage processing equipment, which is built by a three-degree-of-freedom parallel mechanism and a two (three)-degree-of-freedom serial rotor. With the characteristics of large size and high rigidity, aiming at high-speed and high-precision machining, it has broad application prospects in the field of processing and manufacturing in large-scale non-structural environments. Hybrid robots such as Tricept and Exechon have been initially applied in aerospace, automobile manufacturing and other fields, and have achieved good results. [0003] Geometric accuracy is one of the important performance indicators of this type of hybrid robot. On the premise of good basic m...

AI Technical Summary

Problems solved by technology

First, this type of hybrid robot has a large number of joints, each joint has six error sources, and there are multiple structural errors between two joints. Second, this type of hybrid robot has an ill-conditioned identification matrix problem in the error identification process. The traditional identification method (such as the least squares method) has poor robustness and unstable identification results, making it difficult to achieve high-precision error compensation.

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