Research On Compensation Method For Tilt Error Motion Of Rotation Axis Of Articulated Arm Coordinate Measuring Machine

As a non-orthogonal coordinate measuring instrument,the articulated arm coordinate measuring machine(ACMM)is widely used in automobile manufacturing,aircraft assembly,mold manufacturing and other fields.The ACMM is in tandem structure,the measurement accuracy of ACMM is influenced significantly by the angular error of its rotation axis.In order to further improve its measurement accuracy,a new type of kinematic model is proposed in this thesis,and a set of data acquisition and processing software system is developed independently.The main research works and innovations of this paper are summarized as follows:1.A new type of kinematic model of ACMM is proposed.The measurement accuracy of ACMM influenced by tilt error motion of rotation axis is analyzed through simulation;the tilt error motion testing system is built and the error separation method is studied;Based on DH model,the kinematic model of ACMM with the tilt error motion compensation of the rotation axis is proposed.2.A kinematic parameter calibration model based on multiple feature quantity constraints,which has the advantages of single point and spatial distance kinematic parameter calibration model,is established.The kinematic parameter calibration algorithm of the ACMM combined with the LM algorithm is deduced in detail.3.A set of data acquisition and processing software system is designed to meet the experimental requirements of the tilt error motion test,structural parameter calibration,performance evaluation and other parts of ACMM is developed,the basic support for various experimental contents of ACMM is provided by the software system.Based on the above-mentioned error compensation method,experiments show that the measurement accuracy of the ACMM is up to 0.039 mm by using the kinematic model of ACMM with the tilt error motion compensation of the rotation axis.