Research On The Influence Of Network Consistency On The Measurement Repeatability Accuracy Of Industrial Photogrammetry

Based on the project "Development of ultra-high precision measurement system for large-size truss deformation and strain field",this paper proposes a scheme for measuring by industrial photogrammetry system for ultra-high precision measurement in special environment,and focuses on the network consistency in the scheme,and concludes that network consistency plays a significant role in the repeatability accuracy of industrial photogrammetry.The main work of the paper is summarized as follows:(1)Aiming at the ultra-high-precision measurement requirements of large-size trusses of space telescopes in special environments,the characteristics of the current industrial photogrammetry system are analyzed,and it is pointed out that the consistency of the measurement network plays a major role in improving the repeatability accuracy of industrial photogrammetry.The current research status of industrial photogrammetry technology,spacecraft thermal deformation measurement and industrial photogrammetry network is summarized.(2)The principle,composition and accuracy evaluation index of industrial photogrammetry system were expounded;The accuracy test of the new echo reflection mark is carried out,and it is concluded that the mark point has high roundness,which is conducive to the center positioning of the marker point and can improve the repeatability accuracy of industrial photogrammetry.The industrial photogrammetry mesh is studied,analyzed,tested and summarized,and combined with specific experiments to obtain a measurement mesh design method that can improve repeatability accuracy.(3)It is proposed to subdivide industrial photogrammetry network into network consistency and network robustness;The parametric representation and theoretical analysis of6 degrees of freedom were carried out to quantify the accuracy evaluation index of the consistency of the grid.This paper analyzes the relationship between deformation measurement and industrial photogrammetry in the field of industrial photogrammetry,and proposes a method for high-precision deformation measurement of the measured workpiece using a mechanical camera device.(4)According to the needs of shooting and measurement,a set of high-precision repeated positioning and posture shooting device was designed and developed,and its special control software was developed;The attitude repeatability accuracy of the shooting device was tested through the relevant experimental design,and the results showed that the attitude repeatability of the shooting device met the requirements,which provided data support for subsequent laboratory applications.(5)The relationship between network consistency and repeatability accuracy was tested and studied by using the shooting device in the laboratory,and the results showed that the measurement accuracy of the shooting device was at least twice as high as that of the previous manual shooting measurement;The preliminary conclusions obtained in the laboratory are verified and applied in the high-precision actual deformation measurement engineering,and the conclusions similar to those under laboratory conditions are obtained,and the measured accuracy meets the needs of the project.