Research On Large-scale Space Coordinate Measurement Location Technology Based On Optical Scanning

Three-dimensional coordinate measurement within large-scale volume is one of the basic supporting technologies in large-scale equipment manufacturing industry and precision engineering, which is also a hot difficult problem in precision measurement technology nowadays. There is an urgent need for field large-scale spatial coordinate measurement in heavy industry and basic industry due to the rapid development and the deepening degree of digitization. Considering the characteristics of industrial large-scale coordinate measurement, the aim of this thesis is to study problems of par-allel measurement with multi-station and multi-point, automatic identification of measuring points and the establishment method of the global measurement network, main research work contained in this thesis is as follows:1,Based on the analysis of theodolite intersection large-scale coordinate meas-urement system, an automatic coordinate measurement technique based on optical scanning was studied, and a system implementation is persented. Space angle meas-urement formula using new method is derived and coordinate measurement equation based on angle intersection measurement is build up.2,With the analysis of the impact of major error sources in current measure-ment system error transfer function of angle measurement is derived and transmitter's scanning plane parameters were optimized according to derived formula. Coordinate measurement error model was established, which studies the coordinate measuring error caused by angle measuring error. Moreover, an optimum measuring position of a two-station system was analysed. In addition,A system error correction method based on coplanar constraint was proposed3,Calibration method of transmitter station's structural parameters was imple-mented by using theodolites according to the spatial features calibration target was designed and the relevant calibration algorithm was studied. An orientation approach of transmitter stations in global measurement coordinate system based on coplanar constraint adjustment is presented; constraint equations were carried out and calcu-lated by levenberg-marquardt algorithm.4,Angle measurement function of system was validated. An optical scaning large-scale coordinate measuring system composed of two stations was used for measuring spatial position of aviatic jig platform. Leica laser tracker was also used to compare and verify the accuracy of scanning measurement system.