Research On The Combined Measurement Method Of Laser Scanning And Laser Tracker

The manufacturing capacity of industrial equipment is the concentrated embodiment of national industry,science and technology and comprehensive strength,while the high-quality and efficient processing of large and complex structural parts is the key factor to guarantee the overall quality of equipment and shorten the manufacturing time.The traditional single detection is difficult to realize multi-region and online measurement.The integration and unification of various measurement methods combined with digital method can effectively improve system indexes such as field of view size and precision range in the measurement process.However,it is difficult to achieve high efficiency and precision measurement due to the difficulties in benchmark coordination between measurement systems and errors in data conversion and transmission.This paper is aimed at the processing of large equipment structural parts,and studies relevant compensation and calibration methods aiming at the high-precision measurement demand of differentiated precision demand zoning in the field of industrial measurement.The specific research is as follows: in order to achieve high-precision machining of large structural parts,it is necessary to carry out high-precision non-damage three-dimensional detection of the surface characteristics of the parts,and feedback the accurate surface structure characteristics to the IPC quickly,so as to achieve high-efficiency machining and registration.It is an important process of machining and assembly to accurately characterize and obtain the feature information of machined profile in any coordinate system and provide real-time feedback to the target drilling and milling equipment,which provides important reference for machining positioning and verification.Combined measurement has different advantages of various measurement instruments,which can help solve the problems existing in the measurement process of traditional single measurement instruments,such as long measurement cycle,limited measurement space and limited measurement target structure,etc.Due to the advantages in measurement accuracy and efficiency,it is gradually promoted in the field of large-size measurement.In this paper,aiming at the problem of large size of structural parts,different parts of precision requirements and high precision requirements,laser line scan and laser tracker are adopted to jointly measure and study the relevant compensation scheme and calibration algorithm.The main research contents are as follows:(1)In view of the initial positioning error in the process of local laser line scanning,the spatial point cloud transformation model was analyzed,and the local error compensation method based on three-dimensional transformation was proposed.According to the plane characteristics of the installation structure,the installation error bias matrix was obtained through three-dimensional coordinate measurement to complete the installation compensation.On the basis of the scheme,all the hardware lines are integrated and connected to add security equipment,and the target ball calibration device,local equal step control program and related data preprocessing program are designed to realize the dimension raising of two-dimensional data and compensation for accuracy.(2)According to local space optical reflection error problem,depending on the equipment to measure the optical principle and experimental conditions,by measuring the target model is put forward feedback real-time deflection Angle of the structure characteristics,to compensate the measurement data model based on optical compensation,eventually get precise local measurement point cloud data of systemic error compensation method.By comparing with the point cloud data measured directly,the average accuracy of the fitting radius can reach 10?m.(3)For large scale space problem,the three dimensional measuring global calibration is put forward based on laser tracking and combination of laser scanning large field of view global calibration method of analysis in the process of calculating the error term,proposed based on the estimation of singular value decomposition,solving model through the transcendental experiment analyzed the structure and characteristic parameters in the process of coordinate transformation algorithm selection influence on accuracy,improve public point data structure and local demand,realize the global calibration of the error within the 0.03 mm,compared with the traditional least squares,error is reduced on average by more than 60%.