Research On Non-contact On-machine Measurement System Based On Laser Micrometer

With the rapid development of science and technology,people have higher and higher requirements on the quality and precision of products,especially in the hightech field.Compared with the traditional simple surface,complex surface structure can better meet the functional requirements.Simplified system structure is conducive to reducing the quality and volume of the system.Problems related to the processing and manufacturing of complex surface have gradually become a hot research issue.Because complex surfaces are mostly used in precision manufacturing fields,such as aerospace,mold manufacturing,astronomical telescopes,etc.,higher requirements are required for their accuracy.The manufacturing of high precision complex surfaces cannot be separated from the high precision measurement system.Although the traditional offline measurement technology is relatively mature,it may introduce the positioning error which cannot be measured in the measurement process.This error has strong randomness,and it is difficult to make subsequent error compensation.In addition,offline measurement requires multiple clamping of the workpiece,which is not conducive to improving the processing efficiency.On-site measurement can effectively avoid the positioning error caused by multiple loading and entrainment.Aiming at the above problems,a non-contact in-situ measurement system based on laser micrometer is developed in this paper to avoid secondary positioning errors.The in-situ measurement system developed in this paper takes 3D moving platform as the carrier and combines with LK-H020 laser micrometer to collect surface data.Based on the principle of CMM,the functional requirements of the software system are analyzed.A non-contact in-place measurement software system is designed and developed by using the MFC module of VC6.0.Through the cooperation of each module,the three-axis motion control of the 3D motion platform and the data acquisition of the LK-H020 laser micrometer are realized.And connect and debug the software system and hardware system of the in-situ measurement system.In this paper,several measurement errors existed in the surface profile measurement are studied,and the corresponding mathematical models are established to compensate the error of the origin location and the rotation error of the probe.The evaluation method of surface shape is studied,which lays a foundation for subsequent measurement and analysis.This paper introduces the principle of locating points in trajectory planning,introduces several methods of locating points in trajectory planning based on the principle of locating points in trajectory planning,and uses MATLAB programming to simulate the corresponding algorithm.In this paper,the basic principles of sampling point planning are introduced,and the method of trajectory planning of measuring points is studied according to several important curve parameters of the curved surface,and the simulation experiment is carried out by using MATLAB software.According to the theoretical research and experimental research,the non-contact in-situ measurement system developed in this paper can realize the automatic measurement of various surface shapes and surfaces.Its measurement accuracy reaches micron level,and has high reliability and stability,which can meet the needs of high precision surface measurement.