Application Research On Laser Tracing Multistation Measurement Technology

With the rapid development of ultra-precision machining and measurement technology,the performance requirements of large-scale ultra-precision equipment are getting higher and higher,especially for measurement accuracy.The rapid and highprecision calibration technology of the coordinate measuring machine(CMM)has become a scientific and key technology problem to be solved urgently.Laser tracing multi-station measurement technology,as one of the core technologies of ultraprecision measurement technology,puts forward higher requirements for its application in CMM calibration.The purpose of the subject "Application Research of Laser Tracing Multi-station Measurement Technology" is to study a method of spatial coordinate error correction of the CMM and the calibration method of positioning accuracy of rotating axis based on the measurement principle of laser tracing multi-station measurement system.The research of this subject provides an effective technical way to achieve rapid and highprecision calibration of CMMs.It also provides a technical reserve for solving the rapid and high-precision calibration technology of CMMs in large equipment manufacturing industry,and has a broad application prospect in the field of precision measurement.Based on the principle of laser interferometry ranging and tracing control,the mechanism of laser tracking multi-station measurement technology is analyzed.A spatial coordinate error correction method of the CMM based on laser tracing multistation measurement system is proposed.The spatial coordinate error correction value of any point in the CMM is obtained by inverse distance interpolation method.It effectively improves the measuring accuracy of the CMM.In order to calibrate the positioning accuracy of rotating axis of the CMM,a method of calibrating the positioning accuracy of rotating axis of the CMM based on laser tracing multi-station measurement technology is proposed.By using the error equation model of laser tracing multi-station measurement system,LevenbergMarquardt algorithm and the singular value decomposition transformation method of covariance matrix,the method realizes the optimization of laser tracer station coordinates,and achieves the calibration of positioning accuracy of rotation axis of the CMM by mapping the information of laser tracer station coordinates with the rotation angle of the rotation axis.In order to evaluate the spatial coordinate error correction results of the CMM based on laser tracing multi-station measurement system,a method for evaluating the uncertainty of spatial error correction system of the CMM based on laser tracing multistation measurement technology is proposed.The error factors affecting the accuracy of measurement system are comprehensively analyzed,and the uncertainty model of the measurement system is established.The uncertainty evaluation software of spatial coordinate error correction system of the CMM based on laser tracing multi-station measurement technology is developed,which realizes the correct evaluation of the system performance.Finally,some key technologies of this research are verified by experiments,including:(1)spatial error correction experiment of the CMM based on laser tracing multi-station measurement system,which verifies the correctness of uncertainty model of measurement system;(2)calibration experiment of positioning accuracy of rotating axis of the CMM based on laser tracing multi-station measurement system,which verifies the optimization effect of laser tracer station coordinates.The experimental results show that the calibration result of positioning accuracy of rotating axis is ±0.9" and the algorithm error of calibration method is 0.4".The calibration method proposed in this paper can calibrate correctly.