Research On Angular Measurement Accuracy Of Rotary-laser Scanning Measurement System

High-end equipment manufacturing industries such as aviation,aerospace,and shipbuilding are undergoing digital and intelligent changes,and large-scale precision measurement technology is also facing a series of challenges.Traditional large-scale measurement technology cannot meet the measurement needs of high-end equipment intelligent manufacturing.With high precision,automated real-time measurement,measurement range extension,and concurrent measurement capability,Workspace Measuring and Positioning System can help the high-end equipment manufacturing industry to transform to intelligence and has strong application potential in the intelligent manufacturing of high-end equipment.As a w MPS measurement unit,the angular measurement accuracy of the transmitter is a key factor that affects the dynamic and static measurement accuracy of w MPS.Based on the scanning angle measurement principle of the transmitter,we analyzed various factors that affected the angular measurement accuracy of the transmitter,including three aspects: the sub-period rotation fluctuation,the stability of the rotor shaft,and the scanning plane stability.The scanning angle measurement performance had been systematically studied and optimized,and the research content includes:1.The sub-period speed fluctuation of the transmitter directly affects its angular measurement accuracy.In order to evaluate the uniformity of the rotation speed of the w MPS transmitter in a single cycle,two sub-period rotation fluctuation measurement methods based on the differential algorithm and circle closure were proposed,which could eliminate the installation eccentricity and the manufacturing error of the grating and measure the real speed fluctuations.We analyzed the impact of the sub-period rotation fluctuation on the angular measurement accuracy of the transmitter by the angular measurement model of the transmitter,which provided theoretical support for the optimization of the scanning angle measurement performance of the transmitter.2.We analyzed the influence of the shaft stability on the angular measurement accuracy of the transmitter from the aspects of shaft runout and rotor whirl.We deduced the formulas of the angular measurement errors caused by shaft runout and established the rotor whirl model of the w MPS transmitter.We analyzed the influence of the rotor whirl on the angular measurement accuracy of the transmitter.For the drift of scanning plane parameters caused by the change of rotor whirl state,a corresponding compensation method was designed to improve the measurement accuracy of the w MPS.3.In order to study the influence of the stability of the scanning plane on the angular measurement accuracy of the transmitter,we analyzed the angular measurement error of the transmitter caused by the instantaneous changes in the thickness of the scanning plane and the flatness error.We adopted the inductive coupling power supply method to improve the stability of the scanning plane thickness,which reduced the angular measurement error caused by the change of the thickness of the scanning plane.In order to reduce the influence of the flatness error of the scanning plane,we designed a sub-regional calibration method that could accomplish error compensation for w MPS,which could improve the measurement accuracy of the w MPS.4.To improve speed stability and shaft stability,we utilized an upgraded speed control algorithm,a higher precision rotor balance design,and upgraded the shaft structure.We evaluated the optimized transmitter by the repeatability error of the scanning angle measurement.Utilizing the optimized transmitter,we built a large-scale intelligent measurement network at the aircraft manufacturing site,and completed measurement tasks such as aircraft segmented docking guidance and aircraft level state measurement.