Research On Involute Tooth Profile Measurement And Stripe Quality Based On DMD Digital Grating

With the development of gear manufacturing industry,the requirements of gear measurement are more and more high and accurate.In order to solve the technical bottleneck that the tooth surface information is not fully expressed in the contact involute tooth profile measurement method,the structured light measurement method based on Digital Micromirror Device(DMD)will be attempted to introduce into the measurement field of the involute tooth profile with the research center of obtaining the full-field tooth surface information.Based on this,the research of control method,3D morphology reconstruction of involute tooth profile,tooth surface point cloud data extraction and digital grating quality testing and evaluation in 3D measurement of structured light based on DMD projection system will be focused in this paper.The specific research work includes the following aspects:According to the requirements of technical indicators,the DMD development system which can realize autonomous control is selected.Through the experimental research on the working principle of DMD and projection mechanism,the spatial frequency,phase and waveform controllable fringes can be projected.The synchronization of projection-acquisition is realized by the external trigger of electronic control.The experimental platform of the system was built based on the structured light projection principle of optical triangulation.The stereo calibration of the camera,DMD projection equipment and the built DMD-based digital grating measurement system was carried out by the method of projection complementary Gray code.The three-dimensional measurement of the object was realized based on the built digital grating measurement system,and the uncertainty of the dimensional measurement of the ceramic block and the shape error of the involute tooth profile are measured by extracting the experimental point cloud data,and a comparison experiment is established to verify the measurement accuracy of the experimental method.The full response mathematical model of the DMD digital grating projection system is analyzed,and the key system parameters that affect the quality of the projection fringe are obtained.The influence of the system parameters on the contrast and sinusoidal properties of the digital fringe in the DMD digital grating projection system is obtained by theoretical analysis combined with simulation and experiment.A comparison experiment with a physical grating was established to objectively evaluate the fringe quality of the structured light projection system based on digital grating.The experiment shows that the digital grating achieves the same precision as the physical grating projection fringe by setting the optimal system parameters.All technology research is about the optical method of measuring involute tooth profile encountered in the process of practical problems,which the main content of the research covers the development of new devices,new methods,break through the gear tooth surface precision of data acquisition technology problem,make the optical measurement method to replace the existing contact measurement method,optical gear measuring technology for the future lay the foundation of comprehensive development.