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Research On Tool Path Planning Algorithms Of Toroidal Disk Cutter For Spherical Cylindrical Composite Lens Based On Optical Matching Parameters

Posted on:2020-07-31Degree:MasterType:Thesis
Country:ChinaCandidate:Y LiFull Text:PDF
GTID:2531307109473504Subject:Mechanical Manufacturing and Automation
Abstract/Summary:PDF Full Text Request
With the development of digital manufacturing technology,individualized customized manufacturing lenses have occupied more and more market share.However,the core technology of individualized customized manufacturing of refractive correction lenses has been monopolized by developed countries such as the United States,Germany,Italy and Japan for a long time,and the related manufacturing equipment basically depends on imports.Aiming at the customized manufacturing requirement of spherical-cylindrical composite lenses,this paper studies the path planning algorithm of toroidal disc cutter for the processing surface of spherical-cylindrical composite lenses,aiming at providing some reference for the processing technology and equipment development of customized refractive correction lenses.The main research contents are as follows:(1)Analyzing the surface of the lens and its main types,deducing the vector height equation of the machined surface of the spherical-cylindrical composite lens under the given matching’parameters and the optical parameters of the basic curved surface;giving the algorithm of Bspline surface modeling considering the error of B-spline surface modeling,making differential geometric analysis of the surface,giving the maximum and minimum principal curvature and effective curvature of the surface.The calculating formulas of differential geometric quantities such as normal vectors are given.At last,the main processing technology of lenses and the national quality inspection standard of lenses are given.(2)Combining the toroidal disc cutter with the B-spline surface constructed,the milling path generation algorithm of the toroidal disc cutter on the processing surface of spherical-cylindrical composite lenses is studied.The formulas for calculating feed step,calculating tool traveling distance,calculating cutter contact turning point,calculating formula for interference treatment and calculating formula for post-processing of five-axis NC machine tool with structure are W/C,Y,X,Z/T.Finally,the customized NC programming software for lens integrated manufacturing is developed by integrating B-spline geometric surface generation algorithm and tool path planning algorithm.The software takes user lens parameters as input and NC program as output.(3)The NC program of software output is simulated by using VERICUT commercial software.The results show that the NC program of software output meets the processing requirements.In order to explore the optimal cutting parameters,orthogonal experiments of PCD disc milling cutter with three factors and four levels were carried out.The roughness value was taken as the evaluation index of orthogonal experiments.The surface roughness of lenses under each orthogonal experiment was recorded by the roughness meter.The results of orthogonal experiments were analyzed and the reasonable cutting parameters were obtained.According to the experimental conclusion,the actual cutting process is carried out.Finally,the surface errors of the processed lenses are detected and evaluated by four coordinate measuring machine.
Keywords/Search Tags:Torus disk cutter, tool path planning, ophthalmic lens, B-spline Surface
PDF Full Text Request
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