The Research On Non-contact Measurement Method For Outer Diameter Of Thin-walled Parts

There is no special measuring instrument for thin-walled bearings in our country at present,and it is still measured by special instruments for general bearings.However,due to the limitations of general instruments,the measuring accuracy and accuracy can not meet the requirements.Therefore,this thesis takes thin-walled parts represented by thin-walled bearings as the research object,carries out the research of non-contact measurement of outer diameter of thin-walled parts,and develops a special non-contact measuring method for outer diameter of thin-walled parts measuring instruments.Firstly,the thesis analyzed the characteristics of thin-walled parts,especially thinwalled ring precision parts.On the basis of studying the advanced measurement methods of thin-walled parts represented by thin-walled bearings,and considering with the structural characteristics of thin-walled parts,a new measurement scheme was designed,which could avoid the spindle rotation errors existing in the past measurement process of outer diameter and roundness of ring parts.According to the requirement of measurement scheme,the design and modification of hardware(such as column,platform and adjustable bracket)of non-contact measuring instrument for outer diameter of thin-walled parts were completed,and the design and programming of supporting measuring software were introduced in detail.In this thesis,the non-contact measurement experiment of thin-walled parts outer diameter was completed,the measurement data was smoothed by filtering and compensated by calibration,and the measurement parameters of the system were optimized through experiments.Then,the model of measurement scheme was established,the factors affecting the measurement accuracy and their solutions were analyzed,and the measurement errors were analyzed by the theory of MATLAB and MSA(Measurement System Analysis).The results of experiment and analysis showed that the instrument and measurement scheme could complete the outer diameter measurement of thin-walled parts,and the measurement accuracy could meet the requirements of high precision measurement,and the measurement error was less than 2 microns.