Research On Visual Measurement System And Key Technology Of The Multi-corner Radius For The Bearing Needle Roller

As the basic components of machinery,bearing roller needles are widely used in aerospace,ships,precision instruments,and military industries.At home and abroad the automatic detection of the bearing needle roller's quality most focus on the diameter,length,the smoothness and other indicators of the needle roller,the current measurement of the radius of the bearing roller needle end fillet is rarely studied,especially the rounded face multi-corner radius.The size of the fillet radius at the end of the needle roller directly affects the force distribution of the bearing,which in turn affects the performance and service life of the bearing and even the entire mechanical device.With the improvement of the quality of bearing components and the advancement of intelligent manufacturing,the detection of the rounding radius of the needle roller bearing surface becomes more and more important.Therefore,the research on the multi-corner radius measurement system of the bearing needle roller end face not only promotes the production of bearing roller needles,but conducive to improving the status of China's manufacturing industry in the international arena.The article first introduced the position and current status of bearing roller needles in China's national production,and then studied the common measurement technology of the bearing roller fillet radius,compared the advantages and disadvantages of different detection technologies,and then for the measurement technology of roller bearing fillet radius is backward,the measurement accuracy is low,and the special bearing roller needle is not easy to measure.The advantages of vision measurement technology and some applications in the measurement of mechanical parts are introduced.To measure the radius of the roller bearing of the bearing roller by visual measurement technology provides the basis.Secondly,the visual measurement system of the bearing needle roller end surface rounding radius of was designed.According to the structure and technical characteristics of the bearing needle roller,the appropriate configuration of the PC computer,the LED surface light source and the vertical illumination method of the backlight,the CCD industrial camera and The optical zoom lens consists of a camera system,which is assembled to form the hardware part of the bearing roller fillet radius measurement system.Then chose LabVIEW as a development platform and completed the software algorithm design.The algorithm consists of two parts,one is the calibration algorithm that obtains the pixel equivalent through the measurement of the standard part;the other part is the rounding radius measurement algorithm,that is to use the template matching to locate the acquired image,and perform correction processing,and then choose median filtering to perform noise reduction on the corrected image through the comparison of noise reduction effects,and by comparing the edge detection effects of different edge detection operators,Canny operator is used to perform edge detection.Using the eight-neighbor boundary tracked to get the contour coordinates of the needle roller bearing end face,and the contour was interpolated by cubic spline interpolation in order to further smooth the contour.Then improving the L-curvature calculation method,and calculating the curvature of the bearing needle end profile.Using a clustering method to deal with the curvature of the extracted bearing contours to obtain a smooth transition point,and the radius of the roller needle was measured by the least-squares circle fitting.Finally,the experimental verification and analysis of the multi-corner radius vision measurement system were carried out.The experimental results show that the three roundness measurement accuracy of the system on the needle roller bearing end face is 0.002 mm,0.003 mm,and 0.002 mm,which satisfies the precision and reliability requirements of the testing.