Research On Micro-vision Based Spindle Rotation Error Measurement Method

Spindle rotation error of the machine tools is a main factor that influences the machining precision . It influences the shape precision, surface quality and Roughness of the parts. So it's necessary to measure the rotation error. This essay researched the conventional method of measurement and error separating technique, then proposed a micro-vision based method to measure spindle rotation error. This method doesn't require the use of master ball and spindle rotation errors can be measured directly. It can avoid separating setting-up eccentricity and shape error of master ball, therefore the measurement results will be more realistic and accurate..This essay summarized the source and the evaluation method of the spindle rotation error; introduced the measuring principle of the micro-vision; analyzed the measuring principle of the micro-vision based rotation error measurement, the system hardware composition and the software development environment. This essay researched image processing and character extracting algorithm for the image of the drone's movement locus, including image filter, adapter-threshold, connected region extracting, reticle stripes thining, sub-pixel line locating and the detailed process of extracting characteristic points. Also, this essay use two step method to calibrate the micro-vision measurement system based on analyzed imaging model of the camera and the features of the micro-vision system, provided the mathematical model for calibrating the camera lens's aberration and its operation. Finally, the calibration methods and rotation error measurement was verified with experiment, and the results of calibration and the rotation error of measurement results was given.