Helical surfaces are important elements of solid end mills. Their production is carried out using multi-coordinate grinding. Shape errors and reduction in the quality of the screw surface appear due to abrasion, high pressure, and wear of the grinding wheel. Therefore, it is extremely important to measure geometric accuracy, to perform linear and angular measurements, and to study the properties of rake helical surfaces. The paper proposes improvements to monitoring of helical surfaces via the use of a new computer vision system for assessing microtexture on helical surfaces after multiaxis grinding on CNC machines. A computer vision system was developed to evaluate defects on helical surfaces after multi-coordinate grinding on CNC machines, and a comprehensive analysis of existing indicators for recognizing the defect was carried out in a guaranteed range of probability of finding a solution of 99.7% for the distribution density of grinds. To verify the developed method, the accuracy of surfaces obtained by using the one was compared with the measurements carried out using specialized equipment for the control of the accuracy of helical surfaces. A new system for monitoring the accuracy and defects of cutting edges, helical front and rear surfaces allows establishing the main geometric parameters of the cutting edges and cutting wedge such as flute angle and rake angle at the apex using key indicators of the difference in color intensity in the focal zone of the image. When developing this approach, it was found that areas with smaller curvature of the rake surface are more susceptible to the accumulation of helical flute pitch errors after grinding. Experimental studies of the system operation were conducted to provide empirical evidence on helical surfaces after multiaxis grinding on CNC machines, demonstrating excellent convergence and defect recognition accuracy. The accuracy of determining the results of the inclination angles of the microtexture surface after grinding at the control point is 2-2.5 degrees, which allows you to form a comprehensive solution for scanning the surface, which will allow you to apply a simple method of control using a camera in reflected light.
The studies will be carried out using optical metrology methods on a Walter Helicheck inspection machine in reflected light and a number of images were stored to form a statistical sample. Established new indicators and criteria for grinding efficiency based on image processing of the helical groove of the end mill. As a result, recommendations for the selection of optical control techniques were made for the first time at the intermediate stage of technological preparation for production, in real time, and after processing. In this work, for the first time, we prove the possibility of determining the camera displacement pith distance during continuous scanning of the profile of a helical surface in a radial section, the measurement accuracy and recreating a three-dimensional model of the object. As a result of the work of the new algorithm using the Haar-wavelet with new indicators, it was established that the actual one is located inside the focal zone, which proves the possibility of applied application of the method of monitoring the shape of helical flute of end mills using computer vision. The measurement accuracy of the helical flute increased from 4 to 12% along its profile.
A method for microprocessing products with a shaped generatrix by remote the product from the image is proposed, which provides an increase in productivity without loss of quality. The method allows you to recreate an object based on image reconstruction with basic accuracy requirements and establish a rational trajectory of the turning tool on CNC machines. The method is implemented as follows: a cylindrical workpiece is fixed in the machine spindle, the plate is installed in the turning body cutter, a preliminary positioning of the cutter is performed and its fixation in the working area of the machine with a special trajectory of movement obtained on the basis of the recognized profile of the product during reverse engineering. As a result, the new method allows increasing the productivity of the treated surface up to 2 times, depending on the shape and accuracy of the object being reconstructed.
In this paper, a set of indicators for an effective assessment of the cutting ability of a grinding wheel was established based on the detection of the degree of filling and immersion of abrasive edges. It has been pointed out that a profile of a populated circle has a direct correlation with the average number of recognized faces. A new indicators for measuring zones with active edges and their distribution on the surface of a grinding wheel was developed, which can be identified by the models algorithms, is formed
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