Several Common Geometric Quantity Detection Methods of Mechanical Parts Based on CT Slice

Abstract

The invention discloses a method for detecting several common geometric quantities of mechanical parts based on CT slices. The main steps are as follows: 1) Reconstructing two-dimensional industrial CT slices into a three-dimensional point cloud model STL. 2) Read the 3D design model of the workpiece to be measured, and perform sampling and surface fitting on the 3D design model, so as to obtain the types and characteristic parameters of each surface of the 3D design model. 3) Sampling each facet of the 3D design model to obtain a set of 3D sampling points. 4) Register the 3D point cloud model STL and the 3D sampling point set. 5) Segment the point cloud in the 3D point cloud model STL to obtain the point cloud segmentation result, so as to establish the corresponding relationship between the point cloud and each surface of the 3D design model. 6) Based on the point cloud segmentation results, perform benchmark selection and error calculation; 7) Compare the error calculated in step 6 with the tolerance value, and visualize the areas that do not meet the processing requirements. This patent provides a method capable of directly digitally detecting dimensions and several common form and position errors.

Description

Technical field [0001] The present invention relates to the field of mechanical parts detection, and in particular, several common geometric quantities detection methods based on mechanical parts of CT slices. Background technique [0002] The geometric measurement method of traditional mechanical parts, there is problems such as difficulty in measurement, time consumption, defective region mark. [0003] Based on digital detection manufacturing error analysis method, the digital measurement technology will generally use the surface geometry of the part to be tested into the point cloud model, and then match the three-dimensional design model, and finally calculate the part to be tested. error. However, this method can only be used to measure the distance of the specific model, or the distance between the overall point cloud and the standard model, the size error of the workpiece and the size error of the workpiece cannot be specifically analyzed. Inventive content [0004] It i...

AI Technical Summary

Problems solved by technology

However, this method can only be used to measure the distance from a specific point to the standard model, or the distance between the overall point cloud and the standard model, and cannot specifically analyze the size error and shape error of the workpiece.

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