An automatic detection method for machining accuracy of parts using 3D point cloud

Abstract

The invention discloses an automatic part processing precision detecting method utilizing a three-dimensional point cloud. Point cloud sampling is carried out on a part through a three-dimensional laser scanning technology; the sampling point cloud and a part design model are subjected to rough registering through a principal component analysis method, points are empowered according to the residual of the points in the sampling point cloud registering process, and registering intense adjustment is carried out through the method of closest point weight selecting iteration; finally, error distribution hypothetical testing and tolerance margin testing are carried out, and an evaluation result of the part processing precision is automatically generated. According to the automatic part processing precision detecting method, unqualified parts with obvious processing errors can be recognized through error distribution hypothetical testing, inferior-quality parts with the processing precisionexceeding the limited tolerance can be further recognized through tolerance margin testing, and the method has wide adaptability to automatic precision detection of traditional mechanical parts.

Description

technical field [0001] The invention belongs to machining detection technology, and in particular relates to an automatic detection method of part processing accuracy by using three-dimensional point cloud. Background technique [0002] Three-dimensional laser scanning is a three-dimensional space imaging technology that has developed rapidly in recent years. It uses a two-axis servo motor to drive a laser rangefinder to continuously sample the target surface of the scanning scene at equal intervals, and output a three-dimensional image that is completely consistent with the geometry of the three-dimensional scene. point cloud. This technology is being more and more widely used in surveying and mapping, archaeology, machining and manufacturing, three-dimensional printing, robotics, unmanned driving and other fields. [0003] Mechanical parts are the foundation of the manufacturing industry. Machining accuracy testing is a key production link to ensure the quality of precisi...

AI Technical Summary

Problems solved by technology

However, these methods do not take into account the overall deviation of the registration results caused by the machining error of the part surface when registering the scanned point cloud of the real object and the design model.

In addition, the detection schemes reported in the public are all directly calculating the surface deviation of the part on the basis of registration, and simply marking the result on the point cloud for display. Processing error

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