Method for detecting concave-convex amount of aircraft assembly fastener

Abstract

The invention discloses a method for detecting the concave-convex amount of an aircraft assembly fastener, and relates to the technical field of aeronautical manufacturing surface quality detection, and the method comprises the following steps: S1, a detection device is built; s2, synchronous square wave signals are outputted to a line laser and a one-dimensional galvanometer to change the rotating angle of the one-dimensional galvanometer, wherein the one-dimensional galvanometer rotates in a stepping mode, and the line laser is lightened once every time the one-dimensional galvanometer rotates by one angle; s3, every time the line laser is turned on, the first camera and the second camera store images in a local exposure mode, and the sequence of local exposure is recorded; s4, after one-time scanning is completed, the first camera and the second camera transmit images, the images of the first camera and the second camera are matched according to the exposure time sequence, then three-dimensional calculation is conducted, and point cloud data of the fastener area are obtained; and S5, the point cloud data is analyzed, a high point and a low point in the point cloud data are extracted, and the concave-convex quantity is calculated. The method has the advantages of large data coverage area and accurate extraction of the high point and the low point during detection.

Description

technical field [0001] The invention relates to the technical field of surface quality detection in aviation manufacturing, in particular to a method for detecting the unevenness of aircraft assembly fasteners. Background technique [0002] A large number of fasteners such as rivets and bolts are used in the aircraft assembly process. The height difference between the nail head of the fastener and the surface of the aircraft is called the unevenness. For fighter jets, the unevenness affects the aerodynamic shape and stealth performance of the aircraft. During the construction of the piece, it is necessary to measure the concave and convex amount of the nail head. [0003] The usual measurement method is to use active vision to reconstruct the three-dimensional area of ​​the nail head to form the point cloud data of the area. Common methods include surface structured light method, multi-line laser method, cross laser method, etc. Among them, the surface structured light metho...

AI Technical Summary

Problems solved by technology

[0003]The usual measurement method is to use active vision to reconstruct the nail head area in 3D to form the point cloud data of the area. The common method is the surface structured light method. Line laser method, cross laser method, etc. Among them, the surface structured light method needs to project multiple images for phase analysis, which requires high computing power of the computing platform, and has a negative impression on the miniaturization and battery life of the platform. The multi-line laser method Dozens of laser lines are projected at the same time. The difference between the laser lines in the image is very small. Generally, the matching is performed by the order of the laser lines from left to right in the image. It is easy to be wrongly matched due to environmental interference, for example, because the actual shooting object is in the depth direction. The Nth laser line from left to right in the image is actually the N-1th laser line from left to right of the projection device, which will cause an error in the global calculation. The cross laser method only includes two laser lines , the data coverage area is narrow, and it is easy to cause inaccurate extraction of high and low points

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