Bend pipe measuring and allowance locating method facing digital manufacture

Abstract

The invention relates to a bend pipe measuring and allowance locating method facing digital manufacture. The method comprises the following steps that multiple sensors are calibrated globally by meansof a laser tracker and a target, and coordinate systems of the sensors are unified into a global coordinate system; the sensors collect bend-pipe images and carry out edge detection and morphologicalrefinement to obtain a center line of the bend pipe in a strictly synchronous way, and 3D reconstruction of the center line is carried out in a bidirectional polar line matching algorithm; the centerline is dispersed into space point cloud, a control point, straightway end points and an arc center point of an arc segment are calculated, and 3D molding is carried out by taking the center line asa guiding line; and a design model matches a measurement model via a nearest point iteration method, the allowance position is calculated. Thus, self-locating cutting and welding of the bend pipe is realized, and the digital manufacturing process of the bend pipe is accelerated.

Description

technical field [0001] The invention relates to the technical field of computer vision, in particular to a digital manufacturing-oriented bending pipe measurement and margin positioning method. Background technique [0002] The pipeline system is an important lifeline in aviation, aerospace, automobile and other industrial fields. Like human blood vessels, it is responsible for the transmission of hydraulic pressure, air-conditioning, gas and other media. At present, the measurement methods for formed elbows are mainly contact methods, such as the profiling method , three-coordinate measuring machine, articulated coordinate measuring machine, etc. These methods have defects such as difficulty in manufacturing comparison devices, easy to cause damage or deformation, low efficiency, excessive reliance on the operator's subjective judgment, inability to reconstruct a 3D model, and no positioning reference. [0003] Advanced manufacturing technology is an effective means to tran...

AI Technical Summary

Problems solved by technology

[0004] Tang Zhengzong and others disclosed a bent pipe detection algorithm in the patent "a three-dimensional bent pipe multi-camera visual detection method and its system". The segmentation method of the arc segment is analyzed. Secondly, the elbow parameters are calculated in the disclosed algorithm, and the control point is obtained only by using the midpoint of the perpendicular line, and the end point of the straight line segment and the center point of the arc segment are not calculated.

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