Three-dimensional geometrical measurement method and three-dimensional geometrical measurement system based on LED tag tracking

Abstract

The invention provides a three-dimensional geometrical measurement method and a three-dimensional geometrical measurement system based on LED tag tracking. A three-dimensional scanner is arranged such that the three-dimensional scanner can move along a track and is close to an object to be measured, and blocked local measurement is flexibly and conveniently carried out on a large-scale object by a structured light method to obtain a high-resolution local image. Meanwhile, as the light of an LED tag is bright enough, even when the distance between a stereoscopic tracker and the LED tag increases, the stereoscopic tracker can quickly and accurately track the LED tag to ensure that a server can precisely locate the center position of the LED tag and the position of the LED tag in the coordinate system of the three-dimensional scanner, precisely obtain the LED tag relationship between two local measurements, accurately evaluate the attitude change of the three-dimensional scanner and realize precise stitching of local measurement results. Moreover, three-dimensional measurement of the whole contour of a large-scale object can be completed conveniently, stably and accurately without the need for tedious switching between multiple projectors.

Description

technical field [0001] The invention relates to the technical field of three-dimensional measurement, in particular to a three-dimensional geometric measurement method and system based on LED tag tracking. Background technique [0002] At present, three-dimensional measurement technology mainly includes contact measurement and non-contact measurement. In industrial production, some large-scale workpieces can only use non-contact 3D measurement technology, such as ship curved steel plates. Non-contact 3D measurement technology includes two categories: visual camera 3D measurement and laser 3D measurement. The photographic three-dimensional measurement system has the advantages of fast measurement speed and high measurement density. The laser measurement system has the advantages of high measurement accuracy, but when measuring large-scale targets, the laser scanning speed is slow, which cannot meet the real-time requirements in industrial production. [0003] Visual measur...

AI Technical Summary

Problems solved by technology

In the large-scale steel plate three-dimensional measurement splicing system and method, on the one hand, the background projector needs to be set up in the sky to ensure that the special texture is projected on the entire surface of the steel plate. The light reflected from the surface of the steel plate into the 3D scanner becomes weaker. In this case, the background image collected by the 3D scanner will not be clear enough, which will bring troubles to the later image processing and data analysis, and then affect the 3D data of the steel plate and the quality of image stitching. On the other hand, it is necessary to switch between the two external projectors and the built-in projector of the 3D scanner during each partial measurement, which makes the entire measurement operation cumbersome and the system is quite inconvenient to use

Images