Line scanning profile measurement method and device based on liquid level benchmark

Abstract

The invention discloses a line scanning profile measurement method and device based on a liquid level benchmark. Colored liquid is adopted in an instrument as the generating medium of a scanning line, it is guaranteed that a measured object is in contact with the liquid level through a mechanical structure, an intersecting line capable of being adopted as the scanning line is generated at the junction position of the liquid level and the surface of the measured object, a calibrated camera is adopted to carry out image sampling on the scanning line, then the three-dimensional profile, corresponding to the intersecting line, of the measured object can be obtained through numerical solution, the measured object is controlled by a precision movable platform to be soaked in measuring liquid step by step, and therefore high-precision measurement on the three-dimensional shape of the overall measured object can be achieved. Due to the fact that the intersecting line of the colored liquid and the measured object is adopted as the scanning line, the defects that in a traditional line laser scanning method, the size precision of a laser knife edge is low, alignment of a plurality of sampling laser knives is poor, and measurement precision is limited by the optical feature of a measured object plane are overcome, the scanning line can be expanded within the 360-degree range of the measured object, and the line scanning three-dimensional measurement precision and speed can be improved.

Description

technical field [0001] The invention belongs to the field of three-dimensional measurement, and relates to a line-scanning three-dimensional profile measurement technology and a device thereof based on a liquid level reference. Background technique [0002] Line scanning three-dimensional measurement technology, due to its moderate measurement accuracy, good environmental adaptability, and strong adaptability to the surface texture of the measured object, has been widely used in some industrial measurement fields that do not require high precision. The line laser light source has good collimation and high brightness, and is the preferred scan line generating device in line scan measurement. The patent application No. 200910254430.5 proposes a method of using line lasers and multiple cameras to realize three-dimensional surface measurement with a large field of view. The patent with application number 200420120209.3 proposes an optical measurement method combining line laser...

AI Technical Summary

Problems solved by technology

Although these methods can realize the measurement of the three-dimensional surface shape of the measured object, the measurement accuracy is limited by factors such as the width of the laser line and the reflective characteristics of the measured object surface.

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