Three-dimensional measurement method and system based on optical grating projection unit and binocular polarization cameras

Abstract

The embodiments of the invention disclose a three-dimensional measurement method based on optical grating projection unit and binocular polarization cameras. The method includes following steps that:step 100, a polarizer is adjusted, so that an object image within a high dynamic range is obtained; step 200, the binocular cameras are calibrated, so that the internal parameters and external parameters of the cameras are obtained; step 300, the optical grating projection unit is set, so that stripes are projected onto the surface of a smooth object; step 400, stripe extraction and matching are performed, so that same-name points are obtained; and step 500, a three-dimensional model is reconstructed, so that the three-dimensional model of the smooth object is obtained. According to the methodof the invention, the coordinate information of the surface of the smooth object is obtained based on binocular stereoscopic vision space intersection, so that the accurate three-dimensional measurement of the surface of the smooth object is realized. With the method of the invention adopted, a saturation condition caused by the mirror reflection of the surface of the smooth object can be avoided; the applicable dynamic range of the system is improved; the calibration difficulty of the system can be reduced; and the operation cost of the system is reduced.

Description

technical field [0001] Embodiments of the present invention relate to the technical field of non-contact measurement, and in particular to a three-dimensional measurement method and system based on grating projection and binocular polarization cameras. Background technique [0002] Optical three-dimensional measurement technology can quickly and accurately obtain three-dimensional information of objects under non-contact conditions, and has been widely used in intelligent quality inspection, three-dimensional reconstruction, contour size monitoring and other fields. The three-dimensional measurement of grating projection is the most important part of optical three-dimensional measurement technology. It projects the grating fringes on the surface of the measured object, and processes the image acquired by the sensor to extract the phase information of the fringes, and obtain the three-dimensional information of the object by solving. [0003] The traditional grating projectio...

AI Technical Summary

Problems solved by technology

[0003] The traditional grating projection 3D measurement method works well for objects with rough surfaces, but has certain limitations for smooth objects

This is mainly because the fringe image acquired by the sensor is saturated due to specular reflection, and the sensor cannot effectively extract accurate phase information, thereby reducing the accuracy of 3D modeling

In addition, the grating projection three-dimensional measurement method based on a single sensor has extremely high requirements for system calibration. When the sensor or other system units need to be replaced, high-precision calibration needs to be performed again, which is costly and increases the operating cost of the system.

Images