Single-frame dynamic three-dimensional measurement method

Abstract

The invention relates to a single-frame dynamic three-dimensional measurement method, which comprises the steps of respectively encoding red, green and blue (RGB) color channels of an image to obtaina single-frame fringe pattern; projecting the single-frame fringe pattern to the surface of a to-be-measured object to obtain intensity distribution of the deformation fringe pattern; removing the background intensity of the deformation fringe pattern according to the intensity distribution of the deformation fringe pattern to obtain a deformation fringe pattern without the background intensity; carrying out normalization processing on the deformation fringe pattern without the background intensity to obtain a normalization processing result; processing the normalization processing result by using a Lissajous ellipse fitting method to obtain phase information of the to-be-measured object; and obtaining three-dimensional topography information of the to-be-measured object according to the phase information. According to the method, the phase information of the object is extracted through the Lissajous ellipse fitting technology and applied to a fringe projection system, the three-dimensional topography of the object can be reconstructed only by adopting the single-frame fringes, the calculation is easier and more convenient, and the reconstructed three-dimensional topography has high robustness and accuracy.

Description

technical field [0001] The invention belongs to the technical field of three-dimensional measurement of objects based on fringe projection, and in particular relates to a single-frame dynamic three-dimensional measurement method. Background technique [0002] In the field of 3D object surface measurement, 3D object measurement technology based on fringe projection technology has been widely used in various fields, such as industrial detection, face detection, medical plastic surgery, etc., due to its low cost, high precision, high reliability and Non-contact has become one of the most commercialized and efficient methods in 3D object measurement technology. This technology uses a projector to project fringes onto the surface of the object to be measured. Changes in the shape of the object to be measured cause the fringe to deform. The fringe deformation is analyzed and the phase information of the deformed fringe pattern is extracted to obtain the height information of the o...

AI Technical Summary

Problems solved by technology

Since multiple frames of fringe images are required to extract the phase of the object, it is difficult to achieve high-speed three-dimensional measurement; when measuring a moving object, the phase shift between the captured fringe images of the moving object is not uniform, which will lead to phase measurement errors; in addition, when When the object is moving, the time interval between frames cannot be ignored, so it will not be possible to capture the motion information of the object between frames, and then the absolute phase will not be obtained and the phase blur will appear. At this time, a large number of additional stripes are required for time phase expansion. to remove blurring, so real-time 3D measurement cannot be achieved

[0004] Single-frame methods, such as Fourier profilometry, only require one frame of fringe images to extract the phase information of the object. This method has advantages in fast measurement, but it is usually very sensitive to noise and surface texture changes and due to spectral loss. The reconstruction accuracy is not high

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