Calibrating method of binocular three-dimensional measuring system

Abstract

A calibration method for a binocular stereo measurement system belongs to the technical field of measurement and testing. A plane calibration plate with an array of characteristic circles is used, in which the distance between the centers of two characteristic circles is accurately known; images are taken from the calibration plate at more than three angles; under the pinhole model, the linear method is used to solve the difference between the two cameras. The initial value of the internal and external parameters; considering the distortion effect, the first optimization is carried out with the internal and external parameters of the two cameras as the optimization variables; the spatial coordinates of the center of the feature circle on the calibration board are also used as the optimization variables for the second optimization; The ratio of the distance to the known precise distance scales the translation vector between the cameras to obtain the calibration result of this parameter. The internal parameters and relative pose parameters of the two cameras are the results of the second optimization. The method of the invention takes into account the influence of the geometric error of the calibration plate, reduces the requirements for manufacture and measurement and calibration of the calibration plate, and can obtain high-precision calibration results at the same time.

Description

technical field [0001] The invention belongs to the technical field of measurement and testing, and in particular relates to a method for calibrating internal parameters and relative position and attitude parameters of a binocular stereo camera oriented to three-dimensional measurement. Background technique [0002] Binocular stereo measurement refers to the method of imitating the visual function of human eyes, using two cameras to take images of the measured object from different angles, analyzing and matching the images, and calculating the three-dimensional geometric information of the object through the principle of triangulation. The binocular stereo measurement system is being more and more widely used in various fields such as reverse engineering, quality inspection, and vehicle guidance. [0003] The calibration of the binocular stereo camera refers to the process of obtaining the internal parameters of the dual camera and the relative position and attitude paramete...

AI Technical Summary

Problems solved by technology

(5) Self-calibration method, this kind of method does not need any calibration objects, and only calibrates the camera parameters through the constraints formed between images of static scenes with certain overlapping, although this method is the easiest to implement and has very high flexibility , but the calibration accuracy is difficult to meet the requirements of industrial measurement

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