Field calibration method of structural parameter of line structure light vision sensing system

Abstract

The invention provides a field calibration method of the structural parameter of a line structure light vision sensing system, comprising the following steps: (a) a movable plane target is put in a measured space, a collinear and three characteristic points with known mutual distance are arranged on the plane target, and the light plane which is projected by a line structure light projector intersects with the straight line at which the three are positioned so as to form a fixed point; (b) the collinear three characteristic points are used for setting up a three-point perspective model, and according to the mutual distances of the three characteristic points, the picpointed coordinates which are imaged on the image surface of a television camera by the three characteristic points and the fixed point, and the internal parameter of the television camera, the coordinate of the fixed point in the coordinate system of the television camera is computed; (c) the plane target is moved to many different positions within measuring range so as to respectively form a plurality of additional fixed points, and the step (b) is repeatedly carried out so as to respectively compute the coordinates of the additional fixed points in the coordinate system of the television camera; and (d) the fixed points which are obtained at many times are fitted into a plane so as to obtain the plane equation of the light plane in the coordinate system of the television camera, thereby completing the field calibration.

Description

technical field [0001] The invention relates to a calibration method for a line structured light visual sensing system, belongs to the field of photoelectric measurement, and is particularly suitable for on-site calibration of structural parameters of a line structured light sensing system. Background technique [0002] Line-structured light active sensing technology has the advantages of low cost, small size, non-contact, fast measurement speed, convenience and flexibility, and easy extraction of light strip image information. It has important significance and broad application prospects in the fields of visual measurement and industrial inspection. In the online structured light vision sensing system, calibrating the structural parameters of the vision sensor (that is, the positional relationship between the camera and the optical projector) is a necessary prerequisite for the vision sensor to perform 3D measurement. Similarly, studying the on-site calibration method of vi...

AI Technical Summary

Problems solved by technology

The above calibration methods generally have the disadvantages of requiring sophisticated calibration auxiliary equipment, high equipment cost, or cumbersome calibration process, and are not suitable for on-site calibration of visual sensor systems.

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