SUMMERY OF THE UTILITY MODEL
In view of this, the present application aims to: a three-dimensional calibration plate and an image measuring apparatus are provided so that a three-dimensional camera can perform calibration more accurately and simply.
In one aspect, an embodiment of the present application provides a three-dimensional calibration plate, including: the positioning plate comprises a positioning plate body, wherein a plurality of positioning units are arranged on the positioning plate, the positioning units are all cylinders with the same size, and the positioning units are arranged on the positioning plate body in an array manner;
the positioning plate body is provided with at least two mounting holes for fixing the positioning plate body.
In some embodiments, the positioning unit is a cylinder, and the height direction of the positioning unit is perpendicular to the positioning plate body.
In some embodiments, the positioning plate body and the side of the cylinder for facing the three-dimensional camera are both provided with a matte coating.
In some embodiments, the distance between the geometric center of each cylinder and the geometric center of an adjacent cylinder is the same.
In some embodiments, the mounting holes are screw holes with an aperture size of M6, and the number of the mounting holes is six.
In some embodiments, the positioning plate body is composed of a lower part and an upper part, the positioning unit is arranged on the upper part, the lower part and the upper part are matched, two ends of the upper part form a step, and the mounting hole is arranged at the step.
In some embodiments, the upper portion, lower portion and positioning unit are integrally formed.
In some embodiments, the edges of the three-dimensional calibration plate body are chamfered.
In another aspect, the present embodiment provides an image measuring apparatus, including an apparatus body, and a three-dimensional camera mounted on the apparatus body, a mounting portion for mounting a three-dimensional calibration plate according to any one of claims 1 to 7 is provided in a range of being photographed by the three-dimensional camera, and the three-dimensional calibration plate is detachably mounted on the mounting portion.
The positioning unit arranged in the embodiment of the application is of a three-dimensional structure, the three-dimensional camera can determine the relative position according to the plane image, and can also be calibrated based on depth data, so that the links of operation are reduced, and compared with the prior art, the algorithm is simpler and has higher precision.
Detailed Description
In order to make the purpose, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be clearly and completely described below through embodiments with reference to the accompanying drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
The embodiment of the application is mainly applied to image measuring equipment provided with a three-dimensional camera, and the equipment can be production equipment, detection equipment and the like.
Referring to fig. 1 and 2, an embodiment of the present application discloses a three-dimensional calibration plate for being mounted on an apparatus for calibrating a three-dimensional camera by using an image measuring apparatus, including: the positioning plate comprises a positioning plate body 100, wherein a plurality of positioning units 200 are arranged on the positioning plate, the positioning units 200 are all cylinders with the same size, and the positioning units 200 are arranged on the positioning plate body in an array manner; and the edge of the three-dimensional calibration plate body is provided with a chamfer.
The positioning plate body is provided with at least two mounting holes 300 for fixing the positioning plate body.
The measurement principle of this embodiment is that the height of the positioning unit is determined, the distribution of the positioning unit is also determined, the three-dimensional camera can determine the horizontal position (of course, the distance can be determined according to the prior art) by shooting the two-dimensional image, the three-dimensional camera can be calibrated according to the height measured by the positioning unit, and the principle of measuring the height for calibration is that the data difference between the surface of the positioning unit relative to the surface of the positioning plate can be measured, and the calibration is performed according to the data difference and the known height of the positioning unit. Therefore, the calibration is more accurate, and the original algorithm is convenient to simplify.
In this embodiment, the locating plate body can adopt metal construction, adopts metal construction difficult to damage and warp, indirectly ensures the reliability of calibration. The positioning units 200 are arranged in an array, which may be a square matrix, or another array, etc. The positioning units may be equidistant or non-equidistant.
In some embodiments, the positioning unit is a cylinder, and the height direction of the positioning unit is perpendicular to a face of the positioning plate body, which is used for facing the three-dimensional camera. The cylindrical shape facilitates centering in image recognition, which can help simplify the calibration algorithm. The acute angle of the cylinder is less, so that the abrasion condition can be reduced.
In some embodiments, the positioning plate body and the side of the cylinder for facing the three-dimensional camera are both provided with a matte coating. The coating may be anodized brown, matte. Matte coatings are those having a gloss of less than 30% and a pigment volume concentration of greater than 45%, and are also known as flat coatings. The pattern layer formed by the matte coating can reduce the light reflection condition of the three-dimensional calibration plate and avoid inaccurate image measurement.
In some embodiments, the distance between the geometric center of each cylinder and the geometric center of an adjacent cylinder is the same. The algorithm can be simplified by using a regular matrix of positioning elements. It can be understood that even if the positioning pillars are irregular in position, the positioning pillars can be calibrated in an image measurement manner as long as the distribution situation of the positioning pillars is known in advance, but the algorithm is more complex compared with the regular matrix arrangement.
In some embodiments, the mounting holes 300 are screw holes with an M6 diameter, and the number of the mounting holes is six. The positioning plate can be more tightly installed on the equipment by adopting six installation holes.
In some embodiments, the positioning plate body is composed of a lower portion 110 and an upper portion 120, the positioning unit 200 is disposed on the upper portion 120, the lower portion 110 and the upper portion 120 are fitted at both ends of the upper portion to form a step 130, and the mounting hole 300 is disposed at the step 130.
In some embodiments, the upper portion, lower portion and positioning unit are integrally formed.
Referring to fig. 3, the present embodiment provides an image measuring apparatus, including an apparatus body 410, and a three-dimensional camera 420 mounted on the apparatus body, wherein a mounting portion for mounting the three-dimensional calibration board is provided in a range photographed by the three-dimensional camera, and the three-dimensional calibration board 430 is detachably mounted on the mounting portion.
The positioning unit arranged in the embodiment of the application is of a three-dimensional structure, the three-dimensional camera can determine the relative position according to the plane image, and can also be calibrated based on depth data, so that the links of operation are reduced, and compared with the prior art, the algorithm is simpler and has higher precision.
It is to be noted that the foregoing is only illustrative of the presently preferred embodiments and application of the principles of the present invention. It will be understood by those skilled in the art that the present application is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the application. Therefore, although the present application has been described in more detail with reference to the above embodiments, the present application is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present application, and the scope of the present application is determined by the scope of the appended claims.