Optical camera comprehensive calibration device

Abstract

The utility model provides a comprehensive calibration device for an optical camera, and belongs to the field of camera calibration. According to the technical scheme, the optical camera comprehensive calibration device comprises a calibration table top, a camera installation platform, a 2D calibration assembly and a 3D calibration assembly are arranged on the calibration table top, and the 2D calibration assembly and the 3D calibration assembly are both located in front of the camera installation platform and arranged side by side in the shooting direction of a camera to be calibrated. The camera installation platform is provided with a positioning structure corresponding to the 2D calibration assembly and the 3D calibration assembly. According to the special calibration device for the optical camera, 2D calibration and 3D calibration are integrated, independent equipment is adopted, calibration of the camera is independent into a special process, standardized operation is achieved, and calibration precision is improved; the calibrated camera is directly installed, the production process is optimized, and the assembly efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the field of camera calibration, in particular to a comprehensive calibration device for an optical camera. Background Art

[0002] In the field of machining, the demand for automation and intelligence is becoming increasingly prominent, which has led to the widespread application of various types of automated information collection equipment. Among them, equipment such as visual cameras and image processing systems play a pivotal role. Taking the laser cutting machine as an example, during its working process, whether it is benchmark positioning, edge finding or center finding, key operations can be achieved through high-precision visual cameras, thereby greatly improving processing efficiency and accuracy.

[0003] The accuracy of visual cameras is an important means to improve processing accuracy. Calibration of visual cameras to obtain the actual parameters of visual cameras is an important part of improving the accuracy of visual cameras. Camera calibration is generally done by setting acquisition targets, such as calibration plates, etc. The camera shoots the acquisition targets from multiple angles, and then obtains the camera parameters through data processing system calculations.

[0004] Currently, camera calibration is usually performed during the equipment assembly process, before the camera is installed. Firstly, the calibration device is mostly a single simple structure, and the calibration process is manual or a single uniform motion of the calibration plate, which is difficult to form a standardized process and has low accuracy. Calibration during assembly affects production efficiency. Secondly, visual cameras include 2D and 3D cameras, and the calibration processes of the two are also different. Therefore, it is difficult for assembly staff to fully familiarize themselves with the processes of the two, which affects the calibration accuracy. Summary of the invention

[0005] The utility model aims at solving the problems of non-standard calibration process, low calibration accuracy and complicated calibration of 2D and 3D cameras in the current visual camera calibration process, and provides a standardized, more efficient and more accurate optical camera comprehensive calibration device.

[0006] In order to solve the above problems, the technical solution adopted by the utility model is a comprehensive calibration device for optical cameras, including a calibration table, on which a camera mounting platform, a 2D calibration component and a 3D calibration component are provided. Along the shooting direction of the camera to be calibrated, the 2D calibration component and the 3D calibration component are both located in front of the camera mounting platform and arranged in parallel, and a positioning structure is provided on the camera mounting platform corresponding to the 2D calibration component and the 3D calibration component. This solution provides a special calibration device for optical cameras, which integrates 2D and 3D calibration, uses independent equipment, and makes the camera calibration independent as a proprietary process, thus realizing standardized operation and improving calibration accuracy; the calibrated camera can be directly installed, which optimizes the production process and improves assembly efficiency.

[0007] Preferably, the 2D calibration component includes a first rail mechanism, which is arranged along the shooting direction of the camera to be calibrated, and a first support seat is slidably mounted on the first rail mechanism, and a rotating platform is provided at the upper end of the first support seat, and a 2D calibration plate is hingedly mounted on the rotating platform, and the hinge axis between the 2D calibration plate and the rotating platform is a horizontal axis. The distance between the 2D calibration plate and the camera is adjusted by the first rail mechanism, and the calibration plate can be rotated and flipped up and down to adjust the angle of the photographed target.

[0008] Preferably, the 2D calibration component further comprises a first mounting seat, the first rail mechanism is mounted on the first mounting seat, and the first mounting seat is detachably mounted on the calibration table. The 2D calibration component adopts a modular design and can be detachably mounted on the calibration table as a whole, which is convenient for transportation and flexible in use.

[0009] Preferably, the 3D calibration assembly includes a second guide rail mechanism and a linear drive mechanism, the second guide rail mechanism and the linear drive mechanism are jointly mounted with a second support seat, and a 3D calibration plate is provided on the second support seat.

[0010] Preferably, the 3D calibration component further comprises a second mounting seat, the second guide rail mechanism and the linear drive mechanism are both mounted on the second mounting seat, and the second mounting seat is detachably mounted on the calibration table. The 3D calibration component adopts a modular design and can be detachably mounted on the calibration table as a whole, which is convenient for transportation and flexible in use.

[0011] Preferably, the 3D calibration plate is a glass calibration plate.

[0012] Preferably, the positioning structure includes a first positioning bar and a second positioning bar, the first positioning bar and the second positioning bar are respectively fixedly mounted on the camera mounting surface of the camera mounting platform and correspond to the 2D calibration component and the 3D calibration component respectively, and the first positioning bar and the second positioning bar are both arranged along the shooting direction of the camera to be calibrated. The side of the camera is against the first or second positioning bar, so that the camera can face the 2D calibration component or the 3D calibration component, and the camera positioning is more convenient.

[0013] Preferably, the positioning structure further includes a positioning plate, which is L-shaped and includes a flat plate portion and a straight plate portion, wherein the flat plate portion is fixedly mounted on the camera mounting surface of the camera mounting platform, and the straight plate portion is perpendicular to the shooting direction of the camera to be calibrated. The positioning plate contacts the front and rear surfaces of the camera, further limits the camera in the camera shooting direction, and improves the calibration accuracy.

[0014] Preferably, the camera mounting surface of the camera mounting platform is provided with a plurality of first mounting holes, the plurality of mounting holes are arranged in an array, the flat plate is provided with a second mounting hole, the second mounting hole is matched and connected with the first mounting hole. The position of the positioning plate can be adjusted according to the camera model.

[0015] Preferably, the four corners of the bottom of the calibration table are equipped with Forma wheels. The calibration table is leveled by the Forma wheels to ensure the horizontality of the upper surface of the calibration table and improve the calibration accuracy.

[0016] It can be seen from the above technical solutions that the advantages of the utility model are as follows: the device integrates the calibration functions of 2D vision cameras and 3D vision cameras into one, forming an independent calibration device and calibration process, with high calibration accuracy, which is convenient for batch calibration of various vision cameras. The calibrated cameras can be directly assembled and used, which optimizes the production process and improves assembly efficiency; the calibration device adopts modular assembly, and 2D calibration components and 3D calibration components can be selectively installed according to calibration requirements, which is convenient for disassembly, transportation and flexible to use; the camera installation platform can be close to and limit the surroundings of the camera to be calibrated, with good positioning effect, further improving the calibration accuracy. The use of this device can greatly improve the camera calibration accuracy and effectively improve production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solution of the utility model, the drawings required for use in the description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a structural schematic diagram of a specific implementation method of the utility model.

[0019] Figure 2 It is a structural schematic diagram of a 2D calibration component in a specific implementation manner of the utility model.

[0020] Figure 3 It is a structural schematic diagram of a 3D calibration component in a specific implementation manner of the utility model.

[0021] Description of main reference numerals

[0022] 1. Calibration table, 11. First positioning bar, 12. Second positioning bar, 13. Positioning plate, 2. Camera mounting platform, 3. 2D calibration assembly, 31. First guide rail mechanism, 32. Rotating platform, 33. 2D calibration plate, 34. First mounting seat, 35. First support seat, 4. 3D calibration assembly, 41. Second guide rail mechanism, 42. Linear drive mechanism, 43. Second support seat, 44. 3D calibration plate, 45. Second mounting seat. DETAILED DESCRIPTION

[0023] In order to make the purpose, features and advantages of the utility model more obvious and easy to understand, the technical scheme of the utility model will be clearly and completely described below in combination with the drawings in the specific embodiment. Obviously, the embodiments described below are only part of the embodiments of the utility model, not all of them. Based on the embodiments in this patent, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this patent.

[0024] like Figure 1-3 As shown, an optical camera comprehensive calibration device includes a calibration table 1. The calibration table 1 is a table structure, on which a camera mounting platform 2, a 2D calibration component 3 and a 3D calibration component 4 are installed. The lower part of the table can be set as a cabinet space for storing related tools and hardware equipment for data processing. The four corners (table legs) at the bottom of the calibration table 1 are equipped with Foma wheels, which can fine-tune the height. The camera to be calibrated is installed on the camera mounting platform 2, along the shooting direction of the camera to be calibrated (i.e. Figure 1 From left to right, set Figure 1 The left side is the rear and the right side is the front), the 2D calibration component 3 and the 3D calibration component 4 are both located in front of the camera mounting platform 2 and are arranged side by side.

[0025] Specifically, Figure 1 As shown, the camera mounting platform 2 includes two vertical plates arranged opposite to each other, and a top plate is installed on the top of the two vertical plates. The upper surface of the top plate forms a camera mounting surface, and a first positioning bar 11 and a second positioning bar 12 are installed on the top plate. The length directions of the first positioning bar 11 and the second positioning bar 12 are arranged along the shooting direction of the camera to be calibrated, and are used to limit the side of the camera to be calibrated. The first positioning bar 11 corresponds to the 2D calibration component 3 in the camera shooting direction, that is, when the side of the camera is in contact with the first positioning bar 11, its lens is facing the 2D calibration component 3; the second positioning bar 12 corresponds to the 3D calibration component 4 in the camera shooting direction, and when the side of the camera is in contact with the second positioning bar, the camera lens is facing the 3D calibration component. In addition, a plurality of first mounting holes are provided on the top plate, and the plurality of first mounting holes are distributed in an array. A positioning plate 13 is installed on the top plate through the first mounting holes. The positioning plate 13 is L-shaped, including a flat plate portion and a straight plate portion. A second mounting hole is provided on the flat plate portion. The second mounting hole is a long hole. The second mounting hole is matched and connected with the first mounting hole, and the straight plate portion is perpendicular to the shooting direction of the camera to be calibrated.

[0026] The 2D calibration component 3 includes a first mounting seat 34, on which a first guide rail mechanism 31 is provided. The first guide rail mechanism 31 is set along the shooting direction of the camera to be calibrated. A first support seat 35 is slidably installed on the first guide rail mechanism 31. A rotating platform 32 is provided at the upper end of the first support seat 35. A 2D calibration plate 33 is hingedly installed on the rotating platform 32. The hinge axis between the 2D calibration plate 33 and the rotating platform 32 is a horizontal axis. The first mounting seat 34 is detachably mounted on the calibration table 1.

[0027] The 3D calibration component 4 includes a second mounting seat 45, on which a second guide rail mechanism 41 and a linear drive mechanism 42 are provided. The second guide rail mechanism 41 and the linear drive mechanism are jointly installed with a second support seat 43, on which a 3D calibration plate 44 is provided. The 3D calibration plate 44 is formed by splicing two glass calibration plates together. The linear drive mechanism can use a ball screw, and its nut is fixedly connected to the second mounting seat 45.

[0028] The first mounting seat and the second mounting seat are both detachably mounted on the calibration table 1 by bolts.

[0029] The use process of the utility model is:

[0030] First, adjust the four Forma wheels to make the calibration table 1 in a horizontal state.

[0031] When performing 2D calibration, the first mounting base is pushed along the first guide rail mechanism to calibrate the field of view of the 2D camera. The 2D calibration plate is then rotated in the X-axis and Z-axis directions. Multiple calibration points are selected and photographed with the camera. The intrinsic parameters and external parameters of the camera are calculated using the calibration algorithm through the coordinates of the calibration points and the coordinates of the image to complete the calibration of the 2D camera.

[0032] When performing 3D calibration, the linear drive mechanism drives the second mounting seat to move, thereby driving the two glass calibration plates to move at a constant speed until the next instruction (speed change / stop). If there is still no next instruction when running to the front end of the stroke, it will reciprocate back and forth; during this period, it will continue to output position and speed information to the industrial computer for camera calibration; at the same time, the industrial computer will also receive information feedback from the camera and line laser based on the calibration board, select multiple calibration points and shoot with the camera, and finally use the calibration algorithm to calculate the camera's internal and external parameters through the coordinates of the calibration points and the image coordinates to complete the calibration of the 3D camera.

[0033] It can be seen from the above implementations that the beneficial effect of the utility model is that the device integrates the calibration functions of 2D vision cameras and 3D vision cameras into one, forming an independent calibration device and calibration process, with high calibration accuracy, which is convenient for batch calibration of various vision cameras. The calibrated cameras can be directly assembled and used, which optimizes the production process and improves assembly efficiency; the calibration device adopts modular assembly, and can selectively install 2D calibration components and 3D calibration components according to calibration requirements, which is convenient for disassembly and transportation and flexible to use; the camera installation platform can be close to the four sides of the camera to be calibrated, with good positioning effect, further improving the calibration accuracy. The use of this device can greatly improve the camera calibration accuracy and effectively improve production efficiency.

[0034] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An optical camera comprehensive calibration device, comprising a calibration table (1), characterized in that: The calibration table (1) is provided with a camera mounting platform (2), a 2D calibration component (3) and a 3D calibration component (4); along the shooting direction of the camera to be calibrated, the 2D calibration component (3) and the 3D calibration component (4) are both located in front of the camera mounting platform (2) and arranged in parallel; and positioning structures are provided on the camera mounting platform corresponding to the 2D calibration component (3) and the 3D calibration component (4).

2. The optical camera comprehensive calibration device according to claim 1, characterized in that: The 2D calibration component (3) comprises a first guide rail mechanism (31), the first guide rail mechanism (31) being arranged along the shooting direction of the camera to be calibrated, a first support seat (35) being slidably mounted on the first guide rail mechanism (31), a rotating platform (32) being provided at the upper end of the first support seat (35), a 2D calibration plate (33) being hingedly mounted on the rotating platform (32), and a hinge axis between the 2D calibration plate (33) and the rotating platform (32) being a horizontal axis.

3. The optical camera comprehensive calibration device according to claim 2, characterized in that: The 2D calibration component (3) further comprises a first mounting seat (34), the first guide rail mechanism is mounted on the first mounting seat (34), and the first mounting seat (34) is detachably mounted on the calibration table (1).

4. The optical camera comprehensive calibration device according to claim 1, characterized in that: The 3D calibration component (4) comprises a second guide rail mechanism (41) and a linear drive mechanism (42); the second guide rail mechanism (41) and the linear drive mechanism are jointly mounted with a second support seat (43); and a 3D calibration plate (44) is provided on the second support seat (43).

5. The optical camera comprehensive calibration device according to claim 4, characterized in that: The 3D calibration component (4) further comprises a second mounting seat (45), the second guide rail mechanism (41) and the linear drive mechanism are both mounted on the second mounting seat (45), and the second mounting seat (45) is detachably mounted on the calibration table (1).

6. The optical camera comprehensive calibration device according to claim 4, characterized in that: The 3D calibration plate is a glass calibration plate.

7. The optical camera comprehensive calibration device according to any one of claims 1 to 6, characterized in that: The positioning structure comprises a first positioning bar (11) and a second positioning bar (12), the first positioning bar and the second positioning bar are respectively fixedly mounted on a camera mounting surface of a camera mounting platform and respectively correspond to a 2D calibration component (3) and a 3D calibration component (4), and the first positioning bar (11) and the second positioning bar (12) are both arranged along a shooting direction of a camera to be calibrated.

8. The optical camera comprehensive calibration device according to claim 7, characterized in that: The positioning structure also includes a positioning plate (13), which is L-shaped and includes a flat plate portion and a straight plate portion, the flat plate portion is fixedly mounted on the camera mounting surface of the camera mounting platform (2), and the straight plate portion is perpendicular to the shooting direction of the camera to be calibrated.

9. The optical camera comprehensive calibration device according to claim 8, characterized in that: A plurality of first mounting holes are provided on the camera mounting surface of the camera mounting platform (2), and the plurality of mounting holes are arranged in an array; a second mounting hole is provided on the flat plate portion, and the second mounting hole is matched and connected with the first mounting hole.

10. The optical camera comprehensive calibration device according to any one of claims 1 to 6, characterized in that: The four bottom corners of the calibration table (1) are equipped with Fuma wheels.

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