Large-view-field camera combined calibration device and combined calibration method

Abstract

The large-view-field camera combined calibration device comprises a rotating assembly and a telescopic mechanism, the rotating assembly comprises a rectangular rotating plate, a groove is carved in the back of the rectangular rotating plate, a gear-rack transmission mechanism is embedded in the groove, and a shear type mechanism in the rotating assembly is matched. In actual operation, the calibration plate is fixed on the device through the right-angle sleeve, so that the calibration plate can be stably placed, and parameters such as the angle and the height of the calibration plate can be randomly adjusted at the same time. Compared with the prior art, the device is simple in structure, overcomes the defects that a handheld calibration plate is unstable and a fixed calibration plate is difficult to adjust at the same time, and generates an ideal effect in the measurement process of a large-view-field camera and the calibration process of a measuring instrument.

Description

Technical Field

[0001] The present invention relates to the field of large-field-of-view camera measurement and measuring instrument calibration, and in particular to a large-field-of-view camera combined calibration device and a combined calibration method Background Art

[0002] At present, camera calibration technology is already very mature and widely used in many fields, such as industrial inspection, robot vision, autonomous driving, medical image analysis, security monitoring, etc. Among them, in the field of visual measurement and precision measurement, camera calibration is an indispensable link. Camera calibration refers to the process of solving camera parameters, that is, imaging model parameters. It has the advantages of high measurement accuracy, application to augmented reality (AR), support for multi-camera systems, strong adaptability, and the ability to realize automated processing.

[0003] When the camera's measurement field of view increases, if a flat glass plate is used for calibration, the calibration plate needs to occupy the entire camera field of view, which means that as the camera's measurement field of view increases, the calibration plate must also become larger. However, the manufacturing difficulty and cost of large calibration plates will increase. In the camera calibration process, the traditional way of using calibration plates is usually to use a handheld method to change the position and angle of the calibration plate or to place it on a desktop or other fixed position. When using the handheld method, the operator needs to keep the calibration plate stable, and the calibration accuracy may be affected by slight shaking of the hand. In addition, the operator needs to avoid blocking the calibration pattern; when placing it in a fixed position, the position or angle of the camera may need to be adjusted to collect images at different angles, which may be inconvenient in some occasions. In the actual operation process, in order to obtain accurate calibration parameters, it is usually necessary to shoot the calibration plate from multiple angles, and ensure that the feature points of the calibration plate can be clearly identified in the captured images. Summary of the invention

[0004] Purpose of the invention:

[0005] In order to solve the problems mentioned in the background technology, the present invention provides a large-field-of-view camera combination calibration device and a combination calibration method. Through the mutual cooperation of gear-rack transmission, rotating components and scissor-type mechanisms, the purpose of stably placing multiple calibration plates and taking into account flexible adjustment is achieved, providing convenience for complex shooting operations.

[0006] Technical solution:

[0007] The present invention discloses a large-field-of-view camera combination calibration device, comprising a frame, the device also comprising a rotating assembly and a telescopic mechanism;

[0008] The rotating assembly includes a rectangular rotating plate and a ball joint, four circular grooves are provided at equidistant positions in the corner ends of the back of the rectangular rotating plate, four square grooves are provided on both sides of the circular groove parallel to the diagonal direction of the rectangular rotating plate, and the depths of the two intersecting square grooves are different, the ball joint transmission end is rotatably connected to the back of the rectangular rotating plate, and the base of the ball joint is installed on the frame;

[0009] The four corners of the rectangular rotating plate are respectively provided with telescopic mechanisms (), and the ends of the telescopic mechanisms () are connected to right-angle sleeves;

[0010] The telescopic mechanism includes a gear, a rack and a scissor-type mechanism. The racks are respectively embedded in four square grooves, the gears are embedded in circular grooves and mesh with the racks one by one, the end of the rack away from the ball joint is slidably connected to a side surface of the right-angle sleeve, the stationary end of the scissor-type mechanism is rotatably connected to the rectangular rotating plate, and its movable end includes two endpoints, one endpoint is rotatably connected to the other side surface of the right-angle sleeve, and the other endpoint is slidably connected to the other side surface of the right-angle sleeve.

[0011] Furthermore, the frame includes a plurality of main beams equidistantly arranged along the length direction, a plurality of secondary beams equidistantly arranged along the width direction, the secondary beams intersecting with and perpendicular to the main beams, a plurality of convex platforms fixed on the upper surface of the frame, the base of the ball joint is installed on the convex platform, and a plurality of groups of rotating components and telescopic mechanisms are installed on the frame without affecting each other.

[0012] Furthermore, the gear is controlled by a knob, and the position of the telescopic mechanism () is adjusted by rotating the gear to drive the rack. A locking device is provided on one side of the gear. When the telescopic mechanism is extended to a suitable position, the locking device locks the gear and fixes the telescopic mechanism.

[0013] Furthermore, the locking device includes internal threaded holes arranged at the four corner ends of the rectangular rotating plate and fixing screws matching the internal threaded holes. The telescopic mechanism is extended to a suitable position, and the fixing screws are screwed into the circular groove and locked tightly against the side of the gear.

[0014] Furthermore, a ball joint knob is provided at one end of the ball joint away from the rectangular rotating plate, and the ball joint drives the rectangular rotating plate to rotate to a suitable angle, and the ball joint knob is tightened to fix it.

[0015] Furthermore, a first limit groove is provided on one side of the right-angle sleeve, a second limit groove is provided on the other side of the right-angle sleeve, a protrusion is provided on the end of the rack away from the ball joint, and the protrusion is slidably connected in the first limit groove; the stationary end of the scissor-type mechanism is rotatably connected to the connecting column arranged on the side of the rectangular rotating plate, one end point of the movable end of the scissor-type mechanism is rotatably connected to the fixed limit column arranged on the right-angle sleeve, and a movable limit column is provided on the other end point, and the movable limit column is slidably connected in the second limit groove.

[0016] Furthermore, the scissor-type mechanism includes a left shear arm and a right shear arm, the left shear arm includes at least one movable porous scissor blade and one fixed porous scissor blade, the movable porous scissor blade and the fixed porous scissor blade are rotationally connected in sequence through axial holes, the right shear arm and the left shear arm have the same structure, and the fixed porous scissor blades are axially connected to each other in a scissor shape.

[0017] Furthermore, a protective groove is provided on one side of the right-angle sleeve where the calibration plate is placed, the top of the protective groove is set as a rounded corner, and the protective groove is made of rubber material.

[0018] Furthermore, the present invention discloses a combined calibration method of a large field of view camera combined calibration device, comprising the following steps:

[0019] Step 1: Set 4 sets of rotating components and telescopic mechanisms on the frame, with two sets in each row, and two rows in total, so that no two sets will affect each other;

[0020] Step 2: Adjust the direction of the rectangular rotating plate through the ball joint, adjust the length of the telescopic mechanism according to the size of the calibration plate, and set corresponding calibration plates on the right-angle sleeves at the ends of the four sets of telescopic mechanisms respectively;

[0021] Step 3: Tighten the ball joint knob and locking device to fix the current position of the calibration plate;

[0022] Step 4: Start combined calibration.

[0023] Beneficial effects:

[0024] The present invention realizes multi-degree-of-freedom adjustment through the design of ball joints and rotating components, and users can easily change the position and angle of the calibration plate as needed. This flexibility allows rapid adaptation to different shooting scenes, improving the applicability and convenience of the calibration process. At the same time, the transmission system composed of gear 1 and rack can accurately control the distance between the right-angle sleeve and the rotating component. This mechanism is not only easy to operate, but also can ensure that the calibration plate is firmly fixed in the desired position, thereby ensuring the consistency and accuracy of the calibration data. At the same time, the present invention supports the simultaneous use of multiple calibration plates. The device can process four calibration plates in different postures at the same time, which greatly increases the amount of data that can be obtained in a single calibration process, and helps to improve the accuracy and robustness of the calibration results. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is an overall schematic diagram of the present invention;

[0026] Figure 2 It is a front view of the rotating assembly and telescopic mechanism of the present invention;

[0027] Figure 3 It is a rear view of the rotating assembly and telescopic mechanism of the present invention;

[0028] Figure 4 It is a schematic diagram of the structure of the rotating assembly and telescopic mechanism of the present invention;

[0029] Figure 5 It is a front cross-sectional view of a rectangular rotating plate of the present invention;

[0030] Figure 6 This is a schematic diagram of a square groove according to an embodiment of the present invention;

[0031] In the figure, 1 is a frame, 2 is a main beam, 3 is a secondary beam, 4 is a rotating assembly, 41 is a rectangular rotating plate, 42 is a ball joint, 421 is a ball joint knob, 43 is a convex platform, 44 is a circular groove, 45 is a square groove, 5 is a telescopic mechanism, 51 is a gear, 511 is a knob, 512 is a locking device, 513 is a fixing screw, 52 is a rack, 521 is a protrusion, 53 is a scissor mechanism, 531 is a left shear arm, 532 is a right shear arm, 533 is a movable porous scissor blade, 534 is a fixed porous scissor blade, 54 is a right-angle sleeve, 541 is a first limiting groove, 542 is a second limiting groove, 543 is a fixed limiting column, 544 is a movable limiting column, 545 is a connecting column, 546 is a calibration plate, and 547 is a protective groove. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0033] like Figure 1-Figure 5 As shown, the present invention discloses a large-field-of-view camera combination calibration device, comprising a frame 1, the device also comprising a rotating component 4 and a telescopic mechanism 5;

[0034] The frame 1 includes a main beam 2 arranged in the center along the length direction, and a plurality of secondary beams 3 arranged equidistantly in the width direction. The secondary beams 3 intersect and are perpendicular to the main beam 2. A plurality of convex platforms 43 are fixed on the upper surface of the secondary beam 3. The base of the ball joint 42 is installed on the convex platform 43. A plurality of sets of rotating components 4 and telescopic mechanisms 5 are installed on the frame 1 without affecting each other. In this embodiment, there are four sets of rotating components 4 and telescopic mechanisms 5, which are installed on the secondary beam 3 in a clockwise manner and at equal distances, so that this embodiment can install four calibration plates at one time to carry out photography work.

[0035] The rotating assembly 4 includes a rectangular rotating plate 41 and a ball joint 42. Four circular grooves 44 are provided at equidistant positions in the inner corners of the back side of the rectangular rotating plate 41. Four square grooves 45 are provided on both sides of the circular grooves 44 parallel to the diagonal direction of the rectangular rotating plate 41. The depths of the square grooves 45 intersecting with each other are different. The transmission end of the ball joint 42 is rotatably connected to the back side of the rectangular rotating plate 41. The base of the ball joint 42 is installed on the frame. A ball joint knob 421 is provided at the end of the ball joint 42 away from the rectangular rotating plate 41. The ball joint 42 drives the rectangular rotating plate 41 to rotate to a suitable angle, and the ball joint knob 421 is tightened to fix it.

[0036] In this embodiment, the square grooves are excavated in a stepped depth, and the depths of the four square grooves decrease in a clockwise direction, so that the devices do not interfere with each other during operation.

[0037] Telescopic mechanisms (5) are respectively provided at the four corners of the rectangular rotating plate 41, and the ends of the telescopic mechanisms (5) are connected to right-angle sleeves 54. A protective groove 547 is provided on one side of the right-angle sleeve where the calibration plate 546 is placed, and the top of the protective groove 547 is set to be rounded. In this embodiment, the protective groove 547 is made of rubber material.

[0038] The telescopic mechanism 5 includes a gear 51, a rack 52 and a scissor mechanism 53. The rack 52 is respectively embedded in the four square grooves 45. The gear 51 is embedded in the circular groove 44 and meshes with the rack 52 one by one. The end of the rack 52 away from the ball joint 42 is slidably connected to a side of the right-angle sleeve 54. The gear 51 is controlled by a knob 511. The gear 51 is used to rotate the transmission rack 52 to adjust the position of the telescopic mechanism. A locking device 512 is provided on one side of the gear 51. When the telescopic mechanism 5 is in a suitable position, the locking device 512 locks the gear and fixes the telescopic mechanism 5. The locking device 512 includes internal thread holes provided at the four corner ends of the rectangular rotating plate 41 and fixing screws 513 matching the internal thread holes. When the telescopic mechanism 5 is in a suitable position, the fixing screws 513 are screwed into the circular groove 44 and locked tightly against the side of the gear 51.

[0039] A first limiting groove 541 is provided on one side of the right-angle sleeve 54, and a protrusion 521 is provided on one end of the rack 52 away from the ball joint 42, and the first limiting groove 541 is slidably connected to the protrusion 521; a second limiting groove 542 is provided on the other side of the right-angle sleeve 54, one end point of the moving end of the scissor mechanism 53 is rotatably connected to a fixed limiting column 543 provided on the right-angle sleeve 54, and the other end point is rotatably connected to a movable limiting column 544, and the movable limiting column 544 is slidably connected to the second limiting groove 542, and the stationary end of the scissor mechanism 53 is rotatably connected to a connecting column 545 on the rectangular rotating plate 41.

[0040] The scissor mechanism 53 includes a left shear arm 531 and a right shear arm 532. The left shear arm 531 includes at least one movable porous scissor blade 533 and one fixed porous scissor blade 534. The movable porous scissor blade 533 and the fixed porous scissor blade 534 are rotationally connected in sequence through axial holes. The right shear arm 532 and the left shear arm 531 have the same structure, and the fixed porous scissor blades are axially connected to each other in a scissor shape.

[0041] In this embodiment, the movable multi-hole scissor blade 533 includes a four-hole scissor blade and a five-hole scissor blade, and the fixed multi-hole scissor blade is a six-hole scissor blade. The bottom axial hole of the four-hole scissor blade is rotatably connected to the top axial hole of the five-hole scissor blade, and the bottom axial hole of the five-hole scissor blade is rotatably connected to the top axial hole of the six-hole scissor blade. The axial connection position of the left shear arm and the right shear arm is located at the fourth axial hole from the top axial hole of the six-hole scissor blade.

[0042] The present invention also proposes a combined calibration method for a large field of view camera combined calibration device:

[0043] Step 1: 4 sets of rotating components 4 and telescopic mechanisms 5 are arranged on the frame 1, with two sets arranged in each row, and two rows in total, so that no two sets affect each other;

[0044] Step 2: Adjust the direction of the rectangular rotating plate 41 through the ball joint 42, adjust the length of the telescopic mechanism 5 according to the size of the calibration plate 546, and respectively set corresponding calibration plates 546 on the right-angle sleeves 54 at the ends of the four groups of telescopic mechanisms 5;

[0045] Step 3: Tighten the ball joint knob 421 and the locking device 512 to fix the current position of the calibration plate;

[0046] Step 4: Start combined calibration.

[0047] The detailed steps are as follows: 4 groups of rotating components 4 and telescopic mechanisms 5 are set on the frame 1, with two groups in each row, and two rows in total, without affecting each other; take out 1 to 4 calibration plates, and respectively insert the protective grooves 547 on the right-angle sleeve 54 into the four corners of the calibration plate in turn, and the right-angle sleeve 54 adjusts the angle by moving the limit column 544 to cooperate with the rotating component 4 to adjust the fixed angle of the calibration plate. After the calibration plate is installed, the rack 52 is driven by the knob 511 on the rotating gear 51 to drive the scissor mechanism 53 to retract and retract, and then the position of the calibration plate is adjusted. When the position of the calibration plate meets the requirements of the photographic operation, tighten the ball joint knob 421 and the locking device 512, combine the calibration and start the photographic work.

[0048] In the description of the present invention, the positions or positional relationships indicated by terms such as "top", "bottom", "upper", "lower", etc. are based on the positions or positional relationships shown in the accompanying drawings. These terms are only used to facilitate description and simplify the explanation, and do not indicate or imply that the device or element must have a specific orientation or be constructed and operated according to a specific orientation, and therefore should not be regarded as limiting the scope of protection of the present invention.

[0049] The above description of the embodiments enables professionals and technicians in the field to implement or use the present invention. Various modifications to the embodiments will be apparent to professionals and technicians. The general principles of the present invention can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention should not be limited to the embodiments shown herein, but should cover the widest range consistent with the principles and novel features disclosed in the present invention.

Claims

1. A large field of view camera combination calibration device, comprising a frame (1), characterized in that: The device also includes a rotating assembly (4) and a telescopic mechanism (5); The rotating assembly (4) comprises a rectangular rotating plate (41) and a ball joint (42); four circular grooves (44) are provided at equidistant positions in the corner end of the back side of the rectangular rotating plate (41); four square grooves (45) are provided on both sides of the circular groove (44) parallel to the diagonal direction of the rectangular rotating plate (41); the depths of the two intersecting square grooves (45) are different; the transmission end of the ball joint (42) is rotatably connected to the back side of the rectangular rotating plate (41); and the base of the ball joint (42) is installed on the frame; The four corners of the rectangular rotating plate (41) are respectively provided with telescopic mechanisms (5), and the ends of the telescopic mechanisms (5) are connected to right-angle sleeves (54); The telescopic mechanism (5) comprises a gear (51), a rack (52) and a scissor mechanism (53), wherein the racks (52) are respectively embedded in four square grooves (45), the gears (51) are embedded in circular grooves (44) and mesh with the racks (52) one by one, one end of the rack (52) away from the ball joint (42) is slidably connected to a side surface of a right-angle sleeve (54), the stationary end of the scissor mechanism (53) is rotatably connected to the rectangular rotating plate (41), and the movable end thereof comprises two end points, one end point is rotatably connected to the other side surface of the right-angle sleeve (54), and the other end point is slidably connected to the other side surface of the right-angle sleeve (54).

2. The large field of view camera combination calibration device according to claim 1, characterized in that: The frame (1) comprises a plurality of main beams (2) arranged at equal intervals along the length direction, and a plurality of secondary beams (3) arranged at equal intervals along the width direction, wherein the secondary beams (3) intersect and are perpendicular to the main beams (2), a plurality of convex platforms (43) are fixed on the upper surface of the frame (1), the base of the ball joint (42) is mounted on the convex platform (43), and a plurality of groups of rotating components (4) and telescopic mechanisms (5) are mounted on the frame (1) without affecting each other.

3. The large field of view camera combination calibration device according to claim 1, characterized in that: The gear (51) is controlled by a knob (511), and the gear (51) is used to rotate the transmission rack (52) to adjust the position of the telescopic mechanism (5). A locking device (512) is provided on one side of the gear (51). When the telescopic mechanism (5) is telescoped to a suitable position, the locking device (512) locks the gear and fixes the telescopic mechanism (5).

4. The large field of view camera combination calibration device according to claim 3, characterized in that: The locking device (512) comprises internal thread holes arranged at the four corner ends of the rectangular rotating plate (41) and fixing screws (513) matching the internal thread holes. When the telescopic mechanism (5) is telescoped to a suitable position, the fixing screws (513) are screwed into the circular groove (44) and tightly locked against the side of the gear (51).

5. The large field of view camera combination calibration device according to claim 1, characterized in that: A ball joint knob (421) is provided at one end of the ball joint (42) away from the rectangular rotating plate (41). The ball joint (42) drives the rectangular rotating plate (41) to rotate to a suitable angle, and the ball joint knob (421) is tightened to fix it.

6. The large field of view camera combination calibration device according to claim 1, characterized in that: A first limiting groove (541) is provided on one side of the right-angle sleeve (54), and a second limiting groove (542) is provided on the other side of the right-angle sleeve (54); a protrusion (521) is provided at one end of the rack (52) away from the ball joint (42), and the protrusion (521) is slidably connected in the first limiting groove (541); the stationary end of the scissor mechanism (53) is rotatably connected to a connecting column arranged on the side of the rectangular rotating plate (41), one end point of the movable end of the scissor mechanism (53) is rotatably connected to a fixed limiting column (543) arranged on the right-angle sleeve (54), and a movable limiting column (544) is provided on the other end point, and the movable limiting column (544) is slidably connected in the second limiting groove (542).

7. The large field of view camera combination calibration device according to claim 1 or 6, characterized in that: The scissor mechanism (53) comprises a left shear arm (531) and a right shear arm (532); the left shear arm (531) comprises at least one movable porous scissor blade (533) and one fixed porous scissor blade (534); the movable porous scissor blade (533) and the fixed porous scissor blade (534) are rotatably connected in sequence via an axial hole; the right shear arm (532) and the left shear arm (531) have the same structure; and the fixed porous scissor blades are axially connected to each other in a scissor-like shape.

8. The large field of view camera combination calibration device according to claim 1, characterized in that: A protective groove (547) is provided on one side of the right-angle sleeve on which the calibration plate (546) is placed. The top of the protective groove (547) is configured as a rounded corner. The protective groove (547) is made of rubber material.

9. A combined calibration method based on the combined calibration device for large field of view cameras according to any one of claims 1 to 8, characterized in that: The steps include: Step 1: 4 sets of rotating components (4) and telescopic mechanisms (5) are arranged on the frame (1), with two sets arranged in each row, and two rows in total, so that no two sets affect each other; Step 2: Adjust the direction of the rectangular rotating plate (41) through the ball joint (42), adjust the length of the telescopic mechanism (5) according to the size of the calibration plate (546), and respectively set corresponding calibration plates (546) on the right-angle sleeves (54) at the ends of the four sets of telescopic mechanisms (5); Step 3: Tighten the ball joint knob (421) and the locking device (512) to fix the current position of the calibration plate; Step 4: Start combined calibration.

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