An adjustable calibration target for a 3D camera

Abstract

The utility model discloses a kind of adjustable calibration targets for 3D camera, including base, center column is installed on base, rotatable rotary table is installed on center column, the middle part of rotary table is installed with mounting seat, rotatable calibration target is installed on mounting seat, and calibration target is provided with multiple groups of calibration characteristic points in geometric array on it.The beneficial effects of the utility model are: by setting rotatable first rotating rod and second rotating rod, the angle adjustment of calibration target in three-dimensional space can be realized, the flexible adjustment of calibration target in space pose is realized, the quick locking of first rotating rod and second rotating rod can be realized by setting first locking mechanism and second locking mechanism cooperation, the fixation of calibration target position is facilitated, and the subsequent calibration accuracy and calibration efficiency are improved.

Description

Technical Field

[0001] This utility model relates to the field of 3D camera calibration target technology, and in particular to an adjustable calibration target for 3D cameras. Background Technology

[0002] A 3D camera calibration target is a physical target object specifically designed and manufactured for calibrating, testing, and validating the performance of 3D cameras (depth cameras). Unlike planar calibration boards (such as checkerboards) used for traditional 2D cameras, 3D camera targets typically have a defined three-dimensional geometry and known spatial dimensions to accurately assess the accuracy of the depth information acquired by the camera. 3D camera targets are a key tool for ensuring the accuracy and reliability of 3D camera measurement data. It is a physical reference with a precisely known three-dimensional geometry and specific surface properties, its core purpose being to calibrate camera parameters (especially depth parameters) and validate various performance indicators of the camera (accuracy, resolution, etc.). Choosing a suitable target is crucial to fully realizing the potential of a 3D camera. High-quality 3D camera targets are indispensable in fields such as industrial inspection, robot navigation, 3D reconstruction, and virtual reality / augmented reality.

[0003] Some existing 3D camera targets typically use fixed three-dimensional geometric structures. Fixed targets are difficult to adjust in terms of spatial angle during calibration, and the adjustment process is cumbersome for staff, which limits the improvement of calibration accuracy and efficiency, making them unable to meet the needs of different calibration scenarios. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings of existing 3D camera targets, which typically adopt fixed three-dimensional geometric structures. Fixed targets are difficult to adjust spatial angles during calibration, and the adjustment process is cumbersome for operators, limiting the improvement of calibration accuracy and efficiency and making them unable to adapt to different calibration scenarios. This invention provides an adjustable calibration target for 3D cameras.

[0005] The purpose of this utility model is achieved through the following technical solution: an adjustable calibration target for a 3D camera, including a base, a central column mounted on the base, a rotatable turntable mounted on the central column, a mounting seat mounted in the middle of the turntable, a rotatable calibration target mounted on the mounting seat, and multiple sets of calibration feature points arranged in a geometric array on the calibration target. Both the turntable and the calibration target are disc-shaped, and the sides of the turntable and the calibration target are respectively provided with a first scale line and a second scale line. The side of the central column is equipped with a first indicator needle corresponding to the first scale line, and the side of the mounting base is equipped with a second indicator needle corresponding to the second scale line. A rotatable first rotating rod is installed at the top of the central column. A turntable is installed on the first rotating rod. A first locking mechanism for locking the first rotating rod is installed between the first rotating rod and the central column. A rotatable second rotating rod is installed on the mounting base. One end of the second rotating rod passes through the mounting base and is connected to one side of the calibration target. A second locking mechanism for locking the second rotating rod is installed between the mounting base and the second rotating rod.

[0006] By setting up rotatable first and second rotating rods, the angle of the calibration target in three-dimensional space can be adjusted, enabling flexible adjustment of the target's spatial posture. Simultaneously, the first scale line on the turntable, in conjunction with the first indicator needle, facilitates adjustment of the target's rotation angle on the turntable. Similarly, the second scale line on the target, in conjunction with the second indicator needle, facilitates adjustment of the target's rotation angle on the second rotating rod, thus achieving precise control of the target's rotation angle in three-dimensional space. Furthermore, the first and second scale lines are easily observable by the operator. The combination of a first and second locking mechanism allows for rapid locking of the first and second rotating rods, facilitating the fixation of the target's position and improving subsequent calibration accuracy and efficiency.

[0007] A further technical solution is to install a telescopic rod on the central column, with a first rotating rod rotatably mounted on the top of the telescopic rod and a first indicator needle mounted on one side of the upper part of the telescopic rod. The telescopic rod enables the height adjustment of the calibration target, meeting different requirements for the target height during the calibration process and improving the applicability of the device.

[0008] A further technical solution is that the first locking mechanism includes a first locking thread on the outside of the first rotating rod, a first locking nut installed on the first locking thread, and the end face of the first locking nut being frictionally locked with the telescopic rod.

[0009] A further technical solution is that the second locking mechanism includes a second locking thread formed on the outside of the second rotating rod, a second locking nut installed on the second locking thread, and the end face of the second locking nut being frictionally locked with the mounting base. The first locking nut and the second locking nut are wing-shaped compression nuts. By setting a first locking nut to engage with a first locking thread on the outside of the first rotating rod, the end face of the first locking nut can be rubbed and locked with the telescopic rod by rotating the first locking nut, thereby locking the first rotating rod. By setting a second locking nut to engage with a second locking thread on the outside of the second rotating rod, the end face of the second locking nut can be rubbed and locked with the mounting base by rotating the second locking nut, thereby locking the second rotating rod. The operator can lock the rotation angle of the calibration target simply by operating the first and second locking nuts, which improves the convenience of operation, reduces the workload of the operator, and improves the overall calibration efficiency.

[0010] A further technical solution involves installing a limit block inside the central column, and a limit groove on the telescopic rod that slides in conjunction with the limit block. By setting the limit block and the limit groove to cooperate, the telescopic rod can be limited and guided during extension and retraction, preventing relative displacement between the telescopic rod and the central column that could cause deviations in the turntable angle and ensuring the stability of the turntable during the extension and retraction of the telescopic rod.

[0011] A further technical solution involves a threaded hole on the central column, through which a set screw is threadedly connected. One end of the set screw passes through the threaded hole and engages with the side of the telescopic rod for friction locking. By using a set screw to engage with the telescopic rod through the threaded hole for friction locking, the telescopic rod can be easily locked during extension and retraction, improving operational convenience.

[0012] A further technical solution is that the calibration target has a double-layer composite structure, including a rigid substrate made of metal material and a feature layer attached to the surface of the rigid substrate. The feature layer is a high-contrast non-reflective material, such as low-reflection glass. By setting the feature layer to be a high-contrast non-reflective material, the color of the calibration feature point can form a high contrast with the feature layer. For example, white circular dots can be printed on a black background, or black circular dots can be printed on a white background, to ensure that the 3D camera can clearly and accurately identify and extract the center coordinates of the calibration feature point.

[0013] A further technical solution is to have a connected tool compartment and a counterweight compartment inside the base. The counterweight compartment contains a counterweight block, and a cover plate is installed on the top of the tool compartment. The tool compartment is made of steel, and a magnetic strip corresponding to the tool compartment is installed on the cover plate. By setting up the tool compartment to hold tools, and setting up the counterweight compartment and counterweight block to increase the weight of the base, the overall stability of the equipment is improved in different environments.

[0014] A further technical solution is to install multiple sets of threaded sleeves at the bottom of the base, with leveling feet threaded onto the lower part of the threaded sleeves. Anti-slip pads are installed at the bottom of the leveling feet. By setting the threaded sleeves and leveling feet, the length of the leveling feet can be easily adjusted for leveling in different environments. The anti-slip pads are set to increase the friction of the leveling feet and further improve their stability.

[0015] This invention has the following advantages: By setting a rotatable first and second rotating rod, the angle of the calibration target in three-dimensional space can be adjusted, enabling flexible adjustment of the target's spatial posture. Simultaneously, the first scale line on the turntable, in conjunction with the first indicator needle, facilitates adjustment of the target's rotation angle on the turntable. Similarly, the second scale line on the target, in conjunction with the second indicator needle, facilitates adjustment of the target's rotation angle on the second rotating rod, thereby achieving precise control of the target's rotation angle in three-dimensional space. Furthermore, the first and second scale lines are easily observable by the operator. Finally, the first and second locking mechanisms work together to quickly lock the first and second rotating rods, facilitating the fixation of the target's position and improving subsequent calibration accuracy and efficiency. Attached Figure Description

[0016] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a partial cross-sectional view of the front structure of this utility model; Figure 3 This is a partial cross-sectional view of the front structure of this utility model; In the diagram: 1. Base; 2. Central column; 3. Turntable; 4. Mounting base; 5. Calibration target; 6. First scale line; 7. First indicator needle; 8. Second scale line; 9. Second indicator needle; 10. First rotating rod; 11. Second rotating rod; 12. Telescopic rod; 13. Set screw; 14. Tool compartment; 15. Cover plate; 16. Magnetic strip; 17. Threaded sleeve; 18. Leveling foot; 19. Anti-slip pad; 20. First locking nut; 21. Limiting block; 22. Limiting groove; 23. Second locking nut; 24. Counterweight compartment; 25. Counterweight block. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can typically be arranged and designed in various different configurations.

[0018] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0019] It should be noted that, where there is no conflict, the embodiments and features in the embodiments of this utility model can be combined with each other.

[0020] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0021] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this utility model is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only used for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first," "second," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0022] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0023] like Figures 1-3 As shown, an adjustable calibration target for a 3D camera includes a base 1, a central column 2 mounted on the base 1, a rotatable turntable 3 mounted on the central column 2, a mounting base 4 mounted in the middle of the turntable 3, and a rotatable calibration target 5 mounted on the mounting base 4. The calibration target 5 is provided with multiple sets of calibration feature points arranged in a geometric array. Both the turntable 3 and the calibration target 5 are disc-shaped, and the turntable 3 and the calibration target 5 are respectively provided with a first scale line 6 and a second scale line 8 on their sides. The side of the central column 2 is equipped with a first indicator needle 7 corresponding to the first scale line 6, and the side of the mounting base 4 is equipped with a second indicator needle 9 corresponding to the second scale line 8. The first scale line 6 and the second scale line 8 are angle scale lines. A rotatable first rotating rod 10 is installed at the top of the central column 2. The turntable 3 is installed on the first rotating rod 10. A first locking mechanism for locking the first rotating rod 10 is installed between the first rotating rod 10 and the central column 2. A rotatable second rotating rod 11 is installed on the mounting base 4. One end of the second rotating rod 11 passes through the mounting base 4 and is connected to one side of the calibration target 5. A second locking mechanism for locking the second rotating rod 11 is installed between the mounting base 4 and the second rotating rod 11.

[0024] By setting a rotatable first rotating rod 10 and a second rotating rod 11, the angle of the calibration target 5 in three-dimensional space can be adjusted, enabling flexible adjustment of the spatial posture of the calibration target 5. At the same time, the first scale line 6 on the turntable 3 cooperates with the first indicator needle 7 to facilitate the adjustment of the rotation angle of the calibration target 5 on the turntable 3. The second scale line 8 on the calibration target 5 cooperates with the second indicator needle 9 to facilitate the adjustment of the rotation angle of the calibration target 5 on the second rotating rod 11, thereby achieving precise control of the rotation angle of the calibration target 5 in three-dimensional space. In addition, the first scale line 6 and the second scale line 8 are also convenient for the staff to observe directly. Furthermore, the first locking mechanism and the second locking mechanism cooperate to achieve quick locking of the first rotating rod 10 and the second rotating rod 11, which facilitates the fixation of the position of the calibration target 5 and improves the subsequent calibration accuracy and calibration efficiency.

[0025] A telescopic rod 12 is installed on the central column 2. The first rotating rod 10 is rotatably installed on the top of the telescopic rod 12, and the first indicator needle 7 is installed on one side of the upper part of the telescopic rod 12. The telescopic rod 12 can realize the height adjustment of the calibration target 5, meet the different height requirements of the calibration target 5 during the calibration process, and improve the applicability of the device.

[0026] The first locking mechanism includes a first locking thread on the outside of the first rotating rod 10, and a first locking nut 20 is installed on the first locking thread. The end face of the first locking nut 20 is frictionally locked with the telescopic rod 12.

[0027] The second locking mechanism includes a second locking thread located on the outside of the second rotating rod 11. A second locking nut 23 is installed on the second locking thread. The end face of the second locking nut 23 is frictionally locked to the mounting base 4. The first locking nut 20 and the second locking nut 23 are wing-shaped compression nuts. By setting the first locking nut 20 to engage with the first locking thread on the outside of the first rotating rod 10, the end face of the first locking nut 20 can be rubbed and locked with the telescopic rod 12 by rotating the first locking nut 20, thereby locking the first rotating rod 10. By setting the second locking nut 23 to engage with the second locking thread on the outside of the second rotating rod 11, the end face of the second locking nut 23 can be rubbed and locked with the mounting base 4 by rotating the second locking nut 23, thereby locking the second rotating rod 11. The operator can lock the rotation angle of the calibration target 5 by simply rotating the first locking nut 20 and the second locking nut 23, which improves the convenience of operation, reduces the workload of the operator, and improves the overall calibration efficiency.

[0028] A limiting block 21 is provided inside the central column 2, and a limiting groove 22 that is slidably connected to the limiting block 21 is installed on the telescopic rod 12. By setting the limiting block 21 and the limiting groove 22 to cooperate, the telescopic rod 12 can be limited and guided during extension and retraction, so as to avoid relative displacement between the telescopic rod 12 and the central column 2 during extension and retraction, which would cause the turntable 3 to deviate in angle and ensure the stability of the turntable 3 during extension and retraction of the telescopic rod 12.

[0029] The central column 2 has a threaded hole, and a set screw 13 is threadedly connected to the central column 2 through the threaded hole. One end of the set screw 13 passes through the threaded hole and is frictionally locked to the side of the telescopic rod 12. By setting the set screw 13 to pass through the threaded hole to frictionally lock the telescopic rod 12, it is easy to lock the telescopic rod 12 when it is extended or retracted, thus improving the convenience of operation.

[0030] The calibration target 5 has a double-layer composite structure, including a rigid substrate made of metal and a feature layer attached to the surface of the rigid substrate. The feature layer is a high-contrast non-reflective material, such as low-reflection glass. By setting the feature layer to be a high-contrast non-reflective material, the color of the calibration feature point can form a high contrast with the feature layer. For example, white circular dots can be printed on a black background, or black circular dots can be printed on a white background, to ensure that the 3D camera can clearly and accurately identify and extract the center coordinates of the calibration feature point.

[0031] The base 1 has a connected tool compartment 14 and a counterweight compartment 24. The counterweight compartment 24 contains a counterweight 25. The tool compartment 14 is covered with a cover plate 15. The tool compartment 14 is made of steel. The cover plate 15 is equipped with a magnetic strip 16 corresponding to the tool compartment 14. The tool compartment 14 is used to place tools. The counterweight compartment 24 and the counterweight 25 are used to increase the weight of the base 1, thereby improving the overall stability of the equipment in different environments.

[0032] Multiple sets of threaded sleeves 17 are installed at the bottom of the base 1. The threaded sleeves 17 are threaded with leveling feet 18 at the bottom. The bottom of the leveling feet 18 is equipped with anti-slip pads 19. By setting the threaded sleeves 17 and leveling feet 18, the length of the leveling feet 18 can be easily adjusted for leveling in different environments. The anti-slip pads 19 are set to improve the friction of the leveling feet 18 and further improve the stability of the leveling feet 18.

[0033] The working process of this utility model is as follows: When using the calibration target, firstly, adjust each threaded sleeve 17 and leveling foot 18 according to different environments to achieve leveling. After leveling, rotate the turntable 3 by loosening the first locking nut 20 on the first rotating rod 10. Observe the first scale line 6 on the side of the turntable 3 through the first indicator needle 7 to adjust the turntable 3 to the required angle. Then, tighten the first locking nut 20 to lock the first rotating rod 10 and the turntable 3. Next, rotate the calibration target 5 by loosening the second locking nut 23 on the second rotating rod 11. Observe the second scale line 8 on the side of the calibration target 5 through the second indicator needle 9 to adjust the calibration target 5 to the required angle. Then, tighten the second locking nut 23 to lock the second rotating rod 11 and the calibration target 5. This completes the multi-dimensional angle adjustment of the calibration target 5. Finally, adjust the height of the calibration target 5 by adjusting the extension height of the telescopic rod 12 through the set screw 13.

[0034] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An adjustable calibration target for a 3D camera, comprising a base (1), characterized in that: A central column (2) is installed on the base (1), a rotatable turntable (3) is installed on the central column (2), a mounting base (4) is installed in the middle of the turntable (3), a rotatable calibration target (5) is installed on the mounting base (4), and multiple sets of calibration feature points arranged in a geometric array are provided on the calibration target (5). The turntable (3) and the calibration target (5) are both disc-shaped, and the turntable (3) and the calibration target (5) are respectively provided with a first scale line (6) and a second scale line (8) on their sides. The side of the central column (2) is equipped with a first indicator needle (7) corresponding to the first scale line (6), and the side of the mounting base (4) is equipped with a second indicator needle (9) corresponding to the second scale line (8). The top of the central column (2) is equipped with a rotatable first rotating rod (10), the turntable (3) is mounted on the first rotating rod (10), a first locking mechanism for locking the first rotating rod (10) is installed between the first rotating rod (10) and the central column (2), a rotatable second rotating rod (11) is mounted on the mounting base (4), one end of the second rotating rod (11) passes through the mounting base (4) and is connected to one side of the calibration target (5), a second locking mechanism for locking the second rotating rod (11) is installed between the mounting base (4) and the second rotating rod (11).

2. The adjustable calibration target for a 3D camera according to claim 1, characterized in that: The central column (2) is equipped with a telescopic rod (12), the first rotating rod (10) is rotatably mounted on the top of the telescopic rod (12), and the first indicator needle (7) is mounted on one side of the upper part of the telescopic rod (12).

3. An adjustable calibration target for a 3D camera according to claim 2, characterized in that: The first locking mechanism includes a first locking thread on the outside of the first rotating rod (10), and a first locking nut (20) is installed on the first locking thread. The end face of the first locking nut (20) is frictionally locked with the telescopic rod (12).

4. An adjustable calibration target for a 3D camera according to claim 3, characterized in that: The second locking mechanism includes a second locking thread on the outside of the second rotating rod (11), and a second locking nut (23) is installed on the second locking thread. The end face of the second locking nut (23) is frictionally locked with the mounting base (4).

5. An adjustable calibration target for a 3D camera according to claim 2, characterized in that: A limiting block (21) is provided inside the central column (2), and a limiting groove (22) that is slidably connected to the limiting block (21) is installed on the telescopic rod (12).

6. An adjustable calibration target for a 3D camera according to claim 5, characterized in that: The central column (2) has a threaded hole, and the central column (2) is threadedly connected to a set screw (13) through the threaded hole. One end of the set screw (13) passes through the threaded hole and is rubbed and locked to the side of the telescopic rod (12).

7. An adjustable calibration target for a 3D camera according to claim 1, characterized in that: The calibration target (5) is a double-layer composite structure, including a rigid substrate made of metal material and a feature layer attached to the surface of the rigid substrate. The feature layer is a high-contrast non-reflective material.

8. An adjustable calibration target for a 3D camera according to claim 1, characterized in that: The base (1) is provided with a connected tool compartment (14) and a counterweight compartment (24). A counterweight block (25) is placed in the counterweight compartment (24). A cover plate (15) is installed on the upper part of the tool compartment (14). The tool compartment (14) is made of steel. A magnetic strip (16) corresponding to the tool compartment (14) is installed on the cover plate (15).

9. An adjustable calibration target for a 3D camera according to claim 1, characterized in that: The base (1) has multiple sets of threaded sleeves (17) installed at the bottom. The threaded sleeves (17) have leveling feet (18) threaded on the lower part. The leveling feet (18) have anti-slip pads (19) installed at the bottom.

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