A device for collecting a three-dimensional workpiece point cloud

Abstract

The application discloses a kind of acquisition devices of three-dimensional workpiece point cloud, it is related to three-dimensional measurement technical field, including base, first guide rail assembly, first ball screw pair, second ball screw pair, third ball screw pair, gantry, second guide rail assembly, connecting plate, measurement mounting plate, rotating mechanism and point cloud acquisition measurement component.In the application, gantry can realize XYZ three-axis movement, and cooperate with the rotatable setting of measurement mounting plate, so that point cloud acquisition measurement component can have the movement of multiple degrees of freedom, while cooperating with rotating mechanism to drive the workpiece to be measured to rotate, so that point cloud acquisition measurement component can quickly reach each part of workpiece for collection, without manually turning over workpiece, greatly save the collection time, improve the collection efficiency;At the same time, avoid the displacement error caused by manually turning over workpiece, ensure that the point cloud data collected can accurately reflect the real shape and size of workpiece.

Description

Technical Field

[0001] This invention relates to the field of three-dimensional measurement technology, and in particular to a device for acquiring three-dimensional workpiece point clouds. Background Technology

[0002] In the field of 3D measurement, it is crucial to accurately and efficiently acquire point cloud data of 3D workpieces.

[0003] Traditional 3D workpiece point cloud acquisition devices often only possess three translational degrees of freedom (X, Y, Z), which means the acquisition device's orientation remains fixed. This limitation is particularly pronounced in actual acquisition processes. Especially for 3D workpieces with complex shapes, such as those with sides, backs, concave surfaces, internal holes, and bottom features, the acquisition device cannot directly align with these areas. To complete comprehensive acquisition, operators must manually rotate the workpiece. Manual rotation is not only cumbersome and inefficient but also inevitably introduces object displacement errors. These errors are amplified during subsequent point cloud stitching, significantly increasing the workload. Because a considerable amount of time and effort is required to adjust and match the point cloud data with deviations caused by displacement, it also leads to a loss of accuracy. The final acquired point cloud data may not accurately reflect the true shape and size of the workpiece. For industrial production and research fields with extremely high precision requirements, such as aerospace component manufacturing and precision mold processing, this loss of accuracy can have serious consequences, even leading to product scrapping or inaccurate research results. Summary of the Invention

[0004] The purpose of this invention is to provide a three-dimensional workpiece point cloud acquisition device to solve the above-mentioned technical problems.

[0005] The technical solution adopted in this invention is as follows: A three-dimensional workpiece point cloud acquisition device includes a base, a first guide rail assembly, a first ball screw pair, a second ball screw pair, a third ball screw pair, a gantry frame, a second guide rail assembly, a connecting plate, a measuring mounting plate, a rotating mechanism, and a point cloud acquisition and measurement component. Two first guide rail assemblies are disposed at both ends of the base, and the first ball screw pairs are disposed within the first guide rail assemblies. The gantry frame is disposed at the upper end of the first guide rail assemblies, and two second ball screw pairs are disposed on the gantry frame. Second guide rail assemblies are disposed on the two second ball screw pairs, and the third ball screw pair is disposed within the second guide rail assemblies. The connecting plate is disposed at the lower end of the second guide rail assemblies, and the measuring mounting plate is rotatably disposed on the connecting plate. The point cloud acquisition and measurement component is disposed on the measuring mounting plate. The rotating mechanism is disposed at the upper end of the base and is used to place the workpiece to be measured.

[0006] Preferably, the first guide rail assembly includes a first guide rail and a first slider disposed on the first guide rail, and the gantry frame is connected to the two first sliders; The first ball screw assembly includes a first screw and a first nut disposed on the first screw. The first screw is rotatably disposed within the first guide rail. The first nut is connected to the first slider. The first motor is disposed at one end of the first guide rail and is connected to the first screw.

[0007] Preferably, the second ball screw assembly includes a second screw and a second nut disposed on the second screw. The two ends of the second screw are connected to the gantry frame through screw support seats. The upper end of the gantry frame is provided with a second motor, which is connected to the second screw.

[0008] As a further preferred embodiment, the second guide rail assembly includes a second guide rail and a second slider disposed on the second guide rail, with both ends of the second guide rail connected to two second nuts, and the connecting plate connected to the lower end of the second slider.

[0009] As a further preferred embodiment, the third ball screw assembly includes a third screw and a third nut disposed on the third screw. The third screw is disposed within the second guide rail, and the third nut is connected to the second slider. A third motor is disposed at one end of the second guide rail, and the third motor is connected to the third screw.

[0010] Preferably, the point cloud acquisition and measurement component includes a lidar and a structured light camera. The lidar is mounted on the measurement mounting plate, and the two structured light cameras are distributed on both sides of the lidar. A fourth motor is provided on one side of the connecting plate, and the output end of the fourth motor is connected to the measurement mounting plate.

[0011] As a further preferred embodiment, the angle between the axis of the structured light camera and the axis of the lidar is 15°.

[0012] Preferably, the rotating mechanism includes a rotating disk, a support disk, a support rod, and a fifth motor. The fifth motor is installed inside the base, and the rotating disk is installed at the upper end of the base. The output end of the fifth motor is connected to the rotating disk. The support rod is installed at the upper end of the rotating disk, and the support disk is installed at the upper end of the support rod. The upper end of the support disk is used to place the workpiece to be measured.

[0013] As a further preferred option, the support plate is made of transparent silicon carbide.

[0014] The above technical solution has the following advantages or beneficial effects: (1) In this invention, the gantry can realize XYZ three-axis movement, and with the rotatable setting of the measurement mounting plate, the point cloud acquisition and measurement component can have multiple degrees of freedom of movement. At the same time, with the rotation mechanism, the workpiece to be measured is rotated, so that the point cloud acquisition and measurement component can quickly reach various parts of the workpiece for acquisition without manually flipping the workpiece, which greatly saves acquisition time and improves acquisition efficiency. At the same time, it avoids the displacement error caused by manually flipping the workpiece, ensuring that the acquired point cloud data can accurately reflect the real shape and size of the workpiece.

[0015] (2) In this invention, by setting each ball screw pair, the movement of each component can be made more precise, reducing motion error. And by using the combination of lidar and structured light camera, more comprehensive and accurate point cloud data can be obtained.

[0016] (3) In this invention, by setting the angle between the structured light camera axis and the lidar axis at 15°, the lidar and structured light camera work together better, which further improves the accuracy of data acquisition. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the three-dimensional workpiece point cloud acquisition device in this invention when measuring the upper surface; Figure 2 This is a schematic diagram of the structure of the three-dimensional workpiece point cloud acquisition device in this invention when measuring the side surface; Figure 3 This is a schematic diagram of the structure of the three-dimensional workpiece point cloud acquisition device in this invention when measuring the bottom surface.

[0018] In the diagram: 1. Base; 2. First guide rail assembly; 201. First guide rail; 202. First slider; 3. First ball screw pair; 301. First lead screw; 302. First nut; 4. Second ball screw pair; 401. Second lead screw; 402. Second nut; 5. Third ball screw pair; 501. Third lead screw; 502. Third nut; 6. Gantry frame; 7. Second guide rail assembly; 701. Second guide rail; 702. Second slider; 8. Connecting plate; 9. Measuring mounting plate; 10. Rotating mechanism; 1001. Rotating disk; 1002. Support disk; 1003. Support rod; 11. Workpiece to be measured; 12. First motor; 13. Second motor; 14. Third motor; 15. LiDAR; 16. Structured light camera; 17. Fourth motor. Detailed Implementation

[0019] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] In the description of this invention, it should be noted that terms such as "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. They are used only for the convenience of describing this invention and for 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 invention. Furthermore, terms such as "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0021] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" 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 invention based on the specific circumstances.

[0022] Please see Figures 1 to 3As shown, a preferred embodiment is illustrated, illustrating a three-dimensional workpiece point cloud acquisition device, comprising a base 1, a first guide rail assembly 2, a first ball screw pair 3, a second ball screw pair 4, a third ball screw pair 5, a gantry frame 6, a second guide rail assembly 7, a connecting plate 8, a measuring mounting plate 9, a rotating mechanism 10, and a point cloud acquisition and measurement component. Two first guide rail assemblies 2 are disposed at both ends of the base 1, and a first ball screw pair 3 is disposed within each first guide rail assembly 2. A gantry frame 6 is disposed at the upper end of the first guide rail assembly 2, and two second ball screw pairs 4 are disposed on the gantry frame 6. A second guide rail assembly 7 is disposed on each of the two second ball screw pairs 4, and a third ball screw pair 5 is disposed within each second guide rail assembly 7. A connecting plate 8 is disposed at the lower end of the second guide rail assembly 7, and a measuring mounting plate 9 is rotatably disposed on the connecting plate 8. A point cloud acquisition and measurement component is disposed on the measuring mounting plate 9. A rotating mechanism 10 is disposed at the upper end of the base 1, and the rotating mechanism 10 is used to place the workpiece 11 to be measured. In this embodiment, the first guide rail assembly 2 and the internal first ball screw pair 3 provide stable and precise translational motion for the gantry 6, enabling the gantry 6 to move precisely along a specific direction on the base 1, thereby adjusting the horizontal position of the acquisition device. The second ball screw pair 4 provides guidance for the vertical movement of the second guide rail assembly 7, and the second guide rail assembly 7 and the third ball screw pair 5 enable the point cloud acquisition and measurement component to move horizontally, precisely adjusting its position. The rotatable design of the measurement mounting plate 9 allows for flexible adjustment of the angle of the point cloud acquisition and measurement component, aligning it with complex features such as the sides, back, concave surfaces, inner holes, and bottom of the workpiece for acquisition. This eliminates the need for manual workpiece flipping, significantly improving acquisition efficiency and avoiding object displacement errors caused by manual flipping, ensuring high accuracy of the acquired data.

[0023] Furthermore, as a preferred embodiment, the first guide rail assembly 2 includes a first guide rail 201 and a first slider 202 disposed on the first guide rail 201, and the gantry 6 is connected to the two first sliders 202. The first ball screw assembly 3 includes a first screw 301 and a first nut 302 mounted on the first screw 301. The first screw 301 is rotatably mounted within a first guide rail 201. The first nut 302 is connected to a first slider 202. A first motor 12 is mounted at one end of the first guide rail 201 and is connected to the first screw 301. In use, the first motor 12 drives the first screw 301 to rotate, which in turn causes the first nut 302 to move linearly, thereby moving the first slider 202 along the first guide rail 201. This allows for adjustment of the X-axis position of the gantry 6, and consequently, adjustment of the X-axis position of the point cloud acquisition and measurement component.

[0024] Furthermore, as a preferred embodiment, the second ball screw assembly 4 includes a second screw 401 and a second nut 402 disposed on the second screw 401. Both ends of the second screw 401 are connected to the gantry frame 6 via screw support seats. A second motor 13 is disposed at the upper end of the gantry frame 6 and is connected to the second screw 401. The second motor 13 can drive the second screw 401 to rotate, causing the second nut 402 to move the second guide rail assembly 7 up and down, thereby adjusting the Z-axis position of the point cloud acquisition and measurement assembly.

[0025] Furthermore, in a preferred embodiment, the second guide rail assembly 7 includes a second guide rail 701 and a second slider 702 disposed on the second guide rail 701. Both ends of the second guide rail 701 are connected to two second nuts 402, and the connecting plate 8 is connected to the lower end of the second slider 702. The third ball screw assembly 5 includes a third screw 501 and a third nut 502 disposed on the third screw 501. The third screw 501 is disposed within the second guide rail 701, and the third nut 502 is connected to the second slider 702. A third motor 14 is disposed at one end of the second guide rail 701 and is connected to the third screw 501. When the third motor 14 is working, it can drive the third screw 501 to rotate, thereby moving the third nut 502 to adjust the Y-axis position of the point cloud acquisition and measurement assembly.

[0026] Furthermore, as a preferred implementation, the point cloud acquisition and measurement component includes a lidar 15 and two structured light cameras 16. The lidar 15 is mounted on the measurement mounting plate 9, and the two structured light cameras 16 are distributed on both sides of the lidar 15. A fourth motor 17 is mounted on one side of the connecting plate 8, and the output of the fourth motor 17 is connected to the measurement mounting plate 9. The lidar 15 can quickly acquire the three-dimensional spatial information of an object, and has the characteristics of large measurement range and high accuracy, making it particularly suitable for rapid scanning of the overall shape of a workpiece. The structured light cameras 16, distributed on both sides of the lidar 15, can acquire detailed information about the surface of the object using the structured light principle, supplementing and refining the data acquired by the lidar 15. The two work together to acquire more comprehensive and accurate point cloud data. In use, the fourth motor 17 can drive the measurement mounting plate 9 to rotate, thereby adjusting the angles of the lidar 15 and the structured light cameras 16, further improving the flexibility of acquisition and enabling better alignment of different parts of the workpiece for acquisition.

[0027] Furthermore, as a preferred implementation, the angle between the axis of the structured light camera 16 and the axis of the lidar 15 is 15°. By setting this angle, the structured light camera 16 can acquire details of the blind area scanned by the lidar 15 from a suitable angle, thereby improving the integrity and accuracy of the point cloud data and providing more complete data support for subsequent 3D modeling and analysis.

[0028] Furthermore, in a preferred embodiment, the rotating mechanism 10 includes a rotating disk 1001, a support disk 1002, a support rod 1003, and a fifth motor. The fifth motor is housed inside the base 1, and the rotating disk 1001 is located at the upper end of the base 1. The output end of the fifth motor is connected to the rotating disk 1001. The support rod 1003 is located at the upper end of the rotating disk 1001, and the support disk 1002 is located at the upper end of the support rod 1003. The upper end of the support disk 1002 is used to place the workpiece 11 to be measured. In this embodiment, during use, the fifth motor can drive the rotating disk 1001 to rotate, thereby causing the support disk 1002 and the workpiece to rotate. This allows the workpiece 11 placed on the support disk 1002 to rotate 360°. Simultaneously, in conjunction with the translation and angle adjustment of the point cloud acquisition and measurement component, point cloud data can be acquired from multiple angles to obtain more comprehensive workpiece information.

[0029] Furthermore, as a preferred embodiment, the support plate 1002 is made of transparent silicon carbide material with a light transmittance of ≥92%. In use, the fourth motor 17 drives the measuring mounting plate 9 to rotate the lidar 15. Then, through the cooperation of the first guide rail assembly 2, the first ball screw pair 3, the second ball screw pair 4, the third ball screw pair 5, and the second guide rail assembly 7, the lidar 15 can enter the lower side of the support plate 1002 to collect the point cloud of the bottom of the workpiece. During this process, there is no need to flip the workpiece.

[0030] In this embodiment, the first motor 12, the second motor 13, the third motor 14, the fourth motor 17, and the fifth motor can be connected to an external PLC controller to facilitate the control of each motor's operation.

[0031] In this embodiment, a scale line is provided on the side wall of the first guide rail 201 to detect the position of the first nut 302. If the two first nuts 302 are not on the same scale line, it indicates that there is a displacement difference between the two first nuts 302, and the position of the first nut 302 needs to be manually adjusted. Similarly, a scale line can also be provided on the gantry 6 to detect the position of the second nut 402.

[0032] The above description is merely a preferred embodiment of the present invention and does not limit the implementation and protection scope of the present invention. Those skilled in the art should realize that any equivalent substitutions and obvious changes made based on the description and illustrations of the present invention should be included within the protection scope of the present invention.

Claims

1. A device for acquiring three-dimensional workpiece point clouds, characterized in that, The device includes a base, a first guide rail assembly, a first ball screw pair, a second ball screw pair, a third ball screw pair, a gantry frame, a second guide rail assembly, a connecting plate, a measuring mounting plate, a rotating mechanism, and a point cloud acquisition and measurement component. Two first guide rail assemblies are located at both ends of the base, and the first ball screw pairs are housed within each first guide rail assembly. The gantry frame is located at the upper end of the first guide rail assembly, and two second ball screw pairs are located on the gantry frame. Second guide rail assemblies are mounted on the two second ball screw pairs, and the third ball screw pair is housed within each second guide rail assembly. The connecting plate is located at the lower end of the second guide rail assembly, and the measuring mounting plate is rotatably mounted on the connecting plate. The point cloud acquisition and measurement component is mounted on the measuring mounting plate. The rotating mechanism is located at the upper end of the base and is used to place the workpiece to be measured.

2. The three-dimensional workpiece point cloud acquisition device as described in claim 1, characterized in that, The first guide rail assembly includes a first guide rail and a first slider disposed on the first guide rail, and the gantry frame is connected to the two first sliders; The first ball screw assembly includes a first screw and a first nut disposed on the first screw. The first screw is rotatably disposed within the first guide rail. The first nut is connected to the first slider. The first motor is disposed at one end of the first guide rail and is connected to the first screw.

3. The three-dimensional workpiece point cloud acquisition device as described in claim 1, characterized in that, The second ball screw assembly includes a second screw and a second nut disposed on the second screw. The two ends of the second screw are connected to the gantry frame through screw support seats. The upper end of the gantry frame is provided with a second motor, which is connected to the second screw.

4. The three-dimensional workpiece point cloud acquisition device as described in claim 3, characterized in that, The second guide rail assembly includes a second guide rail and a second slider disposed on the second guide rail. Both ends of the second guide rail are connected to two second nuts, and the connecting plate is connected to the lower end of the second slider.

5. The three-dimensional workpiece point cloud acquisition device as described in claim 4, characterized in that, The third ball screw assembly includes a third screw and a third nut disposed on the third screw. The third screw is disposed inside the second guide rail. The third nut is connected to the second slider. A third motor is disposed at one end of the second guide rail and is connected to the third screw.

6. The three-dimensional workpiece point cloud acquisition device as described in claim 1, characterized in that, The point cloud acquisition and measurement component includes a lidar and a structured light camera. The lidar is mounted on the measurement mounting plate, and two structured light cameras are distributed on both sides of the lidar. A fourth motor is provided on one side of the connecting plate, and the output end of the fourth motor is connected to the measurement mounting plate.

7. The three-dimensional workpiece point cloud acquisition device as described in claim 6, characterized in that, The angle between the axis of the structured light camera and the axis of the lidar is 15°.

8. The three-dimensional workpiece point cloud acquisition device as described in claim 1, characterized in that, The rotating mechanism includes a rotating disk, a support disk, a support rod, and a fifth motor. The fifth motor is installed inside the base, and the rotating disk is installed at the upper end of the base. The output end of the fifth motor is connected to the rotating disk. The support rod is installed at the upper end of the rotating disk, and the support disk is installed at the upper end of the support rod. The upper end of the support disk is used to place the workpiece to be measured.

9. The three-dimensional workpiece point cloud acquisition device as described in claim 8, characterized in that, The support plate is made of transparent silicon carbide.

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