A spherical three-dimensional microtopography measuring instrument and a method of using the same

Abstract

This invention discloses a spherical three-dimensional microscopic topography measuring instrument and its usage method, belonging to the field of precision instrument technology. It includes a fixed base, a first displacement mechanism at the rear end of the top surface of the fixed base, an air-bearing spindle mounted on the first displacement mechanism, a second displacement mechanism mounted on the air-bearing spindle, a workpiece fixture mounted on the second displacement mechanism, a measuring mechanism mounted on the workpiece fixture, a third displacement mechanism at the front end of the top surface of the fixed base, an air-bearing rotary table mounted on the third displacement mechanism, a fourth displacement mechanism mounted on the air-bearing rotary table, and a support base for the workpiece to be measured mounted on the fourth displacement mechanism. This invention, employing the aforementioned spherical three-dimensional microscopic topography measuring instrument and its usage method, utilizes a high-precision industrial camera and a confocal sensor in conjunction to eliminate the large amount of invalid idle time caused by blind exploration and repeated positioning in traditional methods, thus shortening the overall measurement time.

Description

Technical Field

[0001] This invention relates to the field of precision instrument technology, and in particular to a spherical three-dimensional microscopic morphology measuring instrument and its usage method. Background Technology

[0002] In the field of precision instrument technology, accurate measurement of the three-dimensional morphology of spherical or high-curvature microscopic surfaces is of great significance for the quality inspection and performance evaluation of many key components such as precision optical elements, high-end bearings, and biomedical implants. Currently, such measurements mainly rely on high-precision point-scanning sensors (such as white light interferometers and confocal microscopes). Although these sensors have nanometer-level resolution, they are essentially point-by-point scanners with limited measurement fields of view and lack rapid, global perception of the overall morphology of the measured surface. Therefore, before measurement, operators often rely on experience for rough positioning and path planning, resulting in a large number of redundant paths and ineffective movements during the scanning process, leading to low measurement efficiency. Especially for the complete coverage measurement of complex curved surfaces, multiple positioning and sub-region data stitching are often required. However, existing single-modal morphology data lacks high-contrast salient features (such as clear two-dimensional textures) during stitching, causing automated stitching algorithms to face problems such as matching fuzziness, difficulty in iterative convergence, and even failure. This results in a heavy reliance on manual intervention and insufficient automation and intelligence.

[0003] On the other hand, to simultaneously acquire surface geometry and texture information, existing technologies typically employ separate deployments of the topography measurement module and the visual imaging module. This architecture results in the two types of data being acquired at different times, in different spatial coordinate systems, and even on different instrument platforms, requiring subsequent data association and fusion through complex calibration and registration algorithms. This process not only introduces additional alignment errors but also makes it difficult to guarantee strict spatiotemporal consistency between geometric data and texture information. The resulting 3D model is essentially "glued together" rather than a unified fused representation, limiting its application in scenarios requiring rigorous topography-texture correlation analysis (such as comprehensive evaluation of surface defects and functional analysis of micro / nano structures). Summary of the Invention

[0004] The purpose of this invention is to provide a spherical three-dimensional microscopic topography measuring instrument and its usage method. By using a high-precision industrial camera for rapid three-dimensional imaging and intelligent path planning, the confocal sensor is guided to perform measurements with a clear target, eliminating the large amount of invalid idle time caused by blind exploration and repeated positioning in traditional methods, and shortening the overall measurement time.

[0005] To achieve the above objectives, the present invention provides a spherical three-dimensional microscopic morphology measuring instrument, comprising a fixed base, a first displacement mechanism disposed at the rear end of the top surface of the fixed base, an air-bearing spindle disposed on the first displacement mechanism, a second displacement mechanism disposed on the air-bearing spindle, a workpiece fixture disposed on the second displacement mechanism, a measuring mechanism disposed on the workpiece fixture, a third displacement mechanism disposed at the front end of the top surface of the fixed base, an air-bearing rotary table disposed on the third displacement mechanism, a fourth displacement mechanism disposed on the air-bearing rotary table, a workpiece support seat disposed on the fourth displacement mechanism, and a spherical workpiece to be measured disposed on the workpiece support seat.

[0006] Preferably, the measuring mechanism includes a high-precision industrial camera and a confocal sensor. The high-precision industrial camera and the confocal sensor are integrated on the workpiece fixture and located above the spherical workpiece being measured. The high-precision industrial camera is used to acquire macroscopic topographic data including texture features, and the confocal sensor is used to acquire microscopic topographic data.

[0007] Preferably, one end of the workpiece fixture is provided with a rotating shaft for switching the measurement mode of the measuring mechanism, and the rotating shaft is connected to the second displacement mechanism.

[0008] Preferably, the first displacement mechanism includes a first guide rail, which is disposed at the rear end of the top surface of the fixed base. A first slide is disposed on the first guide rail, and the top surface of the first slide is connected to the air-bearing main shaft.

[0009] Preferably, the second displacement mechanism includes a second guide rail, which is disposed at the output end of the air-bearing main shaft. A second slide is disposed on the second guide rail, and the side wall of the second slide is connected to the rotating shaft.

[0010] Preferably, the third displacement mechanism includes a third guide rail, which is disposed at the front end of the top surface of the fixed base, and a third slide is disposed on the third guide rail, the top surface of the third slide being connected to the air-floating rotary table.

[0011] Preferably, the fourth displacement mechanism includes a fourth guide rail, which is disposed at the output end of the air-bearing rotary table. A fourth slide is disposed on the fourth guide rail, and the top surface of the fourth slide is connected to the support base of the workpiece to be tested.

[0012] A method for using a spherical three-dimensional microscopic topography measuring instrument includes the following steps: S1 clamping and fixing: The spherical workpiece to be measured is fixedly installed on the support base of the workpiece to be measured, and the measuring mechanism integrating a high-precision industrial camera and a confocal sensor is fixedly installed on the workpiece fixture; S2 Initial Alignment: The first displacement mechanism moves the air-bearing spindle, the second displacement mechanism, the workpiece fixture, and the measuring mechanism along the first guide rail to adjust the horizontal position of the measuring mechanism. The third displacement mechanism moves the air-bearing rotary table, the fourth displacement mechanism, the workpiece support, and the spherical workpiece to be measured along the third guide rail to adjust the horizontal position of the workpiece, ensuring it is directly below the measuring mechanism. The second displacement mechanism moves the workpiece fixture and the measuring mechanism along the second guide rail to adjust the vertical distance between the measuring mechanism and the workpiece. The fourth displacement mechanism moves the workpiece support and the workpiece to be measured along the fourth guide rail to adjust the radial position of the workpiece, completing the initial alignment and coaxial calibration. S3 Macroscopic Shape Data Acquisition: The air-bearing spindle is started, and the air-bearing spindle drives the second displacement mechanism, workpiece fixture, and measuring mechanism to rotate around the axis of the air-bearing spindle. During the rotation, the high-precision industrial camera continuously acquires macroscopic shape data of the spherical workpiece under test, including texture features. During the acquisition process, the first and second displacement mechanisms adjust the horizontal position and vertical height of the measuring mechanism in real time, and the third and fourth displacement mechanisms adjust the horizontal and radial position of the spherical workpiece under test in real time to ensure that the imaging object distance of the high-precision industrial camera is constant, the acquisition area of ​​the spherical workpiece under test is always at the center of the camera's field of view, and the imaging parameters are within the calibrated effective range. S4: Microscopic morphology data acquisition: Start the rotating shaft, rotate the shaft 180°, switch the measurement mechanism to the confocal sensor, start the air-bearing rotary table, the air-bearing rotary table drives the fourth displacement mechanism, the support base of the workpiece under test and the spherical workpiece under test to rotate around the rotation center of the air-bearing rotary table. During the rotation, the surface of the spherical workpiece under test is scanned point by point by the confocal sensor to obtain the three-dimensional microscopic morphology data of the spherical workpiece under test. During the scanning process, the third and fourth displacement mechanisms adjust the horizontal and radial positions of the spherical workpiece under test in real time, and the first and second displacement mechanisms adjust the horizontal position and vertical height of the confocal sensor in real time to ensure that the measurement spot of the confocal sensor is always perpendicularly incident on the surface of the spherical workpiece under test and within the effective depth of focus. S5 Measurement Output: Outputs the acquired macroscopic topography data and three-dimensional microscopic topography data for subsequent data processing.

[0013] Therefore, the present invention employs the aforementioned spherical three-dimensional microscopic topography measuring instrument and its usage method. Through the high-precision industrial camera's preliminary rapid three-dimensional imaging and intelligent path planning, the confocal sensor is guided to perform measurements with a clear target, eliminating the large amount of invalid idle time caused by blind exploration and repeated positioning in traditional methods, and shortening the overall measurement time.

[0014] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of the spherical three-dimensional microscopic morphology measuring instrument of the present invention.

[0016] Figure Labels 1. Fixed base; 2. Air-bearing spindle; 3. Workpiece fixture; 4. Air-bearing rotary table; 5. Test piece support; 6. Spherical workpiece to be measured; 7. High-precision industrial camera; 8. Confocal sensor; 9. Rotating shaft; 10. First guide rail; 11. First slide; 12. Second guide rail; 13. Second slide; 14. Third guide rail; 15. Third slide; 16. Fourth guide rail; 17. Fourth slide. Detailed Implementation

[0017] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0018] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0019] like Figure 1 As shown, a spherical three-dimensional microscopic morphology measuring instrument includes a fixed base 1. A first displacement mechanism is installed at the rear end of the top surface of the fixed base 1. An air-bearing spindle 2 is installed on the first displacement mechanism. A second displacement mechanism is installed on the air-bearing spindle 2. A workpiece fixture 3 is installed on the second displacement mechanism. A measuring mechanism is integrated on the workpiece fixture 3. A third displacement mechanism is installed at the front end of the top surface of the fixed base 1. An air-bearing rotary table 4 is installed on the third displacement mechanism. A fourth displacement mechanism is installed on the air-bearing rotary table 4. A test piece support 5 is installed on the fourth displacement mechanism. The spherical workpiece 6 to be measured is placed on the test piece support 5. Preferably, the test piece support 5 is a vacuum suction cup. Vacuum suction is activated to fix the spherical workpiece 6 to be measured.

[0020] The measuring mechanism includes a high-precision industrial camera 7 and a confocal sensor 8. Preferably, the workpiece fixture 3 is a double-headed fixture. The high-precision industrial camera 7 is installed on the right side of the workpiece fixture 3, and the confocal sensor 8 is installed on the left side of the workpiece fixture 3. The two are positioned opposite each other and are located directly above the spherical workpiece 6 being measured. In the initial state, the measuring end of the confocal sensor 8 is aligned with the spherical workpiece 6 being measured. The high-precision industrial camera 7 is responsible for quickly acquiring the overall three-dimensional point cloud data and high-contrast two-dimensional texture image of the spherical workpiece 6 being measured before the measurement begins, thereby realizing the global three-dimensional digitization and feature perception of the spherical workpiece 6 being measured. The confocal sensor 8 is responsible for performing detailed micro-morphological measurements of the specific area guided and positioned by the high-precision industrial camera 7 with nanometer-level precision.

[0021] The high-precision industrial camera 7 can adapt to spherical and similar freeform workpieces with diameters from Φ50mm to Φ250mm, and the confocal sensor 8 can achieve a field of view of 1mm×1mm in a single scan, and achieve full surface coverage through splicing.

[0022] The high-precision industrial camera 7 has a positioning accuracy of ±10μm, the confocal sensor 8 has a longitudinal resolution of ≤10nm, a lateral resolution of ≤0.5μm, and a two-dimensional texture resolution of up to 10μm / pixel.

[0023] For typical workpieces, the global 3D scanning and path planning time is less than 30 seconds. For measurement data containing dozens of sub-regions, the fully automatic stitching processing time is less than 2 minutes. Compared with the traditional unguided point-by-point scanning method, the overall measurement efficiency is improved by 50%-80%.

[0024] The first displacement mechanism includes a first guide rail 10, which is fixedly mounted on a protrusion at the rear end of the top surface of the fixed base 1 by a screw. A first slide 11 is sleeved on the first guide rail 10, and the first slide 11 slides along the first guide rail 10. The air-bearing main shaft 2 is fixedly mounted on the top surface of the first slide 11 by a screw.

[0025] The second displacement mechanism includes a second guide rail 12, which is fixedly installed at the output end of the air-bearing spindle 2 by a screw. A second slide 13 is provided on the second guide rail 12, and the second slide 13 slides along the second guide rail 12. The workpiece clamp 3 is fixedly installed on the side wall of the second slide 13 by a screw.

[0026] The third displacement mechanism includes a third guide rail 14, which is fixedly installed on the top front end of the fixed base 1 by a screw. A third slide 15 is provided on the third guide rail 14, and the third slide 15 slides along the third guide rail 14. The air-floating rotary table 4 is fixedly installed on the top surface of the third slide 15 by a screw.

[0027] The fourth displacement mechanism includes a fourth guide rail 16, which is fixedly installed at the output end of the air-float rotary table 4 by a screw. A fourth slide table 17 is provided on the fourth guide rail 16, and the fourth slide table 17 slides along the fourth guide rail 16. The test piece support 5 is fixedly installed on the top surface of the fourth slide table 17 by a screw.

[0028] A method for using a spherical three-dimensional microscopic topography measuring instrument includes the following steps: S1 Clamping and Fixing: Gently place the spherical workpiece 6 to be measured on the workpiece support 5. The workpiece support 5 is opened to activate vacuum adsorption to fix the spherical workpiece 6. The measuring mechanism integrating a high-precision industrial camera 7 and a confocal sensor 8 is fixedly installed on the workpiece fixture 3.

[0029] S2 Initial Alignment: The first displacement mechanism moves the air-bearing spindle 2, the second displacement mechanism, the workpiece fixture 3, and the measuring mechanism along the first guide rail 10 to adjust the horizontal position of the measuring mechanism; the third displacement mechanism moves the air-bearing rotary table 4, the fourth displacement mechanism, the workpiece support 5, and the spherical workpiece 6 to be measured along the third guide rail 14 to adjust the horizontal position of the spherical workpiece 6, so that the spherical workpiece 6 is directly below the measuring mechanism; the second displacement mechanism moves the workpiece fixture 3 and the measuring mechanism along the second guide rail 12 to adjust the vertical distance between the measuring mechanism and the spherical workpiece 6; the fourth displacement mechanism moves the workpiece support 5 and the spherical workpiece 6 along the fourth guide rail 16 to adjust the radial position of the spherical workpiece 6, completing the initial alignment and coaxial calibration.

[0030] S3 Macroscopic Shape Data Acquisition: Start the air-bearing spindle 2. The air-bearing spindle 2 drives the second displacement mechanism, workpiece fixture 3 and measuring mechanism to rotate around the axis of the air-bearing spindle 2. During the rotation, the high-precision industrial camera 7 continuously acquires macroscopic shape data of the spherical workpiece 6 under test, including texture features. During the acquisition process, the first displacement mechanism and the second displacement mechanism adjust the horizontal position and vertical height of the measuring mechanism in real time, and the third displacement mechanism and the fourth displacement mechanism adjust the horizontal position and radial position of the spherical workpiece 6 under test in real time to ensure that the imaging object distance of the high-precision industrial camera 7 is constant, the acquisition area of ​​the spherical workpiece 6 under test is always in the center of the camera's field of view, and the imaging parameters are within the calibrated effective range.

[0031] S4: Microscopic morphology data acquisition: Start the rotating shaft 9, which rotates 180° to switch the measuring mechanism to the confocal sensor 8. Start the air-floating rotary table 4, which drives the fourth displacement mechanism, the workpiece support 5, and the spherical workpiece 6 to rotate around the rotation center of the air-floating rotary table 4. During the rotation, the confocal sensor 8 scans the surface of the spherical workpiece 6 point by point to acquire the three-dimensional microscopic morphology data of the spherical workpiece 6. During the scanning process, the third and fourth displacement mechanisms adjust the horizontal and radial positions of the spherical workpiece 6 in real time, and the first and second displacement mechanisms adjust the horizontal position and vertical height of the confocal sensor 8 in real time to ensure that the measuring spot of the confocal sensor 8 is always perpendicularly incident on the surface of the spherical workpiece 6 and within the effective depth of focus.

[0032] S5 Measurement Output: Outputs the acquired macroscopic topography data and three-dimensional microscopic topography data for subsequent data processing.

[0033] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for using a spherical three-dimensional microscopic topography measuring instrument, comprising the following steps: S1: Clamping and fixing: The spherical workpiece to be measured is fixedly installed on the support base of the workpiece to be measured, and the measuring mechanism integrating a high-precision industrial camera and a confocal sensor is fixedly installed on the workpiece fixture; S2: Initial Alignment: The first displacement mechanism moves the air-bearing spindle, the second displacement mechanism, the workpiece fixture, and the measuring mechanism along the first guide rail to adjust the horizontal position of the measuring mechanism; the third displacement mechanism moves the air-bearing rotary table, the fourth displacement mechanism, the workpiece support, and the spherical workpiece to be measured along the third guide rail to adjust the horizontal position of the workpiece, ensuring it is directly below the measuring mechanism; the second displacement mechanism moves the workpiece fixture and the measuring mechanism along the second guide rail to adjust the vertical distance between the measuring mechanism and the workpiece; the fourth displacement mechanism moves the workpiece support and the workpiece to be measured along the fourth guide rail to adjust the radial position of the workpiece, completing the initial alignment and coaxial calibration. S3: Macroscopic Shape Data Acquisition: The air-bearing spindle is activated, driving the second displacement mechanism, workpiece fixture, and measuring mechanism to rotate around the axis of the air-bearing spindle. During the rotation, a high-precision industrial camera continuously acquires macroscopic shape data of the spherical workpiece, including its texture features. During acquisition, the first and second displacement mechanisms adjust the horizontal and vertical positions of the measuring mechanism in real time, while the third and fourth displacement mechanisms adjust the horizontal and radial positions of the spherical workpiece in real time. This ensures that the imaging object distance of the high-precision industrial camera remains constant, the acquisition area of ​​the spherical workpiece is always at the center of the camera's field of view, and the imaging parameters are within the calibrated effective range. The high-precision industrial camera is responsible for quickly acquiring the overall three-dimensional point cloud data and high-contrast two-dimensional texture image of the spherical workpiece before measurement begins, thereby achieving global three-dimensional digitization and feature perception of the spherical workpiece. S4: Microscopic Topography Data Acquisition: Start the rotating shaft, rotate it 180°, switch the measurement mechanism to the confocal sensor, start the air-bearing rotary table, the air-bearing rotary table drives the fourth displacement mechanism, the workpiece support, and the spherical workpiece to rotate around the rotation center of the air-bearing rotary table. During the rotation, the confocal sensor scans the surface of the spherical workpiece point by point to acquire the three-dimensional microscopic topography data of the spherical workpiece. During the scanning process, the third and fourth displacement mechanisms adjust the horizontal and radial positions of the spherical workpiece in real time, and the first and second displacement mechanisms adjust the horizontal position and vertical height of the confocal sensor in real time to ensure that the measurement spot of the confocal sensor is always perpendicularly incident on the surface of the spherical workpiece and within the effective depth of focus. The confocal sensor is responsible for performing nanometer-level precision microscopic topography measurements on specific areas guided and positioned by the high-precision industrial camera. S5 Measurement Output: Outputs the acquired macroscopic topography data and three-dimensional microscopic topography data for subsequent data processing.

2. A spherical three-dimensional microtopography measuring instrument based on the use method according to claim 1, characterized in that: The device includes a fixed base, a first displacement mechanism at the rear end of the top surface of the fixed base, an air-bearing spindle on the first displacement mechanism, a second displacement mechanism on the air-bearing spindle, a workpiece fixture on the second displacement mechanism, a measuring mechanism on the workpiece fixture, a third displacement mechanism at the front end of the top surface of the fixed base, an air-bearing rotary table on the third displacement mechanism, a fourth displacement mechanism on the air-bearing rotary table, a workpiece support on the fourth displacement mechanism, and a spherical workpiece to be measured on the workpiece support. The measuring mechanism includes a high-precision industrial camera and a confocal sensor. The high-precision industrial camera and the confocal sensor are integrated on the workpiece fixture and located above the spherical workpiece being measured. The high-precision industrial camera is used to acquire macroscopic morphological data including texture features, and the confocal sensor is used to acquire microscopic morphological data.

3. The spherical three-dimensional microscopic morphology measuring instrument according to claim 2, characterized in that: One end of the workpiece fixture is provided with a rotating shaft for switching the measurement mode of the measuring mechanism, and the rotating shaft is connected to the second displacement mechanism.

4. The spherical three-dimensional microscopic morphology measuring instrument according to claim 3, characterized in that: The first displacement mechanism includes a first guide rail, which is disposed at the rear end of the top surface of the fixed base. A first slide is disposed on the first guide rail, and the top surface of the first slide is connected to the air-bearing main shaft.

5. The spherical three-dimensional microscopic morphology measuring instrument according to claim 4, characterized in that: The second displacement mechanism includes a second guide rail, which is disposed at the output end of the air-bearing main shaft. A second slide is disposed on the second guide rail, and the side wall of the second slide is connected to the rotating shaft.

6. The spherical three-dimensional microscopic morphology measuring instrument according to claim 5, characterized in that: The third displacement mechanism includes a third guide rail, which is disposed at the front end of the top surface of the fixed base. A third slide is disposed on the third guide rail, and the top surface of the third slide is connected to the air-float rotary table.

7. The spherical three-dimensional microscopic morphology measuring instrument according to claim 6, characterized in that: The fourth displacement mechanism includes a fourth guide rail, which is disposed at the output end of the air-bearing rotary table. A fourth slide is disposed on the fourth guide rail, and the top surface of the fourth slide is connected to the support base of the test piece.

Images