Automatic speckle preparation device and method

Abstract

The invention discloses an automatic speckle preparation device and method, and relates to the technical field of speckle manufacturing, and the device comprises a camera module, a five-degree-of-freedom movement mechanism, an axial feeding mechanism and a system control module. The camera module is used for collecting the appearance of the dispensing pen and original appearance image data of the surface of the test piece; the system control module is used for executing the steps of reconstructing the morphology of the point coating pen and calibrating the posture of the point coating pen and the spatial position of a pen point; reconstructing the morphology of the test piece; obtaining the speckle size and distribution requirements according to the morphology characteristics of the test piece and the loading test parameters; planning a spot coating pen track according to the speckle size and distribution requirements; and controlling the five-degree-of-freedom movement mechanism to drive the point coating pen to move until the axis is vertical to the tangent plane of the target point according to the track of the point coating pen, and then controlling the axial feeding mechanism to drive the point coating pen to feed until the pen point is in contact with the target point at the set pressure. The method has the advantages of high efficiency and high quality.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of speckle preparation, in particular to a speckle automatic preparation device and method. BACKGROUND

[0002] Porous buffer energy absorption grid structure is widely used in automobile crash components, and the deformation behavior monitoring and accurate measurement of deformation are crucial for structure improvement and mechanical property improvement. At present, the mechanical behavior evaluation of the grid structure can be mainly divided into subjective observation and non-contact measurement methods, wherein the non-contact measurement method mainly adopts the digital image correlation (DIC) method. DIC has the following advantages: (1) simple experimental equipment and light path, easy to operate; (2) full-field non-contact measurement; (3) low requirement for light and other environmental factors. However, when DIC is used for deformation measurement, the surface to be measured needs to be attached with sufficient speckle information as a deformation carrier to solve the deformation information by using images.

[0003] The existing speckle preparation methods mainly include pressure spraying, printing, scraping, coating, etching, mixed liquid deposition and focused ion beam methods, but the existing methods are difficult to operate or difficult to adjust and control the speckle parameters. SUMMARY

[0004] The purpose of the present application is to provide a speckle automatic preparation device and method to solve the problems existing in the prior art, which has the advantages of high efficiency and high quality.

[0005] To achieve the above-mentioned purpose, the present application provides the following solutions:

[0006] The present application provides a speckle automatic preparation device, which comprises a camera module, a five-degree-of-freedom motion mechanism, an axial feeding mechanism and a system control module; the camera module is used to collect the appearance of the point pen and the original topographic image data of the specimen surface; the five-degree-of-freedom motion mechanism is used to realize the translation of X, Y and Z axes and the pitching and yawing rotation; the axial feeding mechanism is installed at the end of the five-degree-of-freedom motion mechanism, and the end of the axial feeding mechanism is used to install the point pen, and the feeding direction of the end of the axial feeding mechanism is parallel to the axial direction of the point pen; the system control module is used to perform: point pen appearance reconstruction, calibration of point pen posture and pen tip spatial position; specimen topography reconstruction; obtaining speckle size and distribution requirements according to specimen topographic features and loading test parameters; planning point pen trajectory according to speckle size and distribution requirements; after the point pen is moved to the plane perpendicular to the target point axis by controlling the five-degree-of-freedom motion mechanism according to the point pen trajectory, the point pen is fed by controlling the axial feeding mechanism until the pen tip contacts the target point with the set pressure.

[0007] In some embodiments, a test piece mounting and pose adjusting mechanism is further included for adjusting the pose of the test piece so that any point to be painted surface of the test piece can be located within the painting range of the point painting pen.

[0008] In some embodiments, after the test piece topography reconstruction, the system control module is further used for region segmentation of the test piece surface, and the system control module sequentially completes speckle production of each region according to the region segmentation result.

[0009] In some embodiments, a force sensor is further included for monitoring the axial pressure applied to the point painting pen by the axial feeding mechanism in real time; the system control module pre-stores a speckle size-pressure calibration corresponding relationship curve or model, and dynamically adjusts the feeding amount of the force sensor based on the force sensor feedback.

[0010] In some embodiments, the five-degree-of-freedom motion mechanism includes an XYZ motion mechanism, a yaw mechanism and a pitch mechanism, the XYZ motion mechanism is used to drive the point painting pen to move horizontally along the X, Y and Z axes, the yaw mechanism is used to drive the point painting pen to yaw, and the pitch mechanism is used to drive the point painting pen to pitch.

[0011] In some embodiments, the XYZ motion mechanism includes an X-axis motion mechanism, a Y-axis motion mechanism and a Z-axis motion mechanism, the Z-axis motion mechanism is arranged at the free end of the X-axis motion mechanism, the Y-axis motion mechanism is arranged at the free end of the Z-axis motion mechanism, the X-axis motion mechanism includes an X-axis motion frame and an X-axis guide rail, the X-axis motion frame is a portal frame structure, the X-axis motion frame is slidably arranged on the X-axis guide rail, the Z-axis motion mechanism is arranged on one side of the X-axis motion frame, and a counterweight is arranged on the other side of the X-axis motion frame.

[0012] In some embodiments, a camera module motion mechanism is further included for driving the camera module to move along the horizontal direction towards or away from the test piece.

[0013] The present application further provides a method for automatically producing speckles by using the speckle automatic production device as described above, which comprises the following steps:

[0014] S1: point painting pen topography reconstruction, calibration of the pose of the point painting pen and the spatial position of the pen tip;

[0015] S2: test piece topography reconstruction;

[0016] S3: obtaining speckle size and distribution requirements according to the topography characteristics of the test piece and the loaded test parameters;

[0017] S4: planning a point painting pen trajectory according to the speckle size and distribution requirements;

[0018] S5: According to the point pen track control five degrees of freedom motion mechanism drives the point pen to move to the axis perpendicular to the target point tangent plane, then control the axial feed mechanism drives the point pen to feed until the pen tip contacts the target point with the set pressure;

[0019] S6: Repeat step S5 until all the target point speckle production is completed.

[0020] In some embodiments, the system control module performs the specimen topography reconstruction, and is further used for region segmentation of the specimen surface.

[0021] In some embodiments, it further comprises S7: rotating the specimen and repeating steps S2-S6 until all the speckle production on the specimen is completed.

[0022] It further comprises S8: using the camera module to collect images for speckle quality evaluation, and using the system control module to control the point pen for secondary point coating for the region with poor point coating quality.

[0023] The present application has the following technical effects compared with the prior art:

[0024] The present application uses mechanical motion method to prepare speckles, which reduces the cost of etching process, focused ion beam and other speckle preparation methods, and improves the controllability of speckle size parameters and the flexibility of speckle preparation for different specimens compared with spraying process, scraping, mixed liquid deposition and other methods.

[0025] The present application uses three-dimensional topography data to control the five degrees of freedom motion mechanism and the axial feed mechanism to drive the point pen to move accurately, so that the point pen feeds along the axis perpendicular to the target point tangent plane, which reduces the speckle size deviation caused by the deviation of the point pen axis relative to the normal of the target point, and the force sensor feedback can effectively control the speckle size.

[0026] The present application can prepare speckles on the surface of complex grid structure, and the size of the grid cell wall is narrow, so the boundary gray scale information is very important. The program control can be used for regional speckle preparation, and high-efficiency full-surface speckle preparation can be realized by optimizing the motion path of the point pen.

[0027] In summary, the speckle automatic preparation device and method provided by the present application can prepare speckles on the surface of three-dimensional grid type porous structure, and the preparation can be realized automatically, with high efficiency and good precision, which effectively reduces the workload of artificial speckle preparation when the digital image correlation method is used for detection in the mechanical test verification stage of the grid structure. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to make the technical solutions in the embodiments of the present application or the prior art clearer, the accompanying drawings needed in the embodiments will be briefly introduced. Obviously, the accompanying drawings in the following description only represent some embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative effort based on these drawings.

[0029] Fig. 1 The schematic diagram of the overall structure of the device provided for Embodiment 1.

[0030] Fig. 2 The schematic diagram of the flow of a specific embodiment in the method provided for Embodiment 2.

[0031] Fig. 3 The schematic diagram of the partial structure of the grid structure and the local enlarged view of the grid structure, which shows the area segmentation and the speckle distribution thereon; a, b, c, d and e in the local enlarged view represent five different areas respectively.

[0032] In the figure: 1-system control module; 2-camera module; 3-force sensor; 4-yaw mechanism and pitch mechanism; 5-XYZ motion mechanism; 6-optical vibration isolation table; 7-dot pen; 8-test piece; 9-axial feeding mechanism; 10-mounting and pose adjustment mechanism; 11-camera module motion mechanism; 12-tool and raw material box. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments only represent some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort belong to the scope of protection of the present application.

[0034] The purpose of the present application is to provide a speckle automatic preparation device and method to solve the problems in the prior art, which has the advantages of high efficiency and high quality.

[0035] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] Firstly, some technical terms involved in the embodiments of the present application will be introduced.

[0037] Loading test parameters, i.e. the required speckle size range and distribution (density) range when using DIC for deformation measurement.

[0038] Target point, i.e. the position point to be dot-coated, i.e. the speckle to be formed at the target point.

[0039] The speckle preparation in the prior art generally uses an etching process, which needs to use electron beam lithography technology or ultraviolet lithography technology, and has high requirements for equipment, and needs to constantly adjust etching parameters and deposition parameters for different sizes of speckles, and has high cost; and for a common spraying process used in a common laboratory, it is difficult to control the size parameters of the speckles due to the influence of parameters such as spraying distance, pressure, and nozzle size; for a printing process, common methods include stamp printing, roller printing, and water transfer printing, the first two methods are difficult to be used for curved surface speckle preparation, and the latter method generally needs to be stacked through 6 layers of materials, and the process is relatively complex.

[0040] The embodiments of the present application are described below in combination with Figs. 1 to 3 .

[0041] Embodiment one

[0042] The present application provides a speckle automatic preparation device, comprising a camera module 2, a five-degree-of-freedom motion mechanism, an axial feeding mechanism 9, and a system control module 1; the camera module 2 is used for collecting point pen 7 topography and original topography image data of a test piece 8 surface; the five-degree-of-freedom motion mechanism is used for realizing X, Y, Z axis translation and pitching, yawing rotation; the axial feeding mechanism 9 is installed at the end of the five-degree-of-freedom motion mechanism, and the end of the axial feeding mechanism 9 is used for installing the point pen 7, and the feeding direction of the end of the axial feeding mechanism 9 is parallel to the axial direction of the point pen 7; the system control module 1 is used for performing: point pen 7 topography reconstruction, calibration of the point pen 7 posture and pen tip space position; test piece 8 topography reconstruction; obtaining speckle size and distribution requirements according to test piece 8 topography characteristics and loaded test parameters; planning a point pen 7 trajectory according to the speckle size and distribution requirements; after the five-degree-of-freedom motion mechanism drives the point pen 7 to move to a target point tangent plane with the axial direction perpendicular to the target point tangent plane according to the point pen 7 trajectory, the axial feeding mechanism 9 drives the point pen 7 to feed until the pen tip contacts the target point with a set pressure.

[0043] The present application uses mechanical motion to prepare speckles, which reduces the cost of etching process, focused ion beam, and other speckle preparation methods, and improves the controllability of speckle size parameters and the flexibility of speckle preparation for different test pieces 8 compared with spraying process, scraping, and mixed liquid deposition.

[0044] Most importantly, the application can make the axis of the point coating pen 7 perpendicular to the tangent plane of the target point, which is conducive to controlling the size and shape of the point coating speckle by controlling the feed displacement of the axial feed mechanism 9, thereby improving the point coating quality. On the other hand, if the axis of the point coating pen 7 is not perpendicular to the tangent plane of the target point and the point coating is performed from a single direction, the angle between the axis of the point coating pen 7 and each target point will not be completely the same due to the curved surface of the test piece 8. When the point coating pen 7 is controlled with the same pressure, the shape of the point coating speckle will be irregular and it is difficult to control the size of the speckle, thereby resulting in poor point coating quality. The application moves the point coating pen 7 to make the axis perpendicular to the tangent plane of the target point to overcome the above-mentioned defects.

[0045] In the formula, the positions of the target points are distributed according to the speckle diagram evaluation index after the spatial curved surface is fitted from the point cloud data; the tangent plane of the target point is fitted from the adjacent point cloud data, and the intersection of the feed axis of the point coating pen 7 and the tangent plane is the target point.

[0046] The test piece 8 can be a grid structure, and the surface of the grid structure is a porous structure. By obtaining the surface topography and boundary information, the motion of the point coating pen 7 is controlled by using the five-degree-of-freedom motion mechanism, and high-quality speckles can be prepared on the entire grid structure.

[0047] In some embodiments, the end of the axial feed mechanism 9 is provided with a clamping mechanism, and the point coating pen 7 is clamped and fixed by the clamping mechanism.

[0048] In some embodiments, the embodiment of the application further includes a test piece 8 mounting and pose adjustment mechanism 10, which is used to adjust the pose of the test piece 8 so that any surface to be point coated of the test piece 8 can be located within the point coating range of the point coating pen 7.

[0049] This embodiment facilitates automatic speckle point coating of the test piece 8 in all directions. After adjusting the pose of the test piece 8 each time, the topography of the test piece 8 needs to be obtained again, the speckle size and distribution requirements need to be formulated, and the trajectory of the point coating pen 7 needs to be formulated.

[0050] It can be understood that in some embodiments, the test piece 8 can also be manually changed in pose to perform speckle point coating in all directions.

[0051] In some embodiments, after the system control module 1 performs the test piece 8 topography reconstruction, it is also used for region segmentation of the surface of the test piece 8. The system control module 1 sequentially completes the speckle production of each region according to the region segmentation result.

[0052] For example, the system control module 1 can be a computer, a single-chip computer, a programmable logic controller (PLC), a programmable automation controller (PAC), or the like. Fig. 3As shown, after the sub-regions, the speckle manufacturing mode of each region in turn is beneficial to realize efficient collision-free path planning, and the preferred sub-region logic needs to meet that the segmented region does not contain a hole structure, which can realize that the path is approximately in the shape of a zigzag trajectory when dotting, so that the path is shorter when dotting the target point in any region, and the efficiency is improved. After completing the dotting in a region, the dotting pen 7 can be moved to the next adjacent region for dotting.

[0053] In some embodiments, the embodiment of the application further comprises a force sensor 3 for monitoring the axial pressure applied by the axial feed mechanism 9 to the dotting pen 7 in real time; the system control module 1 pre-stores a speckle size-pressure calibration corresponding relationship curve or model, and dynamically adjusts the feed amount of the force sensor 3 based on the feedback of the force sensor 3.

[0054] This embodiment monitors the force of the axial feed of the dotting pen 7 in real time through the force sensor 3, thereby controlling the speckle size, and the corresponding relationship between the speckle size and the force sensor 3 data is pre-calibrated and fitted. The corresponding relationship can be represented by a corresponding relationship curve, a model or any other form.

[0055] In some embodiments, the five-degree-of-freedom motion mechanism includes an XYZ motion mechanism 5, a yaw mechanism and a pitch mechanism 4, the XYZ motion mechanism 5 is used to drive the dotting pen 7 to move horizontally along the X, Y and Z axes, the yaw mechanism is used to drive the dotting pen 7 to rotate in yaw, and the pitch mechanism is used to drive the dotting pen 7 to rotate in pitch.

[0056] This embodiment provides a specific way to realize five degrees of freedom.

[0057] In some embodiments, the XYZ motion mechanism 5 includes an X-axis motion mechanism, a Y-axis motion mechanism and a Z-axis motion mechanism, the Z-axis motion mechanism is arranged at the free end of the X-axis motion mechanism, the Y-axis motion mechanism is arranged at the free end of the Z-axis motion mechanism, the X-axis motion mechanism includes an X-axis motion frame and an X-axis guide rail, the X-axis motion frame is a portal frame structure, the X-axis motion frame is slidably arranged on the X-axis guide rail, the Z-axis motion mechanism is arranged on one side of the X-axis motion frame, and a counterweight is arranged on the other side of the X-axis motion frame.

[0058] This embodiment realizes the purpose of balancing the front and back sides of the whole structure by the counterweight, avoiding tilting or shaking.

[0059] In some embodiments, the embodiment of the application further comprises a camera module motion mechanism 11 for driving the camera module 2 to move along the horizontal direction towards or away from the test piece 8.

[0060] The embodiment realizes the purpose of automatically moving the camera module 2 to the work station or returning to the zero point away from the work station. The zero point is the initial position of the camera module 2, which is away from the work station to avoid affecting the dot coating process when dot coating.

[0061] Specifically, the camera module 2 and the dot coating pen 7 are calibrated at the work station, and then return to the respective zero points to avoid mutual interference during detection and dot coating; in the mechanism for driving the movement of the camera and the dot coating pen 7, each degree of freedom movement has a position and angle encoder, which can record the current position in real time after calibration; the system control module 1 controls the camera module 2, including position calibration, image processing and point cloud processing, optimizes the movement trajectory of each region dot coating pen 7 according to the topographic data and speckle requirements, and controls each degree of freedom movement of the dot coating pen 7; the dot coating pen 7 makes small displacement movement on the surface of the sample 8, and continuously dots the speckle optimized by the controller on the sample surface.

[0062] In some embodiments, the camera module movement mechanism 11 is arranged on a support rod which can be lifted, so as to facilitate adjusting the height of the camera module 2 to adapt to different samples 8.

[0063] In some embodiments, the camera module 2 is a binocular depth camera.

[0064] In some embodiments, a tool and raw material box 12 is further included.

[0065] In some embodiments, an optical vibration isolation table 6 is further included, which serves as a support structure of other modules to improve the stability of speckle preparation and thus improve the quality of speckle preparation.

[0066] Embodiment two

[0067] The application further provides a speckle automatic preparation method using the speckle automatic preparation device of the embodiment one, comprising:

[0068] S1: topographic reconstruction of the dot coating pen 7, calibration of the posture and spatial position of the pen tip of the dot coating pen 7;

[0069] S2: topographic reconstruction of the sample 8;

[0070] S3: obtaining speckle size and distribution requirements according to the topographic characteristics of the sample 8 and the loaded test parameters;

[0071] S4: planning the trajectory of the dot coating pen 7 according to the speckle size and distribution requirements;

[0072] S5: after the five-degree-of-freedom movement mechanism drives the dot coating pen 7 to move to the axis perpendicular to the target point tangent plane according to the trajectory of the dot coating pen 7, the axial feeding mechanism 9 drives the dot coating pen 7 to feed until the pen tip contacts the target point with the set pressure;

[0073] S6: repeat step S5 until the speckle making at all target points is completed.

[0074] This embodiment has all the advantages of embodiment one, and will not be repeated here.

[0075] In some embodiments, the system control module 1 is further configured to perform region segmentation on the surface of the test piece 8 after the surface reconstruction of the test piece 8, and the system control module 1 sequentially completes speckle making of each region according to the region segmentation result.

[0076] In some embodiments, the method further comprises S7: rotating the test piece 8 and repeating steps S2-S6 until all speckle making on the test piece 8 is completed.

[0077] The method further comprises S8: using the camera module 2 to collect images for speckle quality evaluation, and using the system control module 1 to control the point pen 7 to perform secondary point coating for regions with poor point coating quality.

[0078] In some embodiments, the positions between the speckle spots on the surface of the test piece 8 have a certain randomness, which is optimized by the system control module 1, so that the speckles are not textured but random, as shown in Fig. 3 .

[0079] In some embodiments, when designing the speckles, the focus is on the speckles at the cell wall boundary. For example, the number of speckles at the boundary can be set to be a little more, and the speckles are preferably located inside the boundary to avoid incomplete speckles on the cell wall surface due to the suspended point pen 7 head during point coating. This is because the grid structure cell wall has a small thickness, and sufficient gray scale information needs to be provided at the boundary when performing digital image correlation calculation.

[0080] The present application can change the point pen 7 tip size, speckle raw material concentration, speckle raw material color and other parameters according to the test requirements, prepare speckles with different randomness, coverage, size and color, and prepare speckles with different sizes on the same surface according to different feeding distances of the point pen 7 axis feeding direction, to realize multi-scale speckle preparation.

[0081] The present application can realize pose transformation of test pieces 8 with different shapes by replacing the test piece pose adjustment mechanism.

[0082] When used for the first time, the test piece 8 is installed to an initial position, the camera module 2 and the point pen 7 are respectively moved to above the test piece 8, the point pen 7 is close to the highest position of the test piece 8, the appearance of the point pen 7 is reconstructed, the posture and the pen tip position of the point pen 7 are calibrated, and the point pen 7 returns to a zero position; the camera module 2 is used to shoot the test piece 8 at the current position, the three-dimensional appearance is obtained, and the image processing technology and the point cloud processing technology are used to segment the cell wall of the grid structure, so that the cell wall surface in the same region is more conducive to the trajectory planning of the point pen 7; according to the morphology characteristics of different regions and the test parameters loaded, the speckle size and distribution requirements are obtained, then the system control module 1 is used to control the posture change path, the speckle spot size and distribution of the point pen 7, and the axis of the point pen 7 is perpendicular to the target point tangent plane feeding; after the current surface is painted, the installation and posture adjusting mechanism 10 is used to adjust the position of the test piece 8, and the above steps are performed on the current surface until the speckle point painting on the entire circumferential surface is completed.

[0083] The principles and implementation manners of the present application are described by using specific examples in the present application, and the above examples are only used to help understand the method of the present application and its core idea; meanwhile, for the general technical personnel in the field, the specific implementation manners and application ranges will be changed according to the idea of the present application. In conclusion, the content of the present specification should not be understood as the limitation of the present application.

Claims

1. A speckle auto-preparation device, characterized by: include: The camera module is used to acquire image data of the shape of the dotting pen and the original shape of the specimen surface; A five-degree-of-freedom motion mechanism is used to realize translation along the X, Y, and Z axes, as well as pitch and yaw rotation. An axial feed mechanism is installed at the end of the five-degree-of-freedom motion mechanism. The end of the axial feed mechanism is used to mount a dotting pen, and the feed direction of the end of the axial feed mechanism is parallel to the axis of the dotting pen. The system control module is used to execute: Reconstructing the shape of the dotting pen, and calibrating the pen's posture and the spatial position of its tip; Specimen morphology reconstruction; The required speckle size and distribution are obtained based on the specimen morphology and loading test parameters. Plan the dot painting trajectory based on the required speckle size and distribution; Based on the trajectory of the dotting pen, the five-degree-of-freedom motion mechanism drives the dotting pen to move until its axis is perpendicular to the tangent plane of the target point. Then, the axial feed mechanism is controlled to drive the dotting pen to feed until the pen tip contacts the target point with the set pressure.

2. The speckle auto-preparation apparatus according to claim 1, characterized by: It also includes a specimen installation and posture adjustment mechanism, which is used to adjust the posture of the specimen so that any surface of the specimen to be dotted can be located within the dotting range of the dotting pen.

3. The speckle auto-preparation apparatus according to claim 1, characterized by: After the system control module performs specimen morphology reconstruction, it is also used to segment the specimen surface into regions. The system control module sequentially completes speckle fabrication for each region based on the region segmentation results.

4. The speckle auto-preparation apparatus according to claim 1, characterized by: It also includes a force sensor, which is used to monitor the axial pressure applied to the dotting pen by the axial feed mechanism in real time; the system control module pre-stores the speckle size-pressure calibration curve or model, and dynamically adjusts the feed amount of the force sensor based on the feedback from the force sensor.

5. The speckle auto-preparation apparatus according to claim 1, characterized by: The five-degree-of-freedom motion mechanism includes an XYZ motion mechanism, a yaw mechanism, and a pitch mechanism. The XYZ motion mechanism is used to drive the dotting pen to translate along the X, Y, and Z axes. The yaw mechanism is used to drive the dotting pen to yaw rotation. The pitch mechanism is used to drive the dotting pen to pitch rotation.

6. The speckle auto-preparation apparatus according to claim 5, characterized by: The XYZ motion mechanism includes an X-axis motion mechanism, a Y-axis motion mechanism, and a Z-axis motion mechanism. The Z-axis motion mechanism is located at the free end of the X-axis motion mechanism, and the Y-axis motion mechanism is located at the free end of the Z-axis motion mechanism. The X-axis motion mechanism includes an X-axis motion frame and an X-axis guide rail. The X-axis motion frame is a gantry structure and is slidably mounted on the X-axis guide rail. The Z-axis motion mechanism is located on one side of the X-axis motion frame, and a counterweight is constructed on the other side of the X-axis motion frame.

7. The speckle auto-preparation apparatus according to claim 1, characterized by: It also includes a camera module motion mechanism, which is used to drive the camera module to move horizontally toward or away from the specimen.

8. A method for automatically preparing speckle patterns using the automatic speckle pattern preparation device according to any one of claims 1 to 7, characterized in that: S1: Reconstruction of the shape of the dotting pen, and calibration of the pen posture and the spatial position of the pen tip; S2: Specimen morphology reconstruction; S3: Obtain the speckle size and distribution requirements based on the specimen morphology and loading test parameters; S4: Plan the dot painting trajectory based on the speckle size and distribution requirements; S5: According to the point pen track control five degrees of freedom motion mechanism drives the point pen to move to the axis perpendicular to the target point tangent plane, control the axial feed mechanism drives the point pen to feed until the pen tip and the target point with the set pressure contact; S6: Repeat step S5 until all the target point at the speckle production.

9. The method of claim 8, wherein: The system control module is further used for region segmentation of the test piece surface after performing the test piece topography reconstruction, and the system control module sequentially completes speckle production of each region according to the region segmentation result.

10. The method of claim 9, wherein: Further comprising S7: Rotate the test piece, and repeat steps S2-S6 until all speckle production on the test piece is completed. Further comprising S8: Use the camera module to collect images for speckle quality evaluation, and use the system control module to control the point pen for secondary point coating for the region with poor point coating quality.

Images