A positioning method and device for workpiece axis alignment of a machine vision assisted numerical control lathe

Abstract

The application discloses a positioning method and device for workpiece shaft center alignment of a machine vision assisted numerical control lathe, and the positioning method comprises pre-clamping and initial positioning of a part to be processed; point cloud data of a three-dimensional profile of the part to be processed is acquired through a visual scanning assembly; the position of the shaft center line of the part to be processed and the deviation value from the main shaft rotation center line of the numerical control lathe are calculated based on the point cloud data of the three-dimensional profile; the target clamping position of the part to be processed is determined based on the deviation value, so as to realize centering clamping and processing. The application can comprehensively scan shaft parts to acquire three-dimensional profile data of the shaft parts by precisely controlling the motion path of the visual scanning assembly, calculate and determine the shaft center line, and then precisely control the claw, so that the shaft center line of the part coincides with the main shaft center line of the lathe, the centering clamping of the part is completed, and the part is driven to be processed. The application realizes unmanned intelligent clamping alignment, and significantly improves the clamping quality and efficiency of the part.

Description

Technical Field

[0001] The present invention relates to the technical field of mechanical processing equipment, and in particular to a positioning method and device for aligning the axis center of a workpiece of a CNC lathe assisted by machine vision. Background Art

[0002] As a high-precision, high-efficiency, and highly flexible automated machining equipment, CNC lathes are widely used in aerospace, automotive, electronics, and medical equipment. However, when machining shaft parts (shaft blanks or rough-machined parts on CNC lathes), especially those with irregular shaft structures such as eccentric structures, the clamping method has a direct impact on machining accuracy and efficiency. Traditional centering clamping methods include self-centering three-jaw chucks, single-action four-jaw chucks, two-center clamping, and mandrel clamping. However, these solutions have the following limitations:

[0003] First, the clamping force is difficult to control. Too little clamping force may cause parts to slip or fall off, causing vibration and damaging parts and tools. Too much clamping force may cause parts to deform, damage the surface, and accelerate wear of the fixture and machine tools. Second, clamping irregular shaft parts is extremely difficult. For irregular shaft parts such as eccentric structures, the commonly used clamping method cannot ensure that the center of rotation coincides with the spindle axis during processing, thus affecting clamping efficiency and accuracy. Third, the clamping efficiency is very low. The existing clamping method requires manual adjustment, which is difficult to achieve automation and intelligence. Summary of the Invention

[0004] The embodiment of the present invention provides a positioning method and device for machine vision-assisted CNC lathe workpiece axis alignment, so as to solve the technical problems of low clamping efficiency and poor precision in machining irregular shaft parts in the prior art.

[0005] In view of the above technical problems, an embodiment of the present invention provides a positioning method for aligning the axis of a CNC lathe workpiece assisted by machine vision, comprising:

[0006] Pre-clamping and initial positioning of parts to be processed;

[0007] Obtain point cloud data of the three-dimensional contour of the part to be processed by visual scanning components;

[0008] Based on the point cloud data of the 3D contour, calculate the axis centerline position of the part to be processed and the deviation value from the spindle rotation axis centerline of the CNC lathe;

[0009] The target clamping position of the part to be processed is determined based on the deviation value to achieve centering clamping and processing.

[0010] Optionally, the pre-clamping and initial positioning of the workpiece includes:

[0011] The part to be processed is pre-clamped in the servo chuck of the CNC lathe; the jaws on the servo chuck are driven to move linearly, so as to apply a pre-tightening force to the part to be processed; and the rotation of the part to be processed is adjusted.

[0012] Optionally, the step of obtaining point cloud data of a three-dimensional contour of a part to be processed by a visual scanning component includes:

[0013] Drive the visual scanning component to move to one side of the part to be processed, and rotate the optical sensor of the visual scanning component to the direction of the part to be processed;

[0014] Adjust the scanning head of the optical sensor to face the part to be processed;

[0015] The optical sensor is driven to move linearly along the axial direction of the part to be processed to scan the contour of the workpiece and obtain point cloud data of the three-dimensional contour of the part to be processed.

[0016] Optionally, the calculation of the axis centerline position of the part to be processed and the deviation value from the spindle rotation axis centerline of the CNC lathe based on the point cloud data of the three-dimensional contour includes:

[0017] Using the coordinate transformation method, the coordinates of each point are determined by the scanning path of the optical sensor and the vertical distance between the optical sensor and the part to be processed;

[0018] On each circular section, the coordinates of the circle center are calculated by least square fitting;

[0019] Perform least square linear fitting on the center coordinates of each section to calculate the position coordinates of the axis center line of the part to be processed;

[0020] The position coordinates of the axis of the part to be processed are compared with the coordinates of the spindle rotation axis of the CNC lathe to obtain the deviation value.

[0021] Optionally, determining a target clamping position of the part to be processed based on the deviation value to achieve centering clamping and processing includes:

[0022] According to the deviation value, the jaws on the servo chuck are driven to move linearly, thereby adjusting the position of the workpiece to be processed. When the axis of the workpiece to be processed coincides with the axis of rotation of the spindle of the CNC lathe, the target clamping position is set, and the jaws are driven to apply preload force to the workpiece to be processed.

[0023] Adjust the center of the CNC lathe to move to the shaft end of the part to be processed away from the servo chuck to achieve centering clamping of the part to be processed;

[0024] Drive the servo chuck to rotate, control the tool holder of the CNC machine tool to rotate to the preset position of the machining tool, and process the parts to be processed.

[0025] The present invention also provides a positioning device for aligning the axis of a workpiece of a CNC lathe using machine vision assistance, comprising:

[0026] A positioning fixture, which is used to pre-clamp and initially position the parts to be processed;

[0027] A visual scanning component, the visual scanning component is mounted on the tool holder of the CNC lathe and arranged on one side of the part to be processed, the visual scanning component includes an optical sensor, and the optical sensor is used to obtain point cloud data of the three-dimensional contour of the part to be processed;

[0028] A drive assembly, the drive assembly being disposed on a base of the CNC lathe and configured to drive the visual scanning assembly to perform linear motion along the axial direction of the part to be machined;

[0029] A controller, the controller being communicatively connected to the drive assembly, the visual scanning assembly, and the positioning fixture;

[0030] A host computer, wherein a machine executable program is stored in the host computer, and when the controller executes the machine executable program, the positioning method for aligning the axis center of a workpiece of a CNC lathe assisted by machine vision is implemented;

[0031] The top is arranged on the base and is arranged opposite to the positioning fixture. The top is used to clamp the shaft end of the part to be processed away from the positioning fixture.

[0032] Optionally, the positioning fixture includes a servo chuck rotatably mounted on the base and at least two claws slidably mounted on the servo chuck.

[0033] Optionally, the visual scanning assembly includes an optical sensor mounted on the tool holder.

[0034] Optionally, the driving assembly includes a feed base and a driving motor connected to the tool holder, and the driving motor is slidably connected to the feed base.

[0035] The beneficial effects of the present invention are:

[0036] The core of this invention lies in the ingenious integration of machine vision components into the tool holder of a CNC lathe, thereby enabling automated and intelligent pre-machining of parts (particularly shafts, and especially complex parts with eccentric structures) during clamping and alignment. Specifically, this process relies on precisely controlling the motion path of the optical sensor to perform a comprehensive, no-blind-angle scan of the part to be machined, ensuring complete acquisition of its three-dimensional contour data. Subsequently, measurement and computational techniques are used to deeply analyze this three-dimensional data and precisely calculate the part's axis centerline. This process considers both the overall geometry of the part being machined and its subtle local features, ensuring extremely high accuracy in axis centerline positioning. Next, by precisely controlling the clamping action of the servo chuck, the position of the part to be processed is accurately adjusted to ensure that the axis of the part to be processed perfectly coincides with the axis of rotation of the spindle of the CNC lathe. This not only significantly improves the clamping quality and processing accuracy, but also realizes unmanned intelligent operation of the entire clamping process, greatly improving the clamping efficiency and processing quality of the parts to be processed, and providing solid technical support for the CNC lathe to achieve high-precision and high-efficiency processing operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0038] Figure 1 This is a flow chart of a positioning method for aligning the axis of a workpiece of a CNC lathe assisted by machine vision in one embodiment of the present invention;

[0039] Figure 2 This is an overall structural diagram of a positioning device for aligning the axis of a workpiece of a CNC lathe assisted by machine vision in one embodiment of the present invention;

[0040] Figure 3 It is a partial structural diagram of a positioning device for machine vision-assisted axis center alignment of a CNC lathe workpiece in another embodiment of the present invention.

[0041] The reference numerals in the specification are as follows:

[0042] 100-positioning fixture, 110-servo chuck, 120-claw, 200-visual scanning component, 210-optical sensor, 300-drive component, 310-feed base, 320-drive motor, 400-controller, 500-top, 600-parts to be processed, 700-tool holder, 800-base. DETAILED DESCRIPTION

[0043] In order to make the technical problems, technical solutions and beneficial effects solved by the present application clearer, the present application will be further described in detail below in conjunction with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0044] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "radial", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specified.

[0045] In the description of the present application, it should be noted that, unless otherwise specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0046] As shown in Figure 1 An embodiment of the present application provides a positioning method for machine vision assisted workpiece axis alignment of a numerical control lathe, which comprises:

[0047] S10, pre-clamping and initial positioning of the workpiece 600; the step S10 further comprises pre-clamping the workpiece 600 in the servo chuck 110 of the numerical control lathe; driving the jaw 120 on the servo chuck 110 to perform linear motion, driving the jaw 120 to exert a pre-tightening force on the workpiece 600; adjusting the rotation of the workpiece 600.

[0048] Understandably, the pre-clamping and initial positioning of the workpiece 600 is the starting link of the machine vision assisted workpiece axis alignment positioning method of the numerical control lathe, and the core purpose is to preliminarily fix the workpiece 600 on the numerical control lathe, and to provide conditions for subsequent scanning operation through slow rotation. This step ensures that the workpiece 600 can be stably fixed in the servo chuck 110 in the preliminary clamping state through the jaw 120, while avoiding damage to the workpiece due to excessive clamping force.

[0049] S20. Obtain point cloud data of the three-dimensional contour of the part to be processed 600 through the visual scanning component 200. It can be understood that the visual scanning component 200 is used to perform a comprehensive scan on the part to be processed 600 pre-clamped on the CNC lathe to obtain point cloud data of its three-dimensional contour, and the point cloud data is the basis for the subsequent calculation of the axis centerline position.

[0050] In one embodiment, step S20 further includes the following sub-steps:

[0051] S201: Drive the visual scanning assembly 200 to one side of the part 600 to be processed, and rotate the optical sensor 210 of the visual scanning assembly 200 to the direction of the part 600 to be processed. This step ensures that the scanning head of the optical sensor 210 is aligned with the part 600 to be processed. This step ensures that the optical sensor 210 can be aligned with the part 600 to be processed.

[0052] S202. Adjust the scanning head of the optical sensor 210 to face the part to be processed 600. This step ensures that the scanning head of the optical sensor 210 is aligned with the part to be processed 600, ensures that the optical sensor 210 is in the optimal scanning position, and can fully scan the part to be processed 600 in the axial direction to avoid inaccurate scanning data due to position deviation.

[0053] S203: Drive the optical sensor 210 to perform linear motion along the axial direction of the workpiece 600 to scan the contour of the workpiece and obtain point cloud data of the three-dimensional contour of the workpiece 600. This step uses the linear motion of the optical sensor 210 to scan the entire axial contour of the workpiece 600 to obtain accurate point cloud data of its three-dimensional contour. The integrity and accuracy of the point cloud data directly affect the final clamping precision and machining quality.

[0054] It is understandable that the above steps can quickly and accurately obtain the surface topography data of the part 600 to be processed, providing key technical support for realizing automated and intelligent clamping and alignment.

[0055] S30 , calculating the axis centerline position of the to-be-processed part 600 and the deviation value from the main spindle rotation axis centerline of the CNC lathe based on the point cloud data of the three-dimensional contour.

[0056] In one embodiment, step S30 further includes the following sub-steps:

[0057] S301. Using the coordinate conversion method, the coordinates of each point are determined through the scanning path of the optical sensor 210 and the vertical distance between the optical sensor 210 and the part to be processed 600. It is understandable that since the optical sensor 210 moves along a specific path during the scanning process and its relative position with the part to be processed 600 is constantly changing, it is necessary to convert the scanned point cloud data into a unified coordinate system through the coordinate conversion method for subsequent analysis and processing. By considering the scanning path of the optical sensor 210 and the vertical distance between it and the part, the three-dimensional coordinates of each point in the point cloud data are accurately calculated, providing a data basis for the calculation of the axis centerline.

[0058] S302. Calculate the center coordinates of each circular section by fitting using the least squares method. It is understandable that fitting these points using the least squares method can calculate the center coordinates of each circular section, which helps eliminate the influence of measurement errors and noise and improve the calculation accuracy of the center coordinates.

[0059] S303. Perform least squares straight line fitting on the center coordinates of each cross section to calculate the position coordinates of the axis of the part 600 to be processed. It can be understood that this step takes into account the center coordinates of all cross sections, and thus can more comprehensively reflect the actual axis position of the part 600 to be processed.

[0060] S304: Compare the coordinates of the axis of the part 600 to be machined with the coordinates of the spindle axis of the CNC lathe to determine a deviation. By calculating the deviation between these two coordinates, the accuracy of the current clamping position of the part 600 to be machined can be quantitatively assessed, providing a clear basis and direction for subsequent adjustments to the clamping position.

[0061] S40, based on the deviation value, determining the target clamping position of the part to be processed 600 to achieve centering clamping and processing. The step S40 also includes the following sub-steps:

[0062] In one embodiment, S401, based on the deviation value, the jaws 120 on the servo chuck 110 are driven to perform linear motion, thereby adjusting the position of the part 600 to be processed. When the axis of the part 600 to be processed coincides with the axis of rotation of the CNC lathe's spindle, the target clamping position is achieved, and the jaws 120 are driven to apply a preload force to the part 600 to be processed. It can be understood that by controlling the linear motion of the jaws 120 on the servo chuck 110, the position of the part 600 to be processed is precisely adjusted; by continuously adjusting the position of the jaws 120, the axis of the part 600 to be processed coincides with the axis of rotation of the CNC lathe's spindle, thereby ensuring improved processing accuracy; after reaching the target clamping position, the jaws 120 are driven to apply an appropriate preload force to the part 600 to ensure that the part 600 to be processed does not move due to vibration or external forces.

[0063] S402: Adjust the centering point 500 of the CNC lathe to move to the end of the axis of the workpiece 600 away from the servo chuck 110 to achieve centered clamping of the workpiece 600. It can be understood that the centering clamping of the workpiece 600 achieved through the combined action of the centering point 500 and the jaws 120 on the servo chuck 110 can minimize vibration and deviation during the machining process and improve clamping accuracy.

[0064] S403: Drive the servo chuck 110 to rotate, control the tool post 700 of the CNC machine tool to rotate to the preset position of the machining tool, and process the part 600 to be processed. It can be understood that after the part 600 to be processed is accurately centered and clamped and the tool is positioned, the CNC machine tool processing program is started to process the part 600 to be processed.

[0065] In the above-described embodiment of the present invention, a machine vision component is cleverly integrated into the tool holder 700 of a CNC lathe, thereby enabling an automated, intelligent clamping and alignment process for the part 600 to be machined (particularly shaft-type parts, particularly complex parts with eccentric structures) prior to machining. Specifically, this process first relies on precisely controlling the motion path of the optical sensor 210 to perform a comprehensive, no-blind-angle scan of the part, ensuring complete acquisition of its three-dimensional contour data. Subsequently, measurement and computational techniques are used to deeply analyze this three-dimensional data and accurately calculate the part's axis centerline position. This process considers both the overall geometry of the part 600 to be machined and its subtle local features, thereby ensuring extremely high accuracy in the axis centerline position. Next, by precisely controlling the clamping action of the servo chuck 110, the position of the part is accurately adjusted to ensure that the axis of the part perfectly coincides with the axis of rotation of the spindle of the CNC lathe. This not only significantly improves the clamping quality and processing accuracy, but also realizes unmanned intelligent operation of the entire clamping process, greatly improving the clamping efficiency and processing quality of the part 600 to be processed, and providing solid technical support for the CNC lathe to achieve high-precision and high-efficiency processing operations.

[0066] In one embodiment, if Figures 2 to 3 As shown, the present invention also provides a positioning device for aligning the axis of a CNC lathe workpiece with the aid of machine vision, comprising:

[0067] A positioning fixture 100, which is used for pre-clamping and initial positioning of the workpiece 600;

[0068] A visual scanning assembly 200, mounted on the tool post 700 of the CNC lathe and arranged on one side of the part to be processed 600, comprising an optical sensor 210, for acquiring point cloud data of a three-dimensional contour of the part to be processed 600;

[0069] A driving assembly 300, which is disposed on a base 800 of a CNC lathe and is used to drive the visual scanning assembly 200 to perform linear motion along the axial direction of the part to be processed 600;

[0070] A controller 400 , wherein the controller 400 is communicatively connected to the driving assembly 300 , the visual scanning assembly 200 , and the positioning fixture 100 ;

[0071] A host computer (not shown), wherein a machine executable program is stored in the host computer, and when the controller 400 executes the machine executable program, the positioning method for aligning the axis center of a workpiece of a CNC lathe using machine vision assistance is implemented;

[0072] The tip 500 is provided on the base 800 and arranged opposite to the positioning fixture 100 . The tip 500 is used to clamp the workpiece 600 to be processed away from the axial end of the positioning fixture 100 .

[0073] The optical sensor 210 is used to obtain the point cloud data of the three-dimensional contour of the part to be processed 600. The optical sensor 210 is communicated with the host computer, and the host computer sends the point cloud data of the three-dimensional contour to the controller 400. The controller 400 performs centering, clamping and processing on the part to be processed 600 according to the positioning method.

[0074] In one embodiment, if Figures 2 to 3 As shown, the positioning fixture 100 includes a servo chuck 110 rotatably mounted on the base 800 and at least two claws 120 slidably mounted on the servo chuck 110. It is understandable that the number of claws 120 can be four, and the four claws 120 are evenly spaced and arranged on the servo chuck 110, which can flexibly adapt to shaft parts of different shapes and sizes. The servo chuck 110 is connected to the turntable motor, which is mounted on the main shaft of the servo chuck 110 to drive the servo chuck 110 to rotate. It is used for the rotational movement of the part to be processed 600 during the processing of the shaft part, and can achieve precise rotational movement of the part during the processing process to meet the requirements of multi-angle processing. In addition, the servo chuck 110 can also have a built-in servo system, which includes a servo controller 400 and four torque-controlled servo motors. The servo controller 400 and the four torque-controlled servo motors work together to accurately control the four claws 120 on the servo chuck 110 to perform linear motion. This not only allows the clamping movement accuracy to reach an extremely high level, ensuring the precise positioning of the part 600 to be processed, but also allows the clamping force to be precisely controlled to avoid deformation or damage to the part 600 to be processed due to improper clamping force, effectively ensuring the part processing quality and clamping stability.

[0075] In one embodiment, if Figures 2 to 3 As shown, the drive assembly 300 includes a feed base 310 and a drive motor 320 connected to the tool holder 700, and the drive motor 320 is slidably connected to the feed base 310. It can be understood that the feed base 310 is fixedly mounted on the base 800, and a plurality of slide rails are provided on the feed base 310. The drive motor 320 is connected to the slide rails via sliders, and the drive motor 320 can slide on the feed base 310, thereby driving the optical sensor 210 on the visual scanning assembly 200 to run smoothly along a predetermined trajectory, realizing flexible displacement control of the optical sensor 210 in three-dimensional space, ensuring that the scanning trajectory is accurately controllable, and thus realizing complete and detailed collection of three-dimensional contour data of different positions of the part, thereby improving the comprehensiveness and accuracy of data collection.

[0076] In an embodiment, as shown in Figures 2 to 3 Understandably, the tool holder 700 is mounted on the base 800 and can rotate under the driving of the driving motor 320, thereby flexibly adjusting the position of the optical sensor 210 to achieve scanning of the workpiece 600 from different angles and in all directions.

[0077] The working process of the device in the above embodiment of the application is as follows:

[0078] First, the workpiece 600 is preliminarily clamped and pre-tightened. An operator preliminarily clamps the workpiece to be machined in the servo chuck 110 by visual inspection, adjusts the servo chuck 110 to an appropriate angle, and drives the claws 120 to move linearly under the servo motor, so that the four claws 120 simultaneously apply a certain pre-tightening force to the workpiece 600. Then, the rotary table motor is started to drive the servo chuck 110 to rotate, so that the workpiece 600 rotates slowly, preparing for subsequent scanning.

[0079] Secondly, the three-dimensional profile scanning of the workpiece 600 is performed. The optical sensor 210 is started, the feeding base 310 is moved to make the tool holder 700 move to one side of the workpiece 600, the driving motor 320 is started to make the optical sensor 210 rotate to the workpiece direction, so that the scanning head of the optical sensor 210 faces the workpiece 600, so that the complete profile of the workpiece 600 can be scanned. An operator operates the numerical control panel provided on the base 800 to control the optical sensor 210 to move linearly along the axial direction of the workpiece 600 and scan the profile of the workpiece 600. The optical sensor 210 displays the obtained three-dimensional profile data of the workpiece on the numerical control panel. After scanning is completed, the feeding base 310 is adjusted to move, so that the optical sensor 210 retreats to a safe area to avoid affecting the subsequent machining process.

[0080] Then, the calculation of the position of the axis line and the deviation analysis are performed. Based on the three-dimensional profile point cloud data of the workpiece measured by the optical sensor 210, the coordinates of each point are determined by the scanning path of the optical sensor 210 and the vertical distance between the optical sensor 210 and the workpiece by using the coordinate conversion method. On each circumferential section, the center coordinates of the circle are fitted by the least square method. Then, the center coordinates of each section are least square straightly fitted to calculate the position coordinates of the axis line. The coordinates are compared with the coordinates of the spindle rotation axis line of the numerical control lathe to obtain the deviation value of the two.

[0081] Finally, the workpiece is precisely centered, clamped, and processed based on the calculated deviation. Based on the previously calculated coordinate deviation between the axis of the part 600 to be processed and the CNC lathe spindle, the servo motor drives the clamping jaws 120 to perform linear motion again, causing each of the four clamping jaws 120 to move to a position where the axis of the part 600 to be processed coincides with the axis of rotation of the CNC lathe spindle. The centering center 500 is then adjusted to the end of the axis of the part 600 to be processed, completing the centering and clamping. Next, the turntable motor drives the servo chuck 110 to rotate at high speed, controlling the drive motor 320 to rotate the tool holder 700 to the desired position for the processing tool. The part is then processed according to the desired processing technique.

[0082] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention, and should all be included in the scope of protection of the present invention.

Claims

1. A machine vision-assisted CNC lathe workpiece axis alignment positioning method, characterized in that: include: S10, pre-clamping and initial positioning of the part to be processed (600); S20, obtaining point cloud data of the three-dimensional contour of the part to be processed (600) through the visual scanning component (200); S201, driving the visual scanning component (200) to move to one side of the part to be processed (600), and rotating the optical sensor (210) of the visual scanning component (200) to the direction of the part to be processed (600); S202, adjusting the scanning head of the optical sensor (210) to face the direction of the part to be processed (600); S203, driving the optical sensor (210) to perform linear motion along the axial direction of the part to be processed (600) to scan the contour of the workpiece and obtain point cloud data of the three-dimensional contour of the part to be processed (600); S30, calculating the axis centerline position of the part to be processed (600) and the deviation value from the main axis rotation axis of the CNC lathe based on the point cloud data of the three-dimensional contour; S301, using a coordinate conversion method, determining the coordinates of each point through the scanning path of the optical sensor (210) and the vertical distance between the optical sensor (210) and the part to be processed (600); S302, calculating the coordinates of the circle center on each circular cross section by least square fitting; S303, performing least square linear fitting on the center coordinates of each cross section to calculate the position coordinates of the axis of the part to be processed (600); S304, comparing the position coordinates of the axis centerline of the part to be processed (600) with the coordinates of the main spindle rotation axis centerline of the CNC lathe to obtain a deviation value; S40, determining a target clamping position of the part to be processed (600) based on the deviation value to achieve centering clamping and processing; S401, driving the claw (120) on the servo chuck (110) to perform linear motion according to the deviation value, thereby adjusting the position of the part to be processed (600), so that when the axis of the part to be processed (600) coincides with the axis of rotation of the spindle of the CNC lathe as the target clamping position, the claw (120) is driven to apply a pre-tightening force to the part to be processed (600); S402, adjusting the center (500) of the CNC lathe to move to the shaft end of the part to be processed (600) away from the servo chuck (110), so as to achieve centering clamping of the part to be processed (600); S403, driving the servo chuck (110) to perform rotational motion, controlling the tool holder (700) of the CNC machine tool to rotate to a preset position of the machining tool, and machining the part to be machined (600).

2. The machine vision-assisted CNC lathe workpiece axis alignment positioning method according to claim 1 is characterized in that: The step S10 includes: S101, pre-clamping the part to be processed (600) in the servo chuck (110) of the CNC lathe; driving the claw (120) on the servo chuck (110) to perform linear motion, driving the claw (120) to apply a pre-tightening force to the part to be processed (600); and adjusting the rotation of the part to be processed (600).

3. A positioning device for machine vision-assisted CNC lathe workpiece axis alignment, implemented by the machine vision-assisted CNC lathe workpiece axis alignment positioning method according to any one of claims 1-2, characterized in that: include: A positioning fixture (100), the positioning fixture (100) is used to pre-clamp and initially position the part to be processed (600); a visual scanning component (200), the visual scanning component (200) being mounted on a tool holder (700) of the CNC lathe and arranged on one side of the part to be processed (600), the visual scanning component (200) comprising an optical sensor (210), the optical sensor (210) being used to acquire point cloud data of a three-dimensional profile of the part to be processed (600); A drive assembly (300), the drive assembly (300) being arranged on a base (800) of a numerically controlled lathe, the drive assembly (300) being used to drive the visual scanning assembly (200) to perform linear motion along the axial direction of the part to be processed (600); a controller (400), the controller (400) being communicatively connected to the driving component (300), the visual scanning component (200), and the positioning fixture (100); A host computer, wherein a machine executable program is stored in the host computer, and when the controller (400) executes the machine executable program, the positioning method for aligning the axis center of a workpiece of a CNC lathe using machine vision assistance is implemented; A top (500) is provided on the base (800) and arranged opposite to the positioning fixture (100), and the top (500) is used to clamp the part to be processed (600) away from the axial end of the positioning fixture (100).

4. The machine vision-assisted positioning device for aligning the axis of a CNC lathe workpiece according to claim 3 is characterized in that: The positioning fixture (100) comprises a servo chuck (110) rotatably mounted on the base (800) and at least two claws (120) slidably mounted on the servo chuck (110).

5. The machine vision-assisted positioning device for aligning the axis of a CNC lathe workpiece according to claim 3 is characterized in that: The visual scanning assembly (200) includes an optical sensor (210) mounted on the tool holder (700).

6. The machine vision-assisted positioning device for aligning the axis of a CNC lathe workpiece according to claim 5, characterized in that: The driving assembly (300) comprises a feeding base (310) and a driving motor (320) connected to the tool holder (700), wherein the driving motor (320) is slidably connected to the feeding base (310).

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