Water-guided laser machining method, water-guided laser machining device

Abstract

The application discloses a water guide laser processing method and a water guide laser processing device, and the method comprises the following steps: calibrating the XY position conversion relationship of a water guide laser processing head-camera and a camera-probe, and indirectly obtaining the third XY position conversion relationship between the water guide laser processing head center and the probe center; calibrating the Z position conversion relationship between the probe center and the water guide laser processing head center; calculating the XYZ offset between the probe center and the water guide laser processing head center; based on the design drawing of the workpiece, the spatial coordinates of the workpiece are measured by the probe, and the relative position between the water guide laser processing head center and the workpiece is obtained by combining the XYZ offset; and based on the relative position, the water guide laser processing head is used to process the workpiece. Through the correction of the three-dimensional deviation between the probe and the water guide laser processing head, the actual position of the water guide laser processing head relative to the workpiece is determined, the positioning accuracy of the water guide laser focal point in space is improved, and the workpiece processing precision is improved.

Description

Technical Field

[0001] This invention relates to the field of water-guided laser processing technology, and in particular to a water-guided laser processing method and a water-guided laser processing device. Background Technology

[0002] Water-guided laser processing machines equipped with touch probes or capacitive sensors rely on probes to detect the workpiece contour and reference coordinates, and then link the water-guided laser processing head to complete the positioning and processing. The theoretical relative positional relationship between the probe and the water-guided laser head is preset during the equipment design stage. However, in actual use, it has been found that due to limitations such as mechanical assembly tolerances, component deformation, and overall machine assembly processes, unavoidable installation deviations inevitably occur between the probe and the water-guided laser optical axis during the actual assembly process, and the theoretical positional parameters cannot match the actual operating conditions of the equipment.

[0003] Existing technologies rely on preset theoretical parameters to match the probe and the water-guided laser processing head position, without detecting the actual offset of the water-guided laser optical axis relative to the probe, thus ignoring the actual installation errors introduced by assembly. During processing, the workpiece coordinates and dimensions collected by the probe always carry unknown installation deviations. The control system calculates the processing trajectory based on distorted detection data, which directly causes defects such as misalignment and dimensional deviations in water-guided laser processing, significantly reducing the processing accuracy of water-guided laser cutting, welding, and precision drilling. Summary of the Invention

[0004] The technical problem this invention aims to solve is how to improve the accuracy of workpiece position detection in water-guided laser processing to achieve high-precision water-guided laser processing. This invention provides a water-guided laser processing method and equipment. By calculating the actual offset between the water-guided laser processing head and the probe, this offset is used to compensate for the workpiece position measured by the probe, accurately obtaining the relative positional relationship between the workpiece and the water-guided laser processing head, thereby achieving high-precision water-guided laser processing.

[0005] The technical solution adopted by this invention to solve its technical problem is: Firstly, a water-guided laser processing method is provided, comprising: S1. Determine the first XY-axis positional transformation relationship between the center of the water-guided laser processing head and the camera center; S2. Calibrate the second XY-axis position transformation relationship between the camera center and the probe center; S3. Based on the first XY position transformation relationship and the second XY position transformation relationship, obtain the third XY position transformation relationship between the center of the water-guided laser processing head and the center of the probe; S4. Lower the probe and the water-guided laser processing head respectively and bring them into contact with the tool setting device to calibrate the Z-axis position conversion relationship between the center of the probe and the center of the water-guided laser processing head. S5. Calculate the XYZ offset between the probe center and the center of the water-guided laser processing head; S6. Based on the design drawings of the workpiece, and using the probe to measure at least three Mark points of the workpiece to obtain the spatial coordinates of the workpiece, and combining the XYZ offset to calculate the relative position between the center of the water-guided laser processing head and the workpiece; based on the relative position, use the water-guided laser processing head to perform water-guided laser processing on the workpiece.

[0006] Furthermore, step S1 specifically includes: The water-guided laser processing head is moved above the calibration block to perform geometric cutting on the calibration block; the equipment control system records the first mechanical coordinates of the center of the geometric shape. ; The camera captures an image of the geometric shape, the camera center is aligned with the center of the geometric shape, and the equipment control system records the second mechanical coordinates of the camera center. ; According to the first machine coordinates With the second machine coordinate offset between Obtain the first XY position transformation relationship.

[0007] Furthermore, step S2 specifically includes: The probe is used to detect two sides of the calibration block that intersect, and the equipment control system calculates the third mechanical coordinate of the intersection point A of the two sides. ; The camera captures an image of the intersection point A of the calibration blocks, and the equipment control system records the fourth mechanical coordinate of the camera center. ; According to the third mechanical coordinate of the intersection point A With the fourth machine coordinate offset between Obtain the second XY position transformation relationship.

[0008] Furthermore, the process of obtaining intersection point A includes: The probe is placed close to one side of the calibration block and moved along that side, and the first set of position coordinates of the probe when it moves along that side is recorded; Next, place the probe against the other side of the calibration block and move it along that side, recording the second set of position coordinates of the probe as it moves along that side; By performing line fitting on the coordinate points within the first set of position coordinates, the equation of the first line is obtained; By performing line fitting on the coordinate points within the second set of position coordinates, the equation of the second line is obtained; Obtain the third machine coordinates of the intersection point A of the first and second line equations. .

[0009] Furthermore, step S3 specifically includes: The first XY position transformation relationship is as follows: , ; The second XY position transformation relationship is as follows: , ; The second mechanical coordinate of the camera center With the fourth machine coordinate Theoretically the same, therefore the third XY position transformation relationship is as follows: , .

[0010] Furthermore, step S4 specifically includes: The probe is lowered along the Z-axis and touches the tool setting device to obtain the height value of the probe's center. ; The height of the center of the water-guided laser processing head is obtained by lowering the water-guided laser processing head along the Z-axis and bringing it into contact with the tool setting device. ; Calculate the height difference between the probe center and the center of the water-guided laser processing head. ; The Z-axis position transformation relationship is as follows: .

[0011] Furthermore, the first set of position coordinates includes at least three coordinate points at different locations on one edge of the calibration block; The second set of position coordinates includes at least three coordinate points at different locations on the other side of the calibration block.

[0012] Furthermore, the calibration block is shaped to have at least two intersecting straight edges.

[0013] Furthermore, the geometric shape is cross-shaped, circular, or square.

[0014] Secondly, a water-guided laser processing device is provided, comprising: The machine tool is equipped with a worktable, a tool setter, a calibration block, and a three-axis motion component; the worktable is used to place the workpiece. A water-guided laser processing head is mounted on the Z-axis of the three-axis motion component via a mounting plate, and is used to perform water-guided laser processing on the workpiece / calibration block; A probe, mounted on the mounting plate via a first Z-axis moving component, is used to measure the spatial coordinates of the workpiece / calibration block. A camera, mounted on the mounting plate via a second Z-axis moving component, is used to capture images of the workpiece / calibration block. The control system is connected to the water-guided laser processing head, probe, and camera signal, and is used to execute the water-guided laser processing method.

[0015] The beneficial effects of this invention are: This invention indirectly derives the in-plane transformation relationship between the center of the water-guided laser processing head and the probe by calibrating the XY-axis position transformation relationship between the water-guided laser processing head and the camera, and between the camera and the probe. Camera calibration reduces the difficulty of direct alignment calibration. Then, a tool setter is used to contact-calibrate the Z-axis position transformation relationship between the water-guided laser processing head and the probe, and combined with the planar transformation relationship, the three-dimensional offset is obtained, refining the deviation data in the XYZ directions. After acquiring the workpiece's spatial coordinates using the probe, coordinate conversion is performed using the XYZ offsets to correct the three-dimensional deviation between the probe and the water-guided laser processing head caused by assembly. This accurately determines the actual position of the water-guided laser processing head relative to the workpiece, improving the spatial positioning accuracy of the water-guided laser focus, increasing workpiece processing precision, and ensuring the stability of batch processing. Attached Figure Description

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0017] Figure 1 This is a flowchart of the water-guided laser processing method of the present invention.

[0018] Figure 2 This is a schematic diagram of the calibration block of the present invention.

[0019] Figure 3 This is a perspective view of the water-guided laser processing equipment of the present invention.

[0020] Figure 4 This is a top view of the worktable, tool setter, and calibration block of the present invention.

[0021] In the diagram: 1. Machine base; 2. Worktable; 3. Tool setter; 4. Calibration block; 5. Water-guided laser processing head; 6. Probe; 7. Camera; 101. X-axis motion module; 102. Y-axis motion module; 103. Z-axis motion module; 104. Mounting plate; 105. First Z-axis moving component; 106. Second Z-axis moving component. Detailed Implementation

[0022] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0023] like Figure 1As shown, the water-guided laser processing method of this embodiment includes: S1, calibrating the first XY-axis position transformation relationship between the center of the water-guided laser processing head and the center of the camera; S2, calibrating the second XY-axis position transformation relationship between the center of the camera and the center of the probe; S3, obtaining the third XY-axis position transformation relationship between the center of the water-guided laser processing head and the center of the probe based on the first and second XY-axis position transformation relationships; S4, lowering the probe and the water-guided laser processing head respectively and touching them with the tool setter to calibrate the Z-axis position transformation relationship between the center of the probe and the center of the water-guided laser processing head; S5, calculating the XYZ offset between the center of the probe and the center of the water-guided laser processing head; S6, based on the workpiece design drawing, and using the probe to measure at least three Mark points on the workpiece to obtain the spatial coordinates of the workpiece, and combining the XYZ offset to calculate the relative position between the center of the water-guided laser processing head and the workpiece; based on the relative position, performing water-guided laser processing on the workpiece using the water-guided laser processing head.

[0024] Steps S1-S3 sequentially establish the XY-axis positional transformation relationships between the water-guided laser processing head and the camera, and between the camera and the probe, indirectly deriving the transformation relationship between the center of the water-guided laser processing head and the center plane of the probe. Camera calibration reduces the difficulty of direct alignment calibration. Step S4 then uses a tool setter to contact-calibrate the Z-axis positional transformation relationship between the water-guided laser processing head and the probe, combining this with the XY-axis plane transformation relationship to obtain the three-dimensional offset, thus refining the deviation data in the XY and Z directions. Subsequently, after acquiring the workpiece's spatial coordinates using the probe, coordinate conversion is performed using the three-dimensional offset to correct the XY-axis plane deviation and Z-axis height error caused by assembly between the probe and the water-guided laser processing head. This accurately determines the actual position of the water-guided laser processing head relative to the workpiece, avoiding the center offset problem caused by only correcting the plane offset while ignoring the height deviation. This method overcomes the problems of limited installation space and difficult alignment when calibrating the water-guided laser head and probe separately, and achieves three-dimensional direction error compensation, improving the spatial positioning accuracy of the water-guided laser center, increasing workpiece processing precision, and ensuring the stability of batch processing.

[0025] It should be noted that the workpiece's spatial coordinates are used to determine its "spatial orientation." The workpiece design drawings, which include the workpiece's outline dimensions, reference surfaces, and other shape parameters, are pre-imported into the equipment control system. By probing at least three mark points on the workpiece and combining this information with the pre-known workpiece shape parameters, the workpiece's spatial coordinates can be determined.

[0026] In this embodiment, step S1 specifically includes: moving the water-guided laser processing head above the calibration block and performing geometric cutting on the calibration block; the equipment control system recording the first mechanical coordinates of the geometric center. The camera captures images of the geometric shape, and the camera center is aligned with the center of the geometric shape. The equipment control system records the second mechanical coordinate of the camera center. According to the first machine coordinate With the second machine coordinate offset between Obtain the first XY-axis position transformation relationship. For example, the first XY-axis position transformation relationship is: , .

[0027] It should be noted that the geometric shapes can be cross-shaped, circular, square, or grid-like, etc. Each geometric shape has a clearly identifiable center point. After the water-guided laser processing head cuts the geometric shape on the calibration block, the mechanical coordinates of the center of the geometric shape become the mechanical coordinates of the center of the water-guided laser processing head. Then, an image of the geometric shape is captured by a camera, with the camera center aligned with the center of the geometric shape, and the mechanical coordinates of the camera center at that moment are recorded. From this, the mechanical coordinates of both the center of the water-guided laser processing head and the camera center can be obtained, and their XY-axis positional offsets can be calculated.

[0028] In this embodiment, the calibration block is shaped with at least two intersecting straight edges, such as a triangle, square, or pentagon. Step S2 specifically includes: using a probe to detect the two intersecting edges of the calibration block, and the equipment control system calculating the third mechanical coordinate of the intersection point A of the two edges. The camera captures an image of the intersection point A of the calibration blocks, and the equipment control system records the fourth mechanical coordinate of the camera center. Based on the third machine coordinate of intersection point A With the fourth machine coordinate offset between Obtain the second XY-axis position transformation relationship. For example, the second XY-axis position transformation relationship is: , .

[0029] Specifically, the process of obtaining intersection point A includes: moving the probe along one side of the calibration block while keeping it close to that side, and recording the first set of position coordinates of the probe while moving along that side; moving the probe along the other side of the calibration block while keeping it close to that side, and recording the second set of position coordinates of the probe while moving along that side; performing line fitting on the coordinate points in the first set of position coordinates to obtain the first line equation; performing line fitting on the coordinate points in the second set of position coordinates to obtain the second line equation; and obtaining the third mechanical coordinate of the intersection point A of the first and second line equations. .

[0030] For example Figure 2As shown, taking a square calibration block (with four corner points ABCD) as an example, the probe is first moved along the AB side of the square calibration block, and at least three coordinate points at different positions are collected during the movement to form a first set of position coordinates. The least squares method is used to fit a straight line to multiple coordinate points within the first set of position coordinates to obtain the first straight line equation. Next, the probe is moved along the AC side of the square calibration block, and at least three coordinate points at different positions are collected during the movement to form a second set of position coordinates. The least squares method is used to fit a straight line to multiple coordinate points within the second set of position coordinates to obtain the second straight line equation. Then, the mechanical coordinates of the intersection point A of lines AB and AC can be obtained based on the first and second straight line equations. The mechanical coordinates of intersection point A can be used as the mechanical coordinates of the probe center. Then, an image of intersection point A is captured by a camera. During the capture, the camera center is aligned with intersection point A, and the mechanical coordinates of the camera center at this time are recorded. Thus, the mechanical coordinates of both the probe center and the camera center can be obtained, and their positional offsets can be calculated.

[0031] It should be noted that the second mechanical coordinate of the camera center With the fourth machine coordinate Theoretically, they are the same. Therefore, based on the first and second XY-axis position transformation relationships, the third XY-axis position transformation relationship between the center of the water-guided laser processing head and the probe center can be indirectly obtained: , Therefore, the transformation relationship between the center of the water-guided laser processing head and the center of the probe in the XY plane can be obtained.

[0032] In this embodiment, step S4 specifically includes: lowering the probe along the Z-axis to contact the tool setter to obtain the height value of the probe center. The height of the center of the water-guided laser machining head is obtained by lowering the water-guided laser machining head along the Z-axis until it contacts the tool setter. ; Calculate the height difference between the probe center and the center of the water-guided laser processing head. The Z-axis position transformation relationship is as follows: Therefore, the height transformation relationship between the center of the water-guided laser processing head and the center of the probe along the Z-axis can be obtained.

[0033] Next, the XYZ offset between the probe center and the center of the water-guided laser processing head can be calculated. After the probe acquires the spatial coordinates of the workpiece, this XYZ offset can be used. The relative position coordinates of the workpiece with respect to the water-guided laser processing head are obtained, and then the water-guided laser processing head processes the workpiece according to these relative position coordinates.

[0034] This embodiment uses a single calibration block to acquire both the probe reference position and the water-guided laser machining traces. The probe reference position and the water-guided laser machining traces are formed on the same calibration block, eliminating positioning deviations introduced by changing calibration blocks and multiple clamping operations. The measured offset more closely reflects the actual operating conditions of the equipment. The regular shape of the calibration block facilitates reliable probe contact and point acquisition, allowing for precise determination of the reference coordinates. Simultaneously, the water-guided laser machining traces are formed on the surface of the calibration block, allowing for the calculation of the actual offset value of the water-guided laser machining position relative to the probe. This offset is then used to correct the workpiece coordinates measured by the probe, compensating for positional deviations caused by assembly errors, and accurately obtaining the actual position of the workpiece relative to the water-guided laser machining head, avoiding machining trajectory misalignment. Furthermore, the entire calibration method has a simple structure and convenient operation, eliminating the need for separate calibration of multiple sets of tooling. This reduces debugging workload and improves the accuracy of offset calculation, effectively enhancing the positioning accuracy of water-guided laser machining.

[0035] like Figure 3 and Figure 4 As shown, the water-guided laser processing equipment of the present invention includes: a machine base 1, on which a worktable 2, a tool setter 3, a calibration block 4, and a three-axis motion component are provided; the worktable 2 is used to place the workpiece; a water-guided laser processing head 5 is mounted on the Z-axis of the three-axis motion component via a mounting plate 104, and is used to perform water-guided laser processing on the workpiece / calibration block 4; a probe 6 is mounted on the mounting plate 104 via a first Z-axis moving component 105, and is used to measure the spatial coordinates of the workpiece / calibration block 4; a camera 7 is mounted on the mounting plate 104 via a second Z-axis moving component 106, and is used to capture images of the workpiece / calibration block 4; and a control system is signal-connected to the water-guided laser processing head 5, the probe 6, and the camera 7, and is used to execute the water-guided laser processing method.

[0036] Specifically, the three-axis motion components include an X-axis motion module 101, a Y-axis motion module 102, and a Z-axis motion module 103. The Y-axis motion module 102 is mounted on the machine base 1, the X-axis motion module 101 is mounted on the column of the machine base 1, and the Z-axis motion module 103 is mounted on the X-axis motion module 101. In other embodiments, the three-axis motion components can be arranged in other ways. The worktable 2, the tool setter 3, and the calibration block 4 are all mounted on the Y-axis motion module 102, the Z-axis motion module 103 is mounted on the X-axis motion module 101, and the water-guided laser processing head 5 is mounted on the Z-axis motion module 103 via a mounting plate 104. The probe 6 is mounted on the mounting plate 104 via a first Z-axis moving component 105, and the camera 7 is mounted on the mounting plate 104 via a second Z-axis moving component 106. In other words, the Z-axis motion module 103 can drive the water-guided laser processing head 5, probe 6, and camera 7 to move synchronously along the Z-axis. Furthermore, the probe 6 and camera 7 can be independently adjusted in Z-axis position through independent Z-axis moving parts.

[0037] In summary, the water-guided laser processing method and equipment of this invention indirectly derive the transformation relationship between the center of the water-guided laser processing head and the center plane of the probe by calibrating the XY-axis position transformation relationship between the water-guided laser processing head and the camera, and between the camera and the probe. Camera calibration reduces the operational difficulty of direct alignment calibration. Furthermore, the height transformation relationship between the water-guided laser processing head and the probe is calibrated using a tool setter, and the three-dimensional offset is obtained by combining the planar transformation relationship, thus refining the deviation data in the XYZ directions. After acquiring the workpiece's spatial coordinates using the probe, coordinate conversion is performed using the three-dimensional offset, correcting the three-dimensional deviation between the probe and the water-guided laser processing head caused by assembly. This accurately determines the actual position of the water-guided laser processing head relative to the workpiece, improving the spatial positioning accuracy of the water-guided laser focus, enhancing workpiece processing precision, and ensuring the stability of batch processing.

[0038] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A water-guided laser processing method, characterized in that, The method, applied to a five-axis water-guided laser processing device, includes: S1. Determine the first XY-axis positional transformation relationship between the center of the water-guided laser processing head and the camera center; S2. Calibrate the second XY-axis position transformation relationship between the camera center and the probe center; S3. Based on the first XY position transformation relationship and the second XY position transformation relationship, obtain the third XY position transformation relationship between the center of the water-guided laser processing head and the center of the probe; S4. Lower the probe and the water-guided laser processing head respectively and bring them into contact with the tool setting device to calibrate the Z-axis position conversion relationship between the center of the probe and the center of the water-guided laser processing head. S5. Calculate the XYZ offset between the probe center and the center of the water-guided laser processing head; S6. Based on the design drawings of the workpiece, and using the probe to measure at least three Mark points of the workpiece to obtain the spatial coordinates of the workpiece, and combining the XYZ offset to calculate the relative position between the center of the water-guided laser processing head and the workpiece; based on the relative position, use the water-guided laser processing head to perform water-guided laser processing on the workpiece.

2. The water-guided laser processing method as described in claim 1, characterized in that, Step S1 specifically includes: The water-guided laser processing head is moved above the calibration block, and geometric shapes are cut on the calibration block. The equipment control system records the first mechanical coordinates of the center of the geometric shape. ; The camera captures an image of the geometric shape, and the center of the camera is aligned with the center of the geometric shape. The equipment control system records the second mechanical coordinates of the camera center. ; According to the first machine coordinates With the second machine coordinate offset between Obtain the first XY position transformation relationship.

3. The water-guided laser processing method as described in claim 2, characterized in that, Step S2 specifically includes: The probe is used to detect two sides of the calibration block that intersect, and the equipment control system calculates the third mechanical coordinate of the intersection point A of the two sides. ; The camera captures an image of the intersection point A of the calibration blocks, and the equipment control system records the fourth mechanical coordinate of the camera center. ; According to the third mechanical coordinate of the intersection point A With the fourth machine coordinate offset between Obtain the second XY position transformation relationship.

4. The water-guided laser processing method as described in claim 3, characterized in that, The process of obtaining intersection point A includes: The probe is placed close to one side of the calibration block and moved along that side, and the first set of position coordinates of the probe when it moves along that side is recorded; Next, place the probe against the other side of the calibration block and move it along that side, recording the second set of position coordinates of the probe as it moves along that side; By performing line fitting on the coordinate points within the first set of position coordinates, the equation of the first straight line is obtained; By fitting a straight line to the coordinate points within the second set of position coordinates, the equation of the second straight line is obtained; Obtain the third machine coordinates of the intersection point A of the first and second line equations. .

5. The water-guided laser processing method as described in claim 4, characterized in that, Step S3 specifically includes: The first XY position transformation relationship is as follows: , ; The second XY position transformation relationship is as follows: , ; The second mechanical coordinate of the camera center With the fourth machine coordinate Theoretically the same, therefore the third XY position transformation relationship is as follows: , .

6. The water-guided laser processing method as described in claim 5, characterized in that, Step S4 specifically includes: The probe is lowered along the Z-axis and touches the tool setting device to obtain the height value of the probe's center. ; The height of the center of the water-guided laser processing head is obtained by lowering the water-guided laser processing head along the Z-axis and bringing it into contact with the tool setting device. ; Calculate the height difference between the probe center and the center of the water-guided laser processing head. ; The Z-axis position transformation relationship is as follows: .

7. The water-guided laser processing method as described in claim 4, characterized in that, The first set of position coordinates includes at least three coordinate points at different locations on one edge of the calibration block; The second set of position coordinates includes at least three coordinate points at different locations on the other side of the calibration block.

8. The water-guided laser processing method as described in claim 2, characterized in that, The calibration block is shaped to have at least two intersecting straight edges.

9. The water-guided laser processing method as described in claim 2, characterized in that, The geometric shape is a cross, a circle, or a square.

10. A water-guided laser processing device, characterized in that, include: The machine tool is equipped with a worktable, a tool setter, a calibration block, and a three-axis motion component; the worktable is used to place the workpiece. A water-guided laser processing head is mounted on the Z-axis of the three-axis motion component via a mounting plate, and is used to perform water-guided laser processing on the workpiece / calibration block; A probe, mounted on the mounting plate via a first Z-axis moving component, is used to measure the spatial coordinates of the workpiece / calibration block. A camera, mounted on the mounting plate via a second Z-axis moving component, is used to capture images of the workpiece / calibration block. The control system is connected to the water-guided laser processing head, probe, and camera signal, and is used to execute the water-guided laser processing method as described in any one of claims 1-9.

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