Error compensation method for plate size detection

Abstract

The application discloses a kind of error compensation methods of plate size detection, it is related to plate processing technical field.The application includes workpiece plate length detection system, workpiece plate width detection system, workpiece plate thickness detection system, plate length error compensation, suppose plate length is x, hole position x direction coordinate is x1, actual measurement calculation plate width is x2, except the hole position positioned in horizontal direction, other hole positions if exceed half of plate length x / 2, all need to carry out offset compensation in X direction, i.e.suppose plate length is x, hole position x direction coordinate is x1, actual measurement calculation plate width is x2, if x1>x / 2 value, X=x1-(x-x2), X is the value after compensation, plate width error compensation, suppose plate width is y, hole position y direction coordinate is y1, the length, width and thickness of the plate processing are detected and compensated in the application, can improve the machining precision of numerical control drilling center, facilitate subsequent assembly of plate, improve the machining quality of product.

Description

Technical Field

[0001] This invention relates to the field of sheet metal processing technology, specifically to an error compensation method for sheet metal size detection. Background Technology

[0002] In the field of woodworking machinery, processes such as grooving, drilling, and milling of wood boards are frequently involved. CNC drilling centers are automated equipment primarily used for drilling wood boards. They clamp the wood board with a gripper and feed it onto a worktable, then use a drill bit and spindle to perform drilling and milling. They are one of the most important pieces of equipment in the woodworking industry.

[0003] With the rapid development of the furniture industry, the market demands increasingly higher precision from CNC drilling centers. CNC drilling equipment is the final step in the three major processing steps of panel furniture: cutting, edge banding, and drilling. Dimensional errors in the panels from cutting and edge banding accumulate in the drilling process, and there are also inherent dimensional errors in panel manufacturing. To ensure the precision of drilling and grooving, it is necessary to measure the dimensional errors of the panels before processing and compensate for them in the software to achieve good installation results. In the previous cutting process, the dimensions of the panels cannot be guaranteed to be 100% accurate, with an error of approximately 1mm. If processing is done directly in the CNC drilling process, the error between the hole position and the reference edge may be significant, making it impossible to guarantee the accuracy of the hole position relative to the reference edge. This can lead to misalignment between the two panels during assembly. Therefore, it is necessary to compensate for the error by measuring the actual dimensions of the panels to ensure the accuracy of the reference hole positions and avoid issues such as steps or misalignment during assembly. This also places higher demands on the precision of panel inspection. Existing technologies for detecting sheet metal dimensions mostly employ photoelectric sensors that input switching signals via I / O modules. However, the slow response of the I / O modules and the instability of the photoelectric sensors often lead to inaccurate detection. Furthermore, photoelectric sensors are highly sensitive to the color of the sheet metal; for light-colored sheets, the sensitivity decreases, resulting in unstable data and significantly reducing equipment stability. Therefore, enabling timely error compensation and data correction when processing workpieces with inaccurate dimensions to ensure processing quality is a technical problem that needs to be solved by those skilled in the art. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides an error compensation method for plate size detection, which solves the problems mentioned in the background section.

[0005] To achieve the above objectives, the present invention provides the following technical solution: an error compensation method for plate size detection, comprising a workpiece length detection system, a workpiece width detection system, and a workpiece thickness detection system;

[0006] For board length error compensation, except for holes positioned in the X+ direction, other holes exceeding half the board length require horizontal offset compensation. For example, assuming the board length is x, the hole's x-coordinate is x1, and the actual measured board length is x2, if x1 > x / 2, then X = x1 - (x - x2). For instance, if the board length in the processing file is 400mm, and a hole is machined 10mm from the left edge, the software defaults to starting machining from the right edge. If the actual board length is 398mm, without compensation, the machined hole will be 8mm from the left edge. This will create a step-like effect during board installation. Therefore, the software needs to perform error compensation to ensure the hole is 10mm from the left edge, transferring the error to the center of the board to ensure a good installation result.

[0007] The board width error compensation is based on the gripper mechanism side. When the distance to be processed exceeds half of the board width (y / 2), the overall Y-direction offset error value is compensated. That is, assuming the board width is y, the y-direction coordinate of the hole is y1, and the actual measured and calculated board width is y2, if y1>y / 2, then Y=y1-(y-y2). Assuming the board width of the processing file is 300mm, and a hole is processed at the bottom edge of the board 10mm away from the edge, the software defaults to starting processing from the top edge as the reference edge. If the actual board length detected at this time is 398mm, without compensation, the hole processed by the software will be 8mm away from the left edge. This situation will cause a step during the board installation process. Therefore, the software needs to perform error compensation to ensure that the hole is 10mm away from the left edge, transferring the error to the middle of the board to ensure that the board achieves a good installation effect.

[0008] Thickness error compensation includes three compensation methods. The first is the default method, which uses the lower edge of the board as a reference to ensure that the distance Z1 from the lower edge to the hole is consistent with the processing data. The second is compensation based on the upper edge, which offsets the processing in the horizontal and front directions in the Z direction to ensure that the distance Z2 from the upper edge to the hole is consistent with the processing data. The third is centering compensation, which can be used in conjunction with the first two methods. The processing in the horizontal direction is at the center of the thickness. Even if the actual thickness changes, it will remain at the center of the actual thickness to ensure that Z1 and Z2 are equal.

[0009] Furthermore, a positioning block is fixedly connected to the top surface of the worktable, a laser sensor is fixedly connected to the left side of the worktable via a bracket, a gripper mechanism that reciprocates horizontally along the guide rail is fixedly connected to the left side of the worktable, and a side-leaning mechanism that reciprocates horizontally along the crossbeam is fixedly connected to the right side of the worktable.

[0010] A cylinder is fixedly connected to the top of the gripper mechanism. The cylinder controls the gripper mechanism to grip and release the gripper mechanism through transmission. A magnetic scale and a reading head are fixedly connected to the gripper mechanism respectively. A servo motor is fixedly connected to the side of the side-mounted mechanism.

[0011] Furthermore, the workpiece length detection system includes a laser sensor, a servo driver, and a motion control card. The laser sensor and the servo driver are connected in a one-way control manner, and the servo driver and the motion control card are connected in parallel in a two-way control manner via an EtherCAT bus. The laser sensor is connected to the probe DI of the servo driver. The probe DI terminal is triggered by an external signal, and the MCU inside the servo driver triggers a high-speed external interrupt to record the servo axis position at the time of triggering. The precise position of the corresponding servo motor of the gripper mechanism 4 at the time of triggering is read through the EtherCAT bus, and corresponding calculations are performed. The probe function is the position latching function, which can latch the position information or command unit when the external probe DI signal or the servo motor Z signal changes.

[0012] The laser sensor is fixed above the worktable. Before processing, the gripper mechanism is first set at the origin of the positioning block, and this position is recorded as X0. Then, the gripper mechanism is set at the origin of the laser sensor. Generally, the gripper mechanism is moved along the linear guide along the X direction until the gripper just triggers the laser sensor signal, and this position is recorded as X1. The distance from the positioning block to the laser sensor is recorded as X2 = X0 - X1. When processing begins, the workpiece is fed to the worktable via the gripper mechanism using an EtherCAT bus and PDO. The change in the pulse value read from the servo drive register is recorded as N. Then, the position distance is calculated and converted through the electronic gear ratio. The conversion formula is: L=M / 100=(N / T) / 100, where M represents the number of pulses sent by the host computer, N represents the actual change in pulse value, T represents the electronic gear ratio, and L represents the distance moved by the mechanism. When the end of the board detaches from the laser sensor, a falling edge signal will be detected, triggering the probe function to record the distance X3 moved by the gripper mechanism at the time of triggering. Through automatic calculation, the length dimension of the board can be calculated by adding X2 and X3.

[0013] Furthermore, the workpiece width detection system includes a motion control card, a servo driver, a second servo motor, a position detection unit, and a position feedback unit. The servo driver and the motion control card are connected in parallel via bidirectional control through an EtherCAT bus, and the servo driver and the second servo motor are connected in series via bidirectional control.

[0014] When the gripper mechanism delivers the workpiece to the worktable, the second servo motor drives the side-mounted mechanism on the worktable to reciprocate horizontally and closely adhere to the workpiece. The motion control card reads whether the torque of the second servo motor reaches the set torque percentage via the EtherCAT bus. When the torque of the second servo motor reaches the set value, it indicates that the side-mounted mechanism has adhered to the workpiece. The position feedback device provides feedback on the position of the side-mounted mechanism at this time. The position of the side-mounted plate at this time is recorded as X4. Before processing, the origin of the position of the side-mounted mechanism is first set. Generally, the side-mounted mechanism is moved along the linear guide along the Y direction to a hard limit distance of 5-10mm. The gripper mechanism is moved to the position directly opposite the side-mounted plate. The distance between the gripper mechanism and the origin of the side-mounted mechanism is measured and recorded as X5. Through automatic calculation, the width dimension of the workpiece can be calculated by subtracting X4 from X5.

[0015] Furthermore, the workpiece thickness detection system includes a motion control card, a reading head, a magnetic scale, and a gripping mechanism. The motion control card and the reading head are connected in series for unidirectional control. The reading head and the magnetic scale are read through non-contact installation at a distance of 0.1-2mm. The gripping mechanism is fixedly connected to both the reading head and the magnetic scale. The gripping mechanism can clamp and release the workpiece via a cylinder drive. Simultaneously, when clamping the workpiece, the cylinder drives the magnetic scale. As the magnetic scale moves relative to the reading head, the magnetic marker causes the reading head to sense a change in the magnetic field. Sensors inside the reading head convert these magnetic field signals into electrical signals, which are then processed by a signal processing circuit.

[0016] When the gripper mechanism releases the plate, the release height is recorded as X6. When the gripper mechanism clamps the plate, the downward clamping distance is recorded as X7. Through automatic calculation, the thickness of the plate is calculated from X6 to X7. This method uses differential signal transmission, which provides strong anti-interference capability against external interference. During processing, the system can identify the position information of each magnetic mark and match it with a specific position. By detecting the displacement of the magnetic scale by the read head, the thickness of the plate can be calculated.

[0017] Furthermore, during processing, the presence of a workpiece can be detected by this laser sensor. If no workpiece is found, pressing the start button will trigger an alarm indicating that no workpiece is present, thus preventing other malfunctions.

[0018] The present invention has the following beneficial effects:

[0019] 1. By detecting and compensating for the length, width, and thickness of the sheet metal, the machining accuracy of the CNC drilling center can be improved, facilitating subsequent assembly of the sheet metal and improving the processing quality of the product.

[0020] 2. Laser sensors can detect whether there is a sheet material on the processing surface, which can prevent damage to the CNC drilling center equipment in case of operator error.

[0021] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the workpiece length detection system of the present invention before processing;

[0024] Figure 2 For the present invention Figure 1 A magnified view of a section at point A in the middle;

[0025] Figure 3 This is a schematic diagram of the gripper mechanism of the present invention;

[0026] Figure 4 This is a schematic diagram of the reading head and magnetic scale of the present invention;

[0027] Figure 5 This is a schematic diagram of the side-support mechanism of the present invention;

[0028] Figure 6 This is a schematic diagram showing the position X0 of the gripper mechanism of the present invention at the origin of the positioning block;

[0029] Figure 7 This is a schematic diagram of position X1 where the gripper mechanism of the present invention just triggers the laser sensor signal;

[0030] Figure 8 This is a schematic diagram showing the distance X2 from the positioning block to the laser sensor in this invention;

[0031] Figure 9 This is a schematic diagram of the plate length error compensation of the present invention;

[0032] Figure 10 This is a schematic diagram showing the length dimensions of the plate of the present invention;

[0033] Figure 11 This is a schematic diagram (X4) showing the position of the side support plate of the present invention;

[0034] Figure 12 This is a schematic diagram showing the distance X5 between the gripper mechanism and the origin of the side-mounted mechanism of the present invention;

[0035] Figure 13 This is a schematic diagram of the plate width error compensation structure of the present invention;

[0036] Figure 14 This is a schematic diagram showing the height X6 of the gripper release point according to the present invention;

[0037] Figure 15 This is a schematic diagram showing the downward clamping distance X7 of the clamping hand in this invention;

[0038] Figure 16 The thickness error compensation of this invention includes three compensation methods;

[0039] Figure 17 This is a schematic block diagram illustrating the control connections of each structure in this invention.

[0040] The attached diagram lists the components represented by each number as follows:

[0041] In the diagram: 1-Workbench, 2-Positioning block, 3-Laser sensor, 4-Hand clamping mechanism, 5-Side leaning mechanism, 41-Cylinder, 42-Magnetic scale, 43-Reading head, 44-Servo motor one, 51-Servo motor two. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] Please see Figures 1-17 The present invention provides a technical solution: an error compensation method for plate size detection, including a workpiece plate length detection system, a workpiece plate width detection system and a workpiece plate thickness detection system;

[0044] For plate length error compensation, except for holes positioned in the horizontal direction, other holes exceeding half the plate length require offset compensation in the X direction. That is, assuming the plate length is x, the hole's X-coordinate is x1, and the actual measured plate length is x2, if x1 > x / 2, then X = x1 - (x - x2). Figure 9 As shown, assuming the length of the processing board is 400mm, a hole is machined on the left edge of the board, 10mm from the edge. The software defaults to starting processing from the right side as the reference edge. If the actual board length detected at this time is 398mm, without compensation, the hole machined by the software will be 8mm from the left edge. This will cause a step in the installation process. Therefore, the software needs to perform error compensation to ensure that the hole is 10mm from the left edge, transferring the error to the middle of the board to ensure that the board achieves a good installation effect.

[0045] Plate width error compensation is based on the four sides of the gripper mechanism. When the distance to be processed exceeds half the plate width (y / 2), the overall Y-direction offset error is compensated. That is, assuming the plate width is y, the y-direction coordinate of the hole position is y1, and the actual measured and calculated plate width is y2, if y1 > y / 2, then Y = y1 - (y - y2). Figure 13 As shown, assuming the width of the processing board is 300mm, a hole is machined at the bottom edge of the board, 10mm from the edge. The software defaults to starting processing from the top edge as the reference edge. If the actual board length detected at this time is 398mm, without compensation, the hole machined by the software will be 8mm from the left edge. This will cause a step in the installation process. Therefore, the software needs to perform error compensation to ensure that the hole is 10mm from the left edge, transferring the error to the middle of the board to ensure a good installation effect.

[0046] Plate thickness error compensation includes three compensation methods, such as... Figure 16 As shown, the first method is the default method, which does not perform compensation. It uses the lower edge of the board as the reference to ensure that the distance Z1 from the lower edge to the hole is consistent with the processing data. The second method uses the upper edge as the reference and performs offset compensation in the Z direction for the processing in the horizontal and front directions to ensure that the distance Z2 from the upper edge to the hole is consistent with the processing data. The third method maintains the center compensation. The third compensation rule is used in conjunction with the first and second compensation methods. Theoretically, the processing in the horizontal direction is at the center of the thickness. Even if the actual board thickness changes, it will still remain at the center of the actual thickness, ensuring that Z1 and Z2 are equal.

[0047] When machining components such as Ramino, Lock & Lock, and straighteners, it is essential to ensure the depth of the slots or holes for proper assembly. Otherwise, the components may protrude or fail to assemble. Therefore, when machining the lower surface of a sheet, to ensure correct assembly of the component into the machined slots or holes, the distance from the lower edge to the hole must match the machining data. This requires the first compensation method, using the lower edge of the sheet as a reference. When machining the upper surface of a sheet, the same applies. The second compensation method, using the upper edge of the sheet as a reference, is needed to ensure correct assembly. To ensure uniform and aesthetically pleasing hole positions without affecting assembly, a third compensation method, maintaining centering, can be chosen.

[0048] Among them, such as Figure 1As shown, a positioning block 2 is fixedly connected to the top surface of the workbench 1, a laser sensor 3 is fixedly connected to the left side of the workbench 1 via a bracket, a gripping mechanism 4 that reciprocates horizontally along the guide rail is fixed to the left side of the workbench 1, and a side-leaning mechanism 5 that reciprocates horizontally along the crossbeam is fixedly connected to the right side of the workbench 1.

[0049] like Figure 3-4 As shown, a cylinder 41 is fixedly connected to the top of the gripper mechanism 4. The cylinder 41 controls the gripper mechanism 4 to grip and release the object via a transmission. The gripper mechanism 4 is fixedly connected to a magnetic scale 42, a reading head 43, and a servo motor 44, respectively. Figure 5 As shown, a servo motor 51 is fixedly connected to the side of the side-mounted mechanism 5.

[0050] The workpiece length detection system includes a laser sensor 3, a servo driver, and a motion control card. The laser sensor 3 is connected to the servo driver in a one-way control connection, and the servo driver and the motion control card are connected in parallel in a two-way control connection via an EtherCAT bus. The laser sensor 3 is connected to the probe DI of the servo driver. The probe DI terminal is triggered by an external signal, and the MCU inside the servo driver triggers a high-speed external interrupt to record the servo axis position at the time of triggering. The precise position of the corresponding servo motor 44 of the gripper mechanism 4 at the time of triggering is read through the EtherCAT bus, and corresponding calculations are performed. The probe function is the position latching function, which can latch the position information or command unit when the external probe DI signal or the servo motor Z signal changes.

[0051] Laser sensor 3 is fixed above worktable 1. Before processing, gripper mechanism 4 is first set at the origin of positioning block 2. The position of gripper mechanism 4 at this time is recorded as X0. Figure 6 As shown, the gripper mechanism 4 is then positioned at the origin of the laser sensor 3. Typically, the gripper mechanism 4 is moved along the linear guide rail in the X direction until the gripper just triggers the signal from the laser sensor 3. The position of the gripper mechanism 4 at this point is denoted as X1. Figure 7 As shown, the distance from positioning block 2 to laser sensor 3 is denoted as X2 = X0 - X1, as follows. Figure 8 As shown, at the start of processing, when the workpiece is fed to the worktable 1 via the gripper mechanism 4, the EtherCAT bus is used. The change in pulse value of the servo driver register is read via the PDO address and recorded as N. Then, the position distance is calculated and converted using the electronic gear ratio. The conversion formula is: L=M / 100=(N / T) / 100. The host computer software is set to move the mechanism 1mm when 100 pulse values ​​are set. M represents the number of pulses sent by the host computer, N represents the actual pulse value change, T represents the electronic gear ratio, and L represents the distance moved by the mechanism. When the end of the workpiece is removed from the laser sensor 3, a falling edge signal will be detected, triggering the probe function to record the distance X3 moved by the gripper mechanism 4 at the time of triggering. Through automatic calculation, the length dimension of the workpiece can be calculated by adding X2 and X3. Figure 10 As shown.

[0052] The workpiece width detection system includes a motion control card, a servo driver, a servo motor 51, a position detection unit, and a position feedback unit. The servo driver and the motion control card are connected in parallel via bidirectional control through an EtherCAT bus, and the servo driver and the servo motor 51 are connected in series via bidirectional control.

[0053] When the gripper mechanism 4 delivers the workpiece to the worktable 1, servo motor 2 51 drives the side-mounting mechanism 5 on the worktable 1 to reciprocate horizontally, closely adhering to the workpiece. The motion control card reads whether the torque of servo motor 2 51 has reached the set torque percentage via the EtherCAT bus. When the torque of servo motor 2 51 reaches the set value, it indicates that the side-mounting mechanism 5 has adhered to the workpiece. The position feedback device provides feedback on the current position of the side-mounting mechanism 5. The position of the side-mounting plate at this time is recorded as X4. Figure 11 As shown, before processing, first set the origin of the side-mounting mechanism 5. Generally, move the side-mounting mechanism 5 along the linear guide rail in the Y direction to a distance of 5-10mm from the hard limit. Move the gripper mechanism to the position directly opposite the side plate, and measure the distance between the gripper mechanism and the origin of the side-mounting mechanism 5, denoted as X5. Figure 12 As shown, the width dimension of the board can be calculated by automatically calculating X4-X5.

[0054] The workpiece thickness detection system includes a motion control card, a reading head 43, a magnetic scale 42, a gripping mechanism 4, and a servo motor 44. The motion control card is connected in series with the reading head 43 for unidirectional control. The reading head 43 and the magnetic scale 42 are read through non-contact installation with an installation distance of 0.1-2mm. The gripping mechanism 4 is fixedly connected to both the reading head 43 and the magnetic scale 42. The gripping mechanism 4 is driven by a cylinder 41 to clamp and release the workpiece. Simultaneously, when clamping the workpiece, the cylinder 41 drives the magnetic scale 42. When the magnetic scale 42 moves relative to the reading head 43, the magnetic mark causes the reading head 43 to sense the change in the magnetic field. The sensor inside the reading head 43 converts these magnetic field signals into electrical signals, which are then processed by the signal processing circuit.

[0055] When the gripper mechanism 4 releases the plate, the height to which the gripper mechanism 4 releases is recorded as X6. Figure 14 As shown, when the gripper mechanism 4 clamps the plate, the downward clamping distance of the gripper mechanism 4 is recorded as X7. Figure 15 As shown, the thickness of the plate is calculated automatically from X6-X7. This method uses differential signal transmission, which provides strong anti-interference capability against external interference. During processing, the system can identify the position information of each magnetic mark and match it with a specific position. By detecting the displacement of the magnetic scale 42 through the read head 43, the thickness of the plate can be calculated.

[0056] During processing, the laser sensor can detect the presence of a workpiece. If no workpiece is found, pressing the start button will trigger an alarm indicating that no workpiece is present, thus preventing other malfunctions.

[0057] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An error compensation method for sheet metal dimension detection, based on a worktable (1), a workpiece length detection system, a workpiece width detection system, and a workpiece thickness detection system; characterized in that: Includes the following steps: Calculate the length of the board and compensate for errors in the length. Assume the length of the board is x, the coordinate of the hole in the x-direction is x1, and the actual measured and calculated length of the board is x2. Except for the holes located in the horizontal direction, if other holes exceed x / 2 of the length of the board, offset compensation is performed in the X direction. That is, set the length of the board to x, the coordinate of the hole in the x-direction to x1, and the actual measured and calculated length of the board to x2. If x1>x / 2, X=x1-(x-x2). Calculate the width of the plate and compensate for the error of the plate width: Assume that the plate width is y, the y-direction coordinate of the hole position is y1, and the actual measured and calculated plate width is y2. Correct it based on the clamping mechanism (4) side. When the distance to be processed exceeds half of the plate width y / 2, compensate for the overall Y-direction offset error value. That is, set the plate width to y, the y-direction coordinate of the hole position to y1, and the actual measured and calculated plate width to y2. If y1>y / 2, then Y=y1-(y-y2). The thickness of the sheet metal is calculated, and error compensation is performed. Thickness error compensation includes three methods: The first method uses the lower edge of the sheet metal as a reference, ensuring the distance Z1 from the lower edge to the hole is consistent with the machining data; the second method uses the upper edge as a reference, compensating for the offset of machining processes in the horizontal and front directions in the Z direction, ensuring the distance Z2 from the upper edge to the hole is consistent with the machining data; the third method maintains centering compensation, using the first and second methods in conjunction, ensuring the horizontal machining process is at the center of the thickness, and even after changes in the actual sheet thickness, it remains at the center of the actual thickness, ensuring Z1 and Z2 are equal. Among them, a positioning block (2) is fixedly connected to the top surface of the workbench (1), a laser sensor (3) is fixedly connected to the left side of the workbench (1) via a bracket, a gripper mechanism (4) that moves horizontally back and forth along the guide rail is fixedly connected to the left side of the workbench (1), and a side-leaning mechanism (5) that moves horizontally back and forth along the crossbeam is fixedly connected to the right side of the workbench (1). The top of the gripping mechanism (4) is fixedly connected to a cylinder (41), and the gripping mechanism (4) is fixedly connected to a magnetic grid ruler (42) and a reading head (43). The side of the side-mounted mechanism (5) is fixedly connected to a servo motor (51). The workpiece length detection system includes a laser sensor (3), a servo driver and a motion control card. The laser sensor (3) is connected to the servo driver in a one-way control connection, and the servo driver and the motion control card are connected in parallel in a two-way control connection via an EtherCAT bus. The laser sensor (3) is connected to the probe DI of the servo driver. The probe DI terminal is triggered by an external signal. The MCU inside the servo driver triggers a high-speed external interrupt, records the servo axis position at the time of triggering, reads the precise position of the corresponding servo motor (44) of the gripper mechanism (4) at the time of triggering via an EtherCAT bus, and performs corresponding calculations. The probe function is the position latching function, which is used to latch the position information or instruction unit when the external probe DI signal or the servo motor Z signal changes. The laser sensor (3) is fixed above the worktable (1). Before processing, the gripper mechanism (4) is first set at the origin of the positioning block (2). The position of the gripper mechanism (4) is recorded as X0. Then, the gripper mechanism (4) is set at the origin of the laser sensor (3). The gripper mechanism (4) is moved along the linear guide along the X direction to the point where the gripper triggers the signal of the laser sensor (3). The position of the gripper mechanism (4) is recorded as X1. The distance from the positioning block (2) to the laser sensor (3) is recorded as X2 = X0 - X1. When processing begins, the plate is sent to the worktable (1) through the gripper mechanism (4). Eth The erCAT bus reads the pulse value change of the servo driver register through the PDO address and records it as N. Then, it is converted into position distance through electronic gear ratio calculation. The conversion formula is: L=M / 100=(N / T) / 100, where M represents the number of pulses sent by the host computer, N represents the actual pulse value change, T represents the electronic gear ratio, and L represents the distance moved by the mechanism. When the end of the board is separated from the laser sensor (3), a falling edge signal will be detected, triggering the probe function to record the distance X3 moved by the gripper mechanism (4) at the time of triggering. Through automatic calculation, X2+X3 is calculated as the length dimension of the board, i.e., the board length.

2. The error compensation method for plate size detection according to claim 1, characterized in that, The workpiece width detection system includes a motion control card, a servo driver, a second servo motor (51), a position detection unit and a position feedback unit. The servo driver and the motion control card are connected in parallel via bidirectional control through an EtherCAT bus, and the servo driver and the second servo motor (51) are connected in series via bidirectional control. When the gripper mechanism (4) delivers the plate to the worktable (1), the servo motor (51) drives the side-mounted mechanism (5) on the worktable (1) to move horizontally and reciprocally to fit the plate. The motion control card reads whether the torque of the servo motor (51) reaches the set torque percentage through the EtherCAT bus. When the torque of the servo motor (51) reaches the set value, it means that the side-mounted mechanism (5) has been attached to the plate. The position feedback device feeds back the position of the side-mounted mechanism (5) at this time. The position of the side plate at this time is recorded as X4. Before processing, the position origin of the side-mounted mechanism (5) is set first. The side-mounted mechanism (5) is moved along the linear guide along the Y direction to a distance of 5-10mm from the hard limit. The gripper mechanism is moved to the position directly opposite the side plate. The distance between the gripper mechanism and the origin of the side-mounted mechanism (5) is measured and recorded as X5. Through automatic calculation, X4-X5 is calculated as the width dimension of the plate, i.e., the plate width.

3. The error compensation method for plate size detection according to claim 2, characterized in that, The workpiece thickness detection system includes a motion control card, a reading head (43), a magnetic scale (42), and a gripping mechanism (4). The motion control card and the reading head (43) are connected in series for one-way control. The reading head (43) and the magnetic scale (42) are read through non-contact installation. The gripping mechanism (4) is fixedly connected to the reading head (43) and the magnetic scale (42) respectively. The gripping mechanism (4) can clamp and release the workpiece by being driven by the cylinder (41). At the same time, when clamping the workpiece, the cylinder (41) of the gripping mechanism (4) will drive the magnetic scale (42) to move. When the magnetic scale (42) moves relative to the reading head (43), the magnetic mark makes the reading head (43) sense the change in the magnetic field. The sensor inside the reading head (43) converts the magnetic field signal into an electrical signal, which is then processed by the signal processing circuit. When the clamping mechanism (4) releases the plate, the height at which the clamping mechanism (4) releases is recorded as X6. When the clamping mechanism (4) clamps the plate, the distance at which the clamping mechanism (4) clamps downward is recorded as X7. Through automatic calculation, the thickness of the plate is calculated from X6-X7, i.e., the plate thickness.

4. The error compensation method for plate size detection according to claim 3, characterized in that, During processing, the laser sensor is also used to detect whether there is a board on the worktable (1). When there is no board, pressing the start button will trigger an alarm indicating that there is no board, thus preventing other malfunctions.

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