A laser cutting automatic control method and system based on a servo motor

Abstract

The application discloses a kind of laser cutting automatic control method and system based on servo motor, record when cutting position X axis absolute value encoder reading, and set the position limit of laser head in X axis direction, control X axis side servo motor completes cutting positioning;Control Y axis servo motor so that laser head moves to the cutting starting point of transmission material edge portion, open laser and cutting gas, laser head moves at specified cutting speed along Y axis uniform speed and cuts transmission material, when laser head moves to cutting end point, cutting is completed and laser and cutting gas are closed;After cutting is completed, laser head returns to cutting starting point at Y axis with the change speed of first fast then slow, when zero position limit switch appears rising edge signal, carry out laser head in the automatic zero point correction of Y axis direction.The application can solve the accurate positioning problem of each direction axis in laser cutting process.

Description

Technical Field

[0001] This invention relates to the field of industrial automation technology, and in particular to an automatic control method and system for laser cutting based on a servo motor. Background Technology

[0002] With the rapid development of the processing industry, laser cutting machines have been used more and more widely. They can achieve fast, accurate and efficient cutting of metal materials such as stainless steel, carbon steel, aluminum plates, galvanized plates, and iron plates.

[0003] In laser cutting machines, the positioning requirements for axes in all directions are extremely high. For example, in the length direction of cutting steel plates, the positioning accuracy needs to reach 0.05% of the cutting length. If cutting a 6m long steel plate, the positioning accuracy for the cutting length must be within 3mm. The accuracy requirements in the cutting height direction are even higher, requiring a positioning accuracy within 0.01mm. This places very high demands on the positioning execution equipment. Servo motors, due to their high positioning accuracy, are very suitable for use in the positioning execution equipment of laser cutting machines.

[0004] A servo motor is a motor used in servo systems to control the movement of mechanical components. Servo motors can control speed and position with extremely high accuracy, making them suitable as actuators in automatic control systems. They also possess characteristics such as a small electromechanical time constant and high linearity. A servo motor enables the output controlled variables, such as the position, orientation, and state of an axis, to follow arbitrary changes in the input target (or given value). Servo motors primarily rely on pulses for positioning. The PLC (Programmable Logic Controller) sends speed pulses to the servo amplifier, which controls the servo motor to rotate at a specified speed. The motor's rotation is converted into linear displacement of the axis through gears and a lead screw, thus achieving axis positioning. The servo motor also incorporates a pulse encoder, which emits a corresponding number of pulses for each rotation angle, transmitting them back to the PLC controller. This forms a closed-loop control system with the pulses received by the servo motor, enabling accurate control of the motor's rotation and achieving precise positioning accuracy of 0.01mm or even higher, fully meeting the positioning accuracy requirements of laser cutting.

[0005] Because there is a certain error in the width data of the cutting plate, in order to ensure that the cutting plate can be completely cut, the laser and cooling gas need to be started in advance before the laser head reaches the edge of the cutting plate; similarly, after the cutting plate is cut, even though the laser head has already moved beyond the other side of the cutting plate, the laser and cooling gas should still be kept on for a short period of time.

[0006] The servo motor in the cutting direction (the width direction of the steel plate) converts the motor rotation into displacement on the linear guide rail through a gear and lead screw device. When the gear and lead screw mesh, there is an unavoidable gap. Each time a cut is made, the measurement reading of the absolute encoder will have a small offset. After multiple cuts, it becomes a large error, and it is necessary to find a way to eliminate the accumulated error. Summary of the Invention

[0007] The main objective of this invention is to provide an automatic control method and system for laser cutting based on a servo motor, which can solve the problem of accurate positioning of axes in various directions during laser cutting.

[0008] The technical solution adopted in this invention is: an automatic control method for laser cutting based on a servo motor, used to control the movement of a laser cutting unit. The laser cutting unit includes a laser head, which is connected to a Y-axis along the width direction of the conveyed material. The laser head moves along the Y-axis via a Y-axis servo motor. The two ends of the Y-axis are set on an X-axis along the material conveying direction. The X-axis servo motor drives the entire Y-axis to move along the X-axis. The X-axis servo motor and the Y-axis servo motor are respectively equipped with an X-axis absolute encoder and a Y-axis absolute encoder. This method includes the following steps:

[0009] S1. Record the X-axis absolute encoder reading when in the cutting position, set the laser head position limit in the X-axis direction, and control the X-axis servo motor to complete the cutting positioning;

[0010] S2. Control the Y-axis servo motor to move the laser head to the cutting start point at the edge of the conveyed material, turn on the laser and cutting gas, and the laser head moves at a specified cutting speed along the Y-axis to cut the conveyed material. When the laser head moves to the cutting end point, the cutting is completed and the laser and cutting gas are turned off.

[0011] S3. After the cutting is completed, the laser head returns to the cutting starting point along the Y-axis at a speed that changes from fast to slow. The cutting starting point is equipped with a zero-point limit switch. When the zero-point limit switch generates a rising edge signal, the laser head performs automatic zero-point correction in the Y-axis direction.

[0012] According to the above scheme, in step S1, the X-axis absolute encoder reading is recorded at the cutting position, and the position limit of the laser head in the X-axis direction is set, specifically as follows:

[0013] The positional relationship between the cutting position and the drive roller used for material transfer is determined. The laser head is moved along the X-axis to the cutting position by controlling the X-axis servo motor. Then, the position value of the X-axis absolute encoder is recorded as the cutting position value, denoted as P. X，Cut ;

[0014] Based on the distance between the drive rollers and the roller diameter, the range in which the laser head can move back and forth along the X-axis at the cutting position is calculated, and a preset margin is left to obtain the X-axis position limit value; if the calculated cutting position setting value exceeds the X-axis position limit value, an alarm is triggered and the cutting step is stopped.

[0015] According to the above scheme, in step S1, controlling the X-axis servo motor to complete the cutting positioning is specifically as follows:

[0016] A distance sensor is installed at the outlet of the cutting machine to collect the distance from the head of the conveyed material to the cutting position. Based on the length of the conveyed material collected by the distance sensor, the position setpoint of the cutting position is calculated and denoted as P. X，Set Preset a small range of X-axis values ​​P A，X As the range of arrival, let P be... X，Act For the actual position of the cutting position, when |P X，Set -P X，Act |≤P A，X When the time indicates that the position is reached, the X-axis servo motor stops moving; if |P X，Set -P X，Act |>P A，X The proportional controller is then used to calculate the setpoint for the X-axis servo motor's movement speed and apply a limit, as shown in the following formula:

[0017] V ServoX，Set =LIM X [K P，X ×(P X，Set -P X，Act )]

[0018] In the formula, V ServoX，Set LIM sets the moving speed of the X-axis servo motors on both sides. X K represents the limiting element for the X-axis velocity. P，X This is the proportional coefficient of the X-axis proportional controller.

[0019] According to the above scheme, in step S2, controlling the Y-axis servo motor to move the laser head to the cutting starting point at the edge of the conveyed material is specifically as follows:

[0020] As the laser head moves along the Y-axis to the edge of the conveyed material, the set position value of the cutting start point is based on the edge position of the conveyed material calculated according to the width data, minus twice the maximum width error.

[0021] Preset a small range of Y-axis values ​​P A，Y As the positioning range, when the difference between the actual position of the laser head on the Y-axis and the set position of the cutting starting point is outside the positioning range, the speed setting value for the first positioning on the Y-axis is calculated using the following formula:

[0022] V ServoY，Set1=LIM Y [K P，Y ×(P Y，Set1 -P Y，Act )]

[0023] In the formula, LIM Y K represents the limiting element for the Y-axis velocity. P，Y P is the scaling factor for the Y-axis. Y，Act P represents the actual position of the laser head on the Y-axis. Y，Set1 This is the set position value of the cutting start point when the laser head is first positioned.

[0024] According to the above scheme, in step S3, after the cutting is completed, the laser head returns to the cutting starting point along the Y-axis at a varying speed, specifically as follows:

[0025] After the cutting is completed, the Y-axis servo motor is controlled to move towards the cutting starting point at a preset high speed, and the acceleration is also set to a preset high value.

[0026] When the laser head moves close to the cutting start point, the running speed is reduced, and the deceleration is set to a preset low value;

[0027] When the laser head moves to a certain small range from the cutting start point, it moves towards the cutting start point at a preset slow speed.

[0028] According to the above scheme, in step S3, when the zero-point limit switch generates a rising edge signal, automatic zero-point calibration of the laser head in the Y-axis direction is performed, specifically as follows:

[0029] When the zero-point limit switch shows a rising edge signal, it indicates that the laser head has moved to the cutting start point. Record the reading of the Y-axis absolute encoder at the current moment and use this reading as the new cutting start point position value. At the same time, set the speed of the Y-axis servo motor to zero and set the deceleration to a preset high value so that the Y-axis servo motor stops as soon as possible.

[0030] An automatic control system for laser cutting based on a servo motor is disclosed. The system includes a laser cutting unit, a controller, and a distance sensor installed at the cutting machine exit to collect the distance from the material head to the cutting position.

[0031] The laser cutting unit includes a laser head connected to a Y-axis along the width of the conveyed material. The laser head moves along the Y-axis via a Y-axis servo motor. The two ends of the Y-axis are positioned on an X-axis along the material conveying direction. An X-axis servo motor drives the entire Y-axis to move along the X-axis. The X-axis servo motor and the Y-axis servo motor are respectively equipped with an X-axis absolute encoder and a Y-axis absolute encoder. The two ends of the Y-axis are respectively located at the edge of the conveyed material, forming a cutting start point and a cutting end point.

[0032] The controller is used to execute the controller program to complete the steps of the servo motor-based automatic control method for laser cutting.

[0033] The distance sensor is a length grating.

[0034] The controller mentioned is a PLC controller.

[0035] A computer-readable storage medium having a controller program stored thereon, wherein the controller program, when executed by a controller, implements the steps of the aforementioned automatic control method for laser cutting based on a servo motor.

[0036] The beneficial effects of this invention are:

[0037] By setting synchronous X-axis servo motors at both ends of the X-axis, the entire Y-axis is controlled to move along the X-axis near the cutting position to accurately compensate for the positioning error of the transmission rollers; the Y-axis servo motor is controlled to position itself near one edge of the width direction of the conveyed material, the cutting gas and laser are turned on in advance, and it moves at a constant speed to the other side of the width direction of the conveyed material, and the cutting gas and laser are turned off after a delay to ensure that the conveyed material is completely cut; after cutting, the Y-axis servo motor returns to the cutting starting point at a speed that changes from fast to slow, and automatically corrects itself at the zero-position limit switch; this invention solves the problem of accurate positioning of axes in each direction during laser cutting, solves the problem of cumulative error generated during the movement of the Y-axis servo motor, realizes high-precision automated control of laser cutting, greatly reduces the labor intensity of workers, and improves the efficiency of the laser cutting process. Attached Figure Description

[0038] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0039] Figure 1 This is a flowchart of a method according to an embodiment of the present invention.

[0040] Figure 2 This is a schematic diagram of the system structure according to an embodiment of the present invention.

[0041] In the diagram: 1-Controller, 2-Servo amplifier, 3-First X-axis servo motor, 4-X-axis absolute encoder, 5-First X-axis, 6-Steel plate, 7-Front drive roller, 8-Rear drive roller, 9-Cut machine frame, 10-Y-axis, 11-Laser head, 12-Y-axis servo motor, 13-Y-axis absolute encoder, 14-Length grating, 15-Zero limit switch, 16-Second X-axis servo motor, 17-Second X-axis. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0043] This embodiment uses the transmission and cutting of steel plates as an example to further illustrate the present invention.

[0044] like Figure 2 As shown, this embodiment provides an automatic control system for laser cutting based on a servo motor, including a laser cutting unit, a controller 1, and a distance sensor installed at the cutting machine exit to collect the distance from the head of the steel plate 6 to the cutting position. In this embodiment, the distance sensor is a length grating 14, which is installed downstream of the cutting position between the cutting position and the transmission exit, and the distance between the starting point of the length grating and the cutting position is known.

[0045] The laser cutting unit includes a laser head 11, which is connected to a Y-axis 10 along the width of the conveyed material. The laser head 11 moves along the Y-axis 10 via a Y-axis servo motor 12. The two ends of the Y-axis 10 are positioned on an X-axis (i.e., a first X-axis 5 and a second X-axis 17) along the material conveying direction. Synchronous X-axis servo motors (i.e., a first X-axis servo motor 3 and a second X-axis servo motor 16) drive the entire Y-axis 10 to move along the X-axis. The first X-axis servo motor 3 and the Y-axis servo motor 12 are respectively equipped with an X-axis absolute encoder 4 and a Y-axis absolute encoder 13. The Y-axis 10 has a cutting start point and a cutting end point located at the edge of the conveyed material. For reinforcement, both the X-axis and Y-axis are mounted on the cutting machine frame 9.

[0046] In this embodiment, controller 1 is a PLC controller, which controls the first X-axis servo motor 3, the second X-axis servo motor 16, and the Y-axis servo motor 12 through servo amplifier 2 to complete the automatic control method for laser cutting based on servo motors. Figure 1 As shown, this method includes the following steps:

[0047] S1. Record the X-axis absolute encoder reading at the cutting position, set the laser head's position limit in the X-axis direction, and control the X-axis servo motor to complete the cutting positioning. Specifically:

[0048] Determine the positional relationship between the cutting position and the drive rollers used for material transfer, such as... Figure 2 As shown, in this embodiment, the cutting position is set at the exact midpoint between the front drive roller 7 and the rear drive roller 8. The laser head is moved along the X-axis to the cutting position by an X-axis servo motor, and the position value of the X-axis absolute encoder is recorded as the cutting position value, denoted as P. X，Cut .

[0049] Based on the distance between the drive rollers and the roller diameter, the range in which the laser head can move back and forth along the X-axis at the cutting position is calculated, and a preset margin is left to obtain the X-axis position limit value; if the calculated cutting position setting value exceeds the X-axis position limit value, an alarm is triggered and the cutting step is stopped.

[0050] In this embodiment, the distance between the front drive roller 7 and the rear drive roller 8 is 550mm, and the roller diameter is 180mm. The cutting position is located exactly in the middle of the two. Therefore, the roller can only move within a range of 185mm along the X-axis from the cutting position. If it exceeds this range, the laser will cut the drive roller, causing equipment damage. Considering leaving some margin, the final range of the X-axis movement is set to P. X，Cut Within ±130mm.

[0051] A distance sensor is installed at the outlet of the cutting machine to collect the distance from the head of the conveyed material to the cutting position. Based on the length of the steel plate 6 collected by the distance sensor, the position setting value of the cutting position is calculated and denoted as P. X，Set Preset a small range of X-axis values ​​P A，X In this embodiment, P is set as the positioning range. A，X =0.08mm. Let P be... X，Act For the actual position of the cutting position, when |P X，Set -P X，Act |≤P A，X When the time indicates that the position is reached, the X-axis servo motor stops moving; if |P X，set -P X，Act |>P A，X The proportional controller is then used to calculate the setpoint for the X-axis servo motor's movement speed and apply a limit, as shown in the following formula:

[0052] V ServoX，Set =LIM X [K P，X ×(P X，Set -P X，Act )]

[0053] In the formula, V ServoX，Set LIM sets the moving speed of the X-axis servo motors on both sides. X K represents the limiting element for the X-axis velocity. P，X This refers to the proportional coefficient of the X-axis proportional controller. In this embodiment, the speed limit range of the X-axis servo motor is 0.0 to 50.0 mm / s, and the proportional coefficient K... P，X =1.15. If |P X，set -P X，Act If the amplitude is large, the movement speed will be at its upper limit. As it approaches the set position, the speed will gradually decrease until it enters the positioning range, at which point the X-axis servo motor will stop.

[0054] S2. Control the Y-axis servo motor to move the laser head to the cutting start point at the edge of the conveyed material, turn on the laser and cutting gas, and the laser head moves uniformly along the Y-axis at a specified cutting speed to cut the conveyed material. When the laser head reaches the cutting end point, the cutting is completed, and the laser and cutting gas are turned off; specifically:

[0055] Because the width data of the steel plate has a certain margin of error, the position of the steel plate edge calculated based on the width data may not match the actual position. To ensure complete cutting of the steel plate, during the process of the laser head moving along the Y-axis to the edge of the conveying material, the set position value of the cutting starting point is calculated based on the edge position of the conveying material according to the width data, minus twice the maximum width error. In this embodiment, the position of the operating side edge of the steel plate calculated according to the width data is set as P. Y，OS The maximum error value for the width data is 40.0mm, so the initial positioning setting value for the Y-axis is P. Y，Set1 =P Y，OS -80.0mm.

[0056] Preset a small range of Y-axis values ​​P A，Y As the positioning range, when the difference between the actual position of the laser head on the Y-axis and the set position of the cutting starting point is outside the positioning range, the speed setting value for the first positioning on the Y-axis is calculated using the following formula:

[0057] V ServoY，Set1 =LIM Y [K P，Y ×(P Y，Set1 -P Y，Act )]

[0058] In the formula, LIM Y K represents the limiting element for the Y-axis velocity. P，Y P is the scaling factor for the Y-axis. Y，Act P represents the actual position of the laser head on the Y-axis. Y，Set1 This is the set position value of the cutting start point during the initial positioning of the laser head. In this embodiment, the range of the Y-axis is P. A，Y =0.1mm, the speed limit range of the Y-axis servo motor is 0.0~250.0mm / s, and the proportional coefficient K P，Y =2.0.

[0059] Before cutting, it is necessary to power on the laser, water chiller, laser head, and other laser-related equipment. The valve of the cutting gas cylinder must also be opened, and the laser must be allowed to reach its operating temperature range. Cutting can only begin once all laser-related equipment is fully started and ready for laser emission. Once all laser-related equipment is ready and the laser head has been initially positioned along the Y-axis (reaching P... Y，Set1First, turn on the cutting gas (the cutting gas cools the laser head and assists in cutting). After the cutting gas starts for 1 second, start the laser to emit light. The laser is emitted from the laser head nozzle and begins to cut the steel plate.

[0060] Simultaneously with the activation of the cutting gas, the Y-axis servo motor operates at the specified cutting speed V. Cutting Move from the operating side of the steel plate to the transmission side, that is:

[0061] V ServoY，set2 =V Cutting

[0062] In the formula, V ServoYset2 This is the speed setting for uniform movement (cutting) along the Y-axis. The position of the steel plate's transmission side edge, calculated based on the width data, is set as P. Y，DS The position setting after the Y-axis cutting is completed is P. Y，DS Adding twice the maximum width error, in this embodiment, the position setting value for the Y-axis cutting process is P. Y，Set2 =P Y，DS +80.0mm. When the laser head reaches the set value at its actual position on the Y-axis, it decelerates to zero and the laser is turned off. Wait 1 second after the laser is turned off before turning off the cutting gas.

[0063] S3. After cutting, the laser head returns to the cutting start point along the Y-axis at a speed that changes from fast to slow. A zero-point limit switch is installed at the cutting start point. When the zero-point limit switch generates a rising edge signal, automatic zero-point calibration of the laser head in the Y-axis direction is performed. The actual position of the laser head on the Y-axis is measured by a Y-axis absolute encoder. Using the zero-point limit switch on the operating side as the cutting start point, the laser head moves towards the transmission side, gradually increasing the position value. After cutting, the Y-axis needs to return to the cutting start point from the transmission side, awaiting the next cut.

[0064] Specifically:

[0065] After cutting is completed, the Y-axis servo motor is controlled to move towards the cutting starting point at a preset high speed, while the acceleration is also set to a preset high value; specifically, in this embodiment, when the actual position of the laser head on the Y-axis is greater than or equal to 200.0 mm, V is set... ServoY，Set3 =250mm / s, A Acc =A Dec =500mm / s 2 Among them, A Acc For the acceleration setpoint, A Dec This is the deceleration setting value.

[0066] When the laser head moves close to the cutting start point, the operating speed is reduced, and the deceleration is set to a preset low value, operating at a medium speed. Specifically, in this embodiment, when the actual position of the laser head on the Y-axis is between 20.0mm and 200.0mm, V ServoY，Set3 =80mm / s, A Acc =A Dec =300mm / s 2 .

[0067] When the laser head moves to a certain small range from the cutting start point, it moves towards the cutting start point at a preset slow speed. For example, in this embodiment, when the actual position of the Y-axis is less than 20.0mm, the V-axis is set... ServoY，Set3 =10mm / s, A Acc =A Dec =500mm / s 2 .

[0068] When the zero-point limit switch generates a rising edge signal, it indicates that the laser head has moved to the cutting start point. The current reading of the Y-axis absolute encoder is recorded and used as the new cutting start point position value. Simultaneously, the speed of the Y-axis servo motor is set to zero, and the deceleration is set to a preset high value to bring the Y-axis servo motor to a stop as quickly as possible. Specifically, V... ServoY，Set3 =0.0mm / s, A Acc =A Dec =500mm / s 2 This way, the Y-axis will automatically be corrected after each cut, preventing cumulative errors.

[0069] The laser cutting control method based on a servo motor provided in this invention first sets the X-axis movement range according to the site conditions and controls the X-axis to move to the set position; then, it controls the Y-axis to move to the vicinity of the operating edge of the steel plate, turns on the cutting gas and laser, and controls the Y-axis to move at a uniform cutting speed to outside the transmission edge of the steel plate, thus completing the steel plate cutting; then, the Y-axis returns to the initial zero position at a variable speed and is automatically corrected at the zero-position limit switch, thus completing one laser cutting process.

[0070] The servo motor-based automatic control method and system for laser cutting provided in this invention achieves fully automated control of laser cutting. Two servo motors are used to control the X-axis to move near the cutting position to precisely compensate for positioning errors of the transmission rollers; the Y-axis servo motor is positioned near the edge of the steel plate's operating side, the cutting gas and laser are turned on in advance, and the motor moves at a constant speed to the outside of the steel plate's transmission side edge, then the cutting gas and laser are turned off later to ensure the steel plate is completely cut; after cutting, the Y-axis servo motor returns to the zero position at a varying speed, and automatic correction is performed at the zero-position limit switch. Because the servo motor can achieve high-precision positioning of 0.01mm, it solves the problem of precise positioning of axes in all directions during laser cutting and the problem of cumulative errors generated during the movement of the Y-axis servo motor, achieving high-precision automated control of laser cutting, greatly reducing the labor intensity of workers and improving the efficiency of the laser cutting process.

[0071] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A laser cutting automatic control method based on a servo motor, used to control the movement of a laser cutting unit, characterized in that, The laser cutting unit includes a laser head connected to a Y-axis along the width of the conveyed material. The laser head moves along the Y-axis via a Y-axis servo motor. The two ends of the Y-axis are positioned on an X-axis along the material conveying direction, and are driven by synchronized X-axis servo motors to move the entire Y-axis along the X-axis. The X-axis and Y-axis servo motors are respectively equipped with X-axis absolute encoders and Y-axis absolute encoders. This method includes the following steps: S1. Record the X-axis absolute encoder reading when in the cutting position, set the laser head position limit in the X-axis direction, and control the X-axis servo motor to complete the cutting positioning; S2. Control the Y-axis servo motor to move the laser head to the cutting start point at the edge of the conveyed material, turn on the laser and cutting gas, and the laser head moves along the Y-axis at a specified cutting speed to cut the conveyed material at a uniform speed. When the laser head moves to the cutting end point, the cutting is completed and the laser and cutting gas are turned off. S3. After the cutting is completed, the laser head returns to the cutting starting point along the Y-axis at a speed that changes from fast to slow. The cutting starting point is equipped with a zero-point limit switch. When the zero-point limit switch generates a rising edge signal, the laser head performs automatic zero-point correction in the Y-axis direction. In step S1, the X-axis absolute encoder reading is recorded at the cutting position, and the position limit of the laser head in the X-axis direction is set, specifically as follows: The positional relationship between the cutting position and the drive roller used for material transfer is determined. The laser head is moved along the X-axis to the cutting position by the X-axis servo motor. The position value from the X-axis absolute encoder is then recorded as the cutting position value, denoted as [value missing]. ; Based on the distance between the drive rollers and the roller diameter, the range of movement of the laser head along the X-axis at the cutting position is calculated, and a preset margin is left to obtain the X-axis position limit value; if the calculated cutting position setting value exceeds the X-axis position limit value, an alarm is triggered and the cutting step is stopped. In step S1, the X-axis servo motor is controlled to complete the cutting positioning, specifically as follows: A distance sensor is installed at the outlet of the cutting machine to collect the distance from the head of the conveyed material to the cutting position. Based on the length of the conveyed material collected by the distance sensor, the position setpoint of the cutting position is calculated and denoted as [value missing]. Preset a small range of values ​​for the X-axis. As for the scope of arrival, record For the actual position of the cutting position, when When the time indicates that the position is reached, the X-axis servo motor stops moving; if The proportional controller is then used to calculate the setpoint for the X-axis servo motor's movement speed and apply a limit, as shown in the following formula: In the formula, The set values ​​for the moving speed of the X-axis servo motors on both sides. The limiting element representing the X-axis velocity. This is the proportional coefficient of the X-axis proportional controller.

2. The automatic control method for laser cutting based on a servo motor according to claim 1, characterized in that, In step S2, controlling the Y-axis servo motor causes the laser head to move to the cutting starting point at the edge of the conveyed material, specifically: As the laser head moves along the Y-axis to the edge of the conveyed material, the set position value of the cutting start point is based on the edge position of the conveyed material calculated according to the width data, minus twice the maximum width error. Preset a small range of Y-axis values As the positioning range, when the difference between the actual position of the laser head on the Y-axis and the set position of the cutting starting point is outside the positioning range, the speed setting value for the first positioning on the Y-axis is calculated using the following formula: In the formula, The limiting element represents the Y-axis velocity. The scaling factor for the Y-axis. This represents the actual position of the laser head on the Y-axis. This is the set position value of the cutting start point when the laser head is first positioned.

3. The automatic control method for laser cutting based on a servo motor according to claim 1, characterized in that, In step S3, after the cutting is completed, the laser head returns to the cutting starting point along the Y-axis at a varying speed, specifically: After the cutting is completed, the Y-axis servo motor is controlled to move towards the cutting starting point at a preset high speed, and the acceleration is also set to a preset high value. When the laser head moves close to the cutting start point, the running speed is reduced, and the deceleration is set to a preset low value; When the laser head moves to a certain small range from the cutting start point, it moves towards the cutting start point at a preset slow speed.

4. The automatic control method for laser cutting based on a servo motor according to claim 1, characterized in that, In step S3, when a rising edge signal appears on the zero-point limit switch, automatic zero-point calibration of the laser head in the Y-axis direction is performed, specifically as follows: When the zero-point limit switch shows a rising edge signal, it indicates that the laser head has moved to the cutting start point. Record the reading of the Y-axis absolute encoder at the current moment and use this reading as the new cutting start point position value. At the same time, set the speed of the Y-axis servo motor to zero and set the deceleration to a preset high value so that the Y-axis servo motor stops as soon as possible.

5. A laser cutting automatic control system based on a servo motor, characterized in that, This system includes a laser cutting unit, a controller, and a distance sensor installed at the cutting machine exit to collect the distance from the material head to the cutting position; among which, The laser cutting unit includes a laser head connected to a Y-axis along the width of the conveyed material. The laser head moves along the Y-axis via a Y-axis servo motor. The two ends of the Y-axis are located on an X-axis along the material conveying direction, and are driven to move along the X-axis by synchronous X-axis servo motors. The X-axis and Y-axis servo motors are equipped with X-axis absolute encoders and Y-axis absolute encoders, respectively. The two ends of the Y-axis are respectively located at the edge of the conveyed material, forming a cutting start point and a cutting end point. The controller is used to execute a controller program to complete the steps of the automatic control method for laser cutting based on a servo motor as described in any one of claims 1 to 4.

6. The automatic laser cutting control system based on a servo motor according to claim 5, characterized in that, The distance sensor is a length grating.

7. The automatic control system for laser cutting based on a servo motor according to claim 5, characterized in that, The controller mentioned is a PLC controller.

8. A computer-readable storage medium having a controller program stored thereon, characterized in that: When the controller program is executed by the controller, it implements the steps of the automatic control method for laser cutting based on a servo motor as described in any one of claims 1 to 4.

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