A method of high speed servo control of a laser cutting head

Abstract

A method for high-speed follow-up control of a laser cutting head, comprising: acquiring the height of a machine tool cutting head and a workpiece in real time through a sensor; calculating a single-cycle follow-up increment by using a segmented high-speed follow-up algorithm according to the height of the machine tool cutting head and the workpiece acquired in real time by the sensor, and controlling the machine tool Z-axis to follow-up positioning; after the machine tool Z-axis follow-up positioning is completed, calculating a single-cycle follow-up increment by using a control algorithm combining constant acceleration and deceleration with a PID algorithm, and controlling the machine tool Z-axis to follow-up cutting; after the follow-up control quantity is calculated, performing smoothing processing on the follow-up control quantity before outputting the follow-up control quantity to a logic axis, and sampling and analyzing follow-up cutting data. The present application directly controls the Z-axis movement to meet the high-speed follow-up cutting demand of the laser cutting head through follow-up positioning control, follow-up cutting control, adaptive parameter adjustment and other designs, which can not only ensure the stability of high-speed follow-up positioning, but also meet the follow-up response of high-speed cutting.

Description

Technical Field

[0001] This invention relates to the field of numerical control, and in particular to a method for high-speed follow-up control of a laser cutting head. Background Technology

[0002] A laser cutting machine is a device that uses a laser emitted from a laser source to focus a high-power-density laser beam into a laser cutting head through an optical path system. The beam is then irradiated onto the surface of the workpiece, causing the workpiece to reach its melting or boiling point. At the same time, high-pressure gas coaxial with the laser beam blows away the molten or vaporized metal, thereby cutting the workpiece.

[0003] In laser cutting, to ensure the workpiece is cut through and to achieve good cutting quality, the height of the laser cutting head needs to be controlled and adjusted in real time to maintain the distance between the cutting head and the workpiece surface. This control method is called servo control. Traditional servo control methods typically involve adding a U-axis and its associated hardware to the Z-axis of the laser cutting machine as an actuator. A separate servo control program in the CNC system controls the movement of the U-axis to adjust the distance between the laser cutting head and the workpiece. This approach makes the laser cutting head structure overly complex, reduces its lifespan, and, due to the limited travel of the U-axis, usually requires Z-axis commands to assist in processing, thus reducing the processing efficiency of laser cutting. Furthermore, the U-axis servo control algorithm typically uses positional PID or incremental PID algorithms to control the U-axis movement. To ensure that the U-axis does not jitter during cutting height positioning, the servo response of the U-axis cannot be adjusted quickly enough to meet the requirements of high-speed laser cutting. Summary of the Invention

[0004] In view of the above problems, the present invention is proposed to provide a method for high-speed follow-up control of a laser cutting head that overcomes or at least partially solves the above problems.

[0005] To address the aforementioned technical problems, the embodiments of this application disclose the following technical solutions:

[0006] A method for high-speed servo control of a laser cutting head includes:

[0007] S100. The height of the machine tool cutting head and the workpiece is obtained in real time through sensors;

[0008] S200. Based on the real-time height of the machine tool cutting head and the workpiece obtained by the sensor, a segmented high-speed follow-up algorithm is used to calculate the single-cycle follow-up increment and control the machine tool Z-axis to perform follow-up positioning.

[0009] S300. After the machine tool Z-axis servo positioning is completed, a control algorithm combining constant acceleration and deceleration and PID algorithm is used to calculate the single-cycle servo increment and control the machine tool Z-axis to perform servo cutting.

[0010] After the S400 follow-up control quantity is calculated, it is smoothed before being output to the logic axis, and the follow-up cutting data is sampled and analyzed.

[0011] Furthermore, in S100, the method by which the sensor acquires the height of the machine tool cutting head and the workpiece in real time includes: measuring the voltage value between the nozzle and the workpiece in real time by a capacitive sensor located at the light outlet of the machine tool cutting head; converting the voltage value into a digital quantity through an IO module; and then inputting it into the CNC system through the CNC system bus; and converting the digital quantity into a measured height d_measure through data conversion.

[0012] Furthermore, in S200, a segmented high-speed servo algorithm is used to calculate the single-cycle servo increment and control the machine tool's Z-axis for servo positioning, specifically including:

[0013] If the measured height d_measure in the current cycle is greater than or equal to the sensor's maximum measured value d_max, then when the measured height d_measure in the current cycle is greater than or equal to the sensor's maximum measured value d_max, the Z-axis is accelerated to the set maximum speed Vmax using a constant acceleration method. That is, the current cycle speed V_c is equal to the previous cycle speed V_last plus the acceleration A.

[0014] .

[0015] Furthermore, in S200, a segmented high-speed servo algorithm is used to calculate the single-cycle servo increment and control the machine tool's Z-axis for servo positioning. Specifically, it also includes:

[0016] When the measured height d_measure in the current cycle is less than the sensor's maximum measured value d_max, the system continues to compare the current speed with the set intermediate transition speed V_m. If the current speed is greater than the set intermediate transition speed V_m, a constant deceleration method is used to control the Z-axis to decelerate to the set intermediate transition speed; that is:

[0017] .

[0018] Furthermore, in S200, a segmented high-speed follow-up algorithm is used to calculate the single-cycle follow-up increment and control the machine tool Z-axis for follow-up positioning. Specifically, it also includes: when the measured height d_measure in the current cycle is less than the maximum measured value d_max of the sensor, the current speed is further judged to be greater than or equal to the set intermediate transition speed V_m. When the current speed is less than or equal to the set intermediate transition speed V_m, the incremental PID method is used to control the Z-axis to adjust the height until the measured height is adjusted to the set positioning height.

[0019] Furthermore, an incremental PID control method is used to adjust the Z-axis height. The PID control method includes:

[0020] The current height error d_cur_err is calculated based on the current measured height d_measure. The height error d_cur_err is equal to the set height d_set minus the current measured height d_measure; that is:

[0021]

[0022] The real-time speed V_p during PID control can be calculated using the current error and the incremental PID algorithm.

[0023] Where d_last_err is the height error of the previous cycle, d_last_err2 is the height error of the cycle before that, P is the PID follower proportional coefficient, I is the PID follower integral coefficient, and P is the PID follower derivative coefficient.

[0024] Furthermore, in the S300, a control algorithm combining constant acceleration / deceleration and PID algorithm is used to calculate the single-cycle follow-up increment, controlling the machine tool's Z-axis to perform follow-up cutting, specifically including:

[0025] An incremental PID algorithm is used to calculate the current cycle increment and obtain the real-time adjustment speed V_p. The speed V_p calculated by the incremental PID algorithm is compared with the set intermediate transition speed V_m. When the speed V_p calculated by the incremental PID algorithm is less than the set intermediate transition speed V_m and the current speed V_c is less than the set intermediate transition speed V_m, that is, when the error between the measured height and the set height is small, the incremental PID algorithm is used to control the Z-axis movement to adjust the height.

[0026] Furthermore, in the S300, a control algorithm combining constant acceleration / deceleration and PID algorithm is used to calculate the single-cycle follow-up increment and control the machine tool's Z-axis to perform follow-up cutting. Specifically, it also includes:

[0027] When the speed V_p calculated by the incremental PID algorithm is greater than the set intermediate transition speed V_m, that is, when the error between the measured height and the set height is large, a constant acceleration method is used to continue the follow-up adjustment, and the adjustment method is as follows:

[0028]

[0029] When the speed calculated by the incremental PID algorithm is less than the set intermediate transition speed V_m and the current speed V_c is greater than the set intermediate transition speed V_m, the constant deceleration method is used to continue the follow-up adjustment, and the adjustment method is as follows:

[0030] .

[0031] Furthermore, in the S300, during the incremental PID control process, the PID integral coefficient is adaptively adjusted in real time according to the actual cutting speed, and the adjustment method is as follows:

[0032] When the speed is less than the set maximum cutting speed, the PID integral coefficient is directly proportional to the speed v, that is:

[0033]

[0034] When the speed is greater than or equal to the set maximum cutting speed, the PID integral coefficient is equal to the set maximum integral coefficient I. max ,Right now:

[0035] .

[0036] Furthermore, in S400, a third-order mean smoothing control method is used to smooth the servo control quantity, which can smooth both the speed and the acceleration.

[0037] The beneficial effects of the above-described technical solutions provided in the embodiments of the present invention include at least the following:

[0038] This invention discloses a method for high-speed servo control of a laser cutting head, comprising: acquiring the height of the machine tool cutting head and the workpiece in real time through a sensor; calculating the single-cycle servo increment using a segmented high-speed servo algorithm based on the height of the machine tool cutting head and the workpiece acquired in real time, and controlling the machine tool Z-axis to perform servo positioning; after the machine tool Z-axis servo positioning is completed, calculating the single-cycle servo increment using a control algorithm combining constant acceleration / deceleration and PID algorithm, and controlling the machine tool Z-axis to perform servo cutting; after the servo control quantity is calculated, smoothing the servo control quantity before outputting it to the logic axis, and sampling and analyzing the servo cutting data.

[0039] This invention directly controls the Z-axis motion through designs such as follow-up positioning control, follow-up cutting control, and adaptive parameter adjustment to meet the high-speed follow-up cutting requirements of the laser cutting head. It can ensure the stability of high-speed follow-up positioning and meet the follow-up response of high-speed cutting.

[0040] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0041] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0042] Figure 1This is a flowchart of a high-speed follow-up control method for a laser cutting head in Embodiment 1 of the present invention;

[0043] Figure 2 This is a logic diagram of a high-speed servo control method for a laser cutting head in Embodiment 1 of the present invention;

[0044] Figure 3 This is a schematic diagram of the high-speed servo positioning design in Embodiment 1 of the present invention;

[0045] Figure 4 This is a flowchart of the PID servo control for constant acceleration and deceleration in Embodiment 1 of the present invention;

[0046] Figure 5(a) is a diagram of the Z-axis position of the follow-up positioning in Embodiment 1 of the present invention;

[0047] Figure 5(b) shows the Z-axis velocity diagram of the follow-up positioning in Embodiment 1 of the present invention;

[0048] Figure 6(a) shows the X-axis velocity of the follow-up cutting in Embodiment 1 of the present invention;

[0049] Figure 6(b) shows the Y-axis speed diagram of the follow-up cutting in Embodiment 1 of the present invention;

[0050] Figure 6(c) is a diagram of the Z-axis speed of the follow-up cutting in Embodiment 1 of the present invention;

[0051] Figure 6(d) is a height measurement diagram of the follow-up cutting in Embodiment 1 of the present invention. Detailed Implementation

[0052] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0053] To address the problems existing in the prior art, embodiments of the present invention provide a method for high-speed follow-up control of a laser cutting head.

[0054] Example 1

[0055] This embodiment discloses a method for high-speed servo control of a laser cutting head, such as... Figure 1 and 2 ,include:

[0056] S100. The height of the machine tool cutting head and the workpiece is obtained in real time by a sensor; In S100 of this embodiment, the method for the sensor to obtain the height of the machine tool cutting head and the workpiece in real time includes: measuring the voltage value between the nozzle and the workpiece in real time by a capacitive sensor located at the light outlet of the machine tool cutting head, converting the voltage value into a digital quantity through an IO module, and then inputting it into the CNC system through the CNC system bus, and the CNC system converting the digital quantity into a measured height d_measure through data conversion.

[0057] In this embodiment, the analog voltage range is 0V ~ 10V, the digital voltage range is 0 ~ 32767, and the measurement height range is 0mm ~ 20mm. The conversion formula for converting the digital voltage N to the measurement height d_measure is as follows:

[0058]

[0059] S200. Based on the real-time height of the machine tool cutting head and the workpiece obtained by the sensor, a segmented high-speed follow-up algorithm is used to calculate the single-cycle follow-up increment and control the machine tool Z-axis to perform follow-up positioning.

[0060] In step S200 of this embodiment, after the CNC system loads the cutting program, it clicks "cycle start" to execute the laser cutting program. After completing the positioning of the X and Y axes, it executes the command to begin positioning and piercing. The positioning speed directly affects the cutting efficiency of the entire cutting program. A segmented high-speed follow-up algorithm is used to calculate the single-cycle follow-up increment and control the machine tool's Z-axis for follow-up positioning. Specifically, this includes:

[0061] If the measured height d_measure in the current cycle is greater than or equal to the sensor's maximum measured value d_max, then when the measured height d_measure in the current cycle is greater than or equal to the sensor's maximum measured value d_max, the Z-axis is accelerated to the set maximum speed Vmax using a constant acceleration method. That is, the current cycle speed V_c is equal to the previous cycle speed V_last plus the acceleration A.

[0062] .

[0063] In some preferred embodiments, a segmented high-speed servo algorithm is used to calculate the single-cycle servo increment and control the machine tool's Z-axis for servo positioning. Specifically, it also includes:

[0064] When the measured height d_measure in the current cycle is less than the sensor's maximum measured value d_max, the system continues to compare the current speed with the set intermediate transition speed V_m. If the current speed is greater than the set intermediate transition speed V_m, a constant deceleration method is used to control the Z-axis to decelerate to the set intermediate transition speed; that is:

[0065] .

[0066] In some preferred embodiments, a segmented high-speed servo algorithm is used to calculate the single-cycle servo increment and control the machine tool Z-axis for servo positioning. Specifically, this further includes: when the measured height d_measure in the current cycle is less than the sensor's maximum measured value d_max, the current speed is further compared to the set intermediate transition speed V_m. When the current speed is less than or equal to the set intermediate transition speed V_m, an incremental PID control method is used to adjust the Z-axis height until the measured height is adjusted to the set positioning height. The incremental PID control method for Z-axis height adjustment includes:

[0067] The current height error d_cur_err is calculated based on the current measured height d_measure. The height error d_cur_err is equal to the set height d_set minus the current measured height d_measure; that is:

[0068]

[0069] The real-time speed V_c during PID control can be calculated using the current error and the incremental PID algorithm.

[0070]

[0071] Where d_last_err is the height error of the previous cycle, d_last_err2 is the height error of the cycle before that, P is the PID follower proportional coefficient, I is the PID follower integral coefficient, and P is the PID follower derivative coefficient.

[0072] This embodiment discloses a segmented high-speed servo positioning control method. For servo control requiring high-speed positioning, such as laser cutting, the PID control process is combined with the acceleration and deceleration process to form a segmented high-speed servo positioning process. The entire positioning process is divided into three segments: the first segment is a constant acceleration control process from zero speed to maximum speed; the second segment is an intermediate transition process from maximum speed to PID control; and the third segment is an incremental PID control positioning process. A schematic diagram is shown below. Figure 3 As shown. This positioning control algorithm can maximize the maximum positioning speed of the follower axis, thereby reducing the positioning process time and improving laser processing efficiency.

[0073] S300. After the machine tool Z-axis servo positioning is completed, a control algorithm combining constant acceleration and deceleration and PID algorithm is used to calculate the single-cycle servo increment and control the machine tool Z-axis to perform servo cutting.

[0074] In S300 of this embodiment, a control algorithm combining constant acceleration / deceleration and PID algorithm is used to calculate the single-cycle follow-up increment and control the machine tool Z-axis to perform follow-up cutting, specifically including:

[0075] An incremental PID algorithm is used to calculate the current cycle increment and obtain the real-time adjustment speed V_p. The speed V_p calculated by the incremental PID algorithm is compared with the set intermediate transition speed V_m. When the speed V_p calculated by the incremental PID algorithm is less than the set intermediate transition speed V_m and the current speed V_c is less than the set intermediate transition speed V_m, that is, when the error between the measured height and the set height is small, the incremental PID algorithm is used to control the Z-axis movement to adjust the height.

[0076] In some preferred embodiments, a control algorithm combining constant acceleration / deceleration and PID algorithm is used to calculate the single-cycle follow-up increment and control the machine tool Z-axis to perform follow-up cutting. Specifically, it also includes:

[0077] When the speed V_p calculated by the incremental PID algorithm is greater than the set intermediate transition speed V_m, that is, when the error between the measured height and the set height is large, a constant acceleration method is used to continue the follow-up adjustment, and the adjustment method is as follows:

[0078]

[0079] When the speed V_p calculated by the incremental PID algorithm is less than the set intermediate transition speed V_m and the current speed V_c is greater than the set intermediate transition speed V_m, the constant deceleration method is used to continue the follow-up adjustment, and the adjustment method is as follows:

[0080] .

[0081] In some preferred embodiments, during incremental PID control, the PID integral coefficient is adaptively adjusted in real time according to the actual cutting speed, as follows:

[0082] When the speed is less than the set maximum cutting speed, the PID integral coefficient is directly proportional to the speed v, that is:

[0083]

[0084] When the speed is greater than or equal to the set maximum cutting speed, the PID integral coefficient is equal to the set maximum integral coefficient I. max ,Right now:

[0085]

[0086] This embodiment uses a combination of a fixed acceleration / deceleration algorithm and a traditional incremental PID algorithm to ensure that the maximum speed and maximum acceleration of the follower shaft are within the set range. During high-speed cutting, when the height error is too large, the sensor error fluctuation will also increase. If the PID control method is still used in this case, the calculated shaft acceleration may exceed the maximum allowable acceleration of the shaft, and the maximum speed may also easily exceed the maximum speed limit. Therefore, incremental PID control is used when the error is small, and fixed acceleration / deceleration control is used when the error is large. The control process is as follows: Figure 4 As shown.

[0087] After the S400 follow-up control quantity is calculated, it is smoothed before being output to the logic axis, and the follow-up cutting data is sampled and analyzed.

[0088] Specifically, in the field of mechanical motion control, motion control cannot generate significant impacts on the machinery. Both servo positioning control and servo cutting control involve constant acceleration / deceleration control stages. During these stages, the sudden increase in acceleration from 0 to A can cause significant impacts on the machinery, affecting not only the stability of the servo but also the lifespan of the mechanical structure. Therefore, after the servo control quantity is calculated, it needs to be smoothed before being output to the axis. This embodiment employs a third-order mean smoothing control method, which can smooth both velocity and acceleration.

[0089] After smoothing the servo control parameters, the X, Y, and Z axis positions and velocities are sampled using the SSTT CNC software, along with height measurement data during the cutting process. The servo positioning data is shown in Figure 5, and the servo cutting data is shown in Figure 6. The data in the figures show that the maximum servo positioning speed of the Z axis reaches 30 m / min during program execution, and the actual servo cutting speed reaches 20 m / min. This achieves both high-speed servo positioning and meets the servo response requirements for high-speed cutting, significantly improving the processing efficiency of laser cutting.

[0090] This embodiment discloses a method for high-speed servo control of a laser cutting head, comprising: acquiring the height of the machine tool cutting head and the workpiece in real time through a sensor; calculating the single-cycle servo increment using a segmented high-speed servo algorithm based on the height of the machine tool cutting head and the workpiece acquired in real time, and controlling the machine tool Z-axis to perform servo positioning; after the machine tool Z-axis servo positioning is completed, calculating the single-cycle servo increment using a control algorithm combining constant acceleration / deceleration and PID algorithm, and controlling the machine tool Z-axis to perform servo cutting; after the servo control quantity is calculated, smoothing the servo control quantity before outputting it to the logic axis, and sampling and analyzing the servo cutting data.

[0091] This embodiment directly controls the Z-axis motion through designs such as follow-up positioning control, follow-up cutting control, and adaptive parameter adjustment to meet the high-speed follow-up cutting requirements of the laser cutting head. It can ensure the stability of follow-up high-speed positioning and meet the follow-up response of high-speed cutting.

[0092] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process may be rearranged without departing from the scope of this disclosure. The appended method claims provide elements of various steps in an exemplary order and are not intended to limit the scope to the specific order or hierarchy described.

[0093] In the detailed description above, various features are combined together in a single embodiment to simplify this disclosure. This approach to disclosure should not be construed as reflecting an intention that embodiments of the claimed subject matter require more features than are explicitly stated in each claim. Rather, as reflected in the appended claims, the invention is presented with fewer features than all of the features in a single disclosed embodiment. Therefore, the appended claims are hereby explicitly incorporated into the detailed description, with each claim representing a separate preferred embodiment of the invention.

[0094] Those skilled in the art will also understand that the various illustrative logic blocks, modules, circuits, and algorithm steps described in conjunction with the embodiments herein can be implemented as electronic hardware, computer software, or a combination thereof. To clearly illustrate the interchangeability between hardware and software, the various illustrative components, blocks, modules, circuits, and steps described above are generally described in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system. Those skilled in the art can implement the described functionality in alternative ways for each specific application; however, such implementation decisions should not be construed as departing from the scope of this disclosure.

[0095] The steps of the methods or algorithms described in conjunction with the embodiments herein can be directly embodied in hardware, software modules executed by a processor, or a combination thereof. The software modules can reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disks, removable disks, CD-ROMs, or any other form of storage medium well known in the art. An exemplary storage medium is connected to the processor, enabling the processor to read information from and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and storage medium can reside in an ASIC. The ASIC can reside in a user terminal. Alternatively, the processor and storage medium can exist as discrete components in the user terminal.

[0096] For software implementation, the techniques described in this application can be implemented using modules (e.g., procedures, functions, etc.) that perform the functions described in this application. This software code can be stored in memory units and executed by a processor. The memory units can be implemented within the processor or outside the processor; in the latter case, they are communicatively coupled to the processor via various means, as is well known in the art.

[0097] The foregoing description includes examples of one or more embodiments. It is certainly impossible to describe all possible combinations of components or methods in order to describe the above embodiments, but those skilled in the art will recognize that further combinations and arrangements of the various embodiments are possible. Therefore, the embodiments described herein are intended to cover all such changes, modifications, and variations that fall within the scope of the appended claims. Furthermore, the term "comprising" as used in the specification or claims is interpreted in a manner similar to the term "including," as interpreted when used as a conjunction in the claims. Additionally, the use of any term "or" in the specification of the claims is intended to mean "non-exclusive or."

Claims

1. A method for high-speed servo control of a laser cutting head, characterized in that, include: S100. The height of the machine tool cutting head and the workpiece is obtained in real time through sensors; S200. Based on the real-time height of the machine tool cutting head and the workpiece obtained by the sensor, a segmented high-speed follow-up algorithm is used to calculate the single-cycle follow-up increment and control the machine tool Z-axis for follow-up positioning. In S200, the segmented high-speed follow-up algorithm is used to calculate the single-cycle follow-up increment and control the machine tool Z-axis for follow-up positioning. Specifically, when the measured height d_measure in the current cycle is less than the maximum measured value d_max of the sensor, the current speed and the set intermediate transition speed V_m are further judged. When the current speed is less than or equal to the set intermediate transition speed V_m, the Z-axis height is adjusted using an incremental PID method until the measured height is adjusted to the set positioning height. In the S200, a segmented high-speed servo algorithm is used to calculate the single-cycle servo increment and control the machine tool's Z-axis for servo positioning. Specifically, this includes: If the measured height d_measure in the current cycle is greater than or equal to the sensor's maximum measured value d_max, then when the measured height d_measure in the current cycle is greater than or equal to the sensor's maximum measured value d_max, the Z-axis is accelerated to the set maximum speed V using a constant acceleration method. - max, that is, the current cycle velocity V_c is equal to the previous cycle velocity V_last plus the acceleration A; that is: ； S300. After the machine tool's Z-axis servo positioning is completed, a control algorithm combining constant acceleration / deceleration and PID algorithm is used to calculate the single-cycle servo increment and control the machine tool's Z-axis to perform servo cutting; S300, the control algorithm combining constant acceleration / deceleration and PID algorithm to calculate the single-cycle servo increment and control the machine tool's Z-axis to perform servo cutting, specifically includes: The incremental PID algorithm is used to calculate the current cycle follow-up increment, obtain the real-time adjustment speed V_p, and judge the magnitude of the speed V_p calculated by the incremental PID algorithm and the set intermediate transition speed V_m. When the speed V_p calculated by the incremental PID algorithm is less than the set intermediate transition speed V_m and the current speed V_c is less than the set intermediate transition speed V_m, that is, when the error between the measured height and the set height is small, the incremental PID algorithm is used to control the Z-axis movement to adjust the height. When the speed V_p calculated by the incremental PID algorithm is greater than the set intermediate transition speed V_m, that is, when the error between the measured height and the set height is large, a constant acceleration method is used to continue the follow-up adjustment, and the adjustment method is as follows: ； When the speed calculated by the incremental PID algorithm is less than the set intermediate transition speed V_m and the current speed V_c is greater than the set intermediate transition speed V_m, the constant deceleration method is used to continue the follow-up adjustment, and the adjustment method is as follows: ； In the S300, during incremental PID control, the PID integral coefficient is adaptively adjusted in real time according to the actual cutting speed. The adjustment method is as follows: When the speed is less than the set maximum cutting speed, the PID integral coefficient is directly proportional to the speed v, that is: ； When the speed is greater than or equal to the set maximum cutting speed, the PID integral coefficient is equal to the set maximum integral coefficient I. max ,Right now: ； After the S400 follow-up control quantity is calculated, it is smoothed before being output to the logic axis, and the follow-up cutting data is sampled and analyzed.

2. The method for high-speed follow-up control of a laser cutting head as described in claim 1, characterized in that, In S100, the method for the sensor to obtain the height of the machine tool cutting head and the workpiece in real time includes: measuring the voltage value between the nozzle and the workpiece in real time by a capacitive sensor located at the light outlet of the machine tool cutting head; the voltage value is converted into a digital quantity by the IO module and then input into the CNC system through the CNC system bus; the CNC system converts the digital quantity into a measured height d_measure through data conversion.

3. The method for high-speed follow-up control of a laser cutting head as described in claim 1, characterized in that, In the S200, a segmented high-speed servo algorithm is used to calculate the single-cycle servo increment and control the machine tool's Z-axis for servo positioning. Specifically, it also includes: When the measured height d_measure in the current cycle is less than the sensor's maximum measured value d_max, the system continues to compare the current speed with the set intermediate transition speed V_m. If the current speed is greater than the set intermediate transition speed V_m, a constant deceleration method is used to control the Z-axis to decelerate to the set intermediate transition speed; that is: 。 4. The method for high-speed follow-up control of a laser cutting head as described in claim 1, characterized in that, The Z-axis height adjustment is controlled using an incremental PID method. The PID adjustment method includes: The current height error d_cur_err is calculated based on the current measured height d_measure. The height error d_cur_err is equal to the set height d_set minus the current measured height d_measure; that is: ； The real-time speed V_p during PID control can be calculated using the current error and the incremental PID algorithm. ； Where d_last_err is the height error of the previous cycle, d_last_err2 is the height error of the cycle before that, P is the PID follower proportional coefficient, I is the PID follower integral coefficient, and P is the PID follower derivative coefficient.

5. The method for high-speed follow-up control of a laser cutting head as described in claim 1, characterized in that, In the S400, a third-order mean smoothing control method is used to smooth the servo control quantity, which can smooth both the speed and the acceleration.

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