Servo unbalance compensation method and system for pipe cutting machine

Abstract

The invention discloses a servo unbalance compensation method and system for a pipe cutting machine, and relates to the technical field of pipe cutting machines. The method comprises the steps that a Z shaft is defined as a follow-up linear shaft, a B shaft is defined as a cutting head rotating shaft, the Z shaft is used for being responsible for vertical lifting to adjust the height of a cutting head, and the B shaft is used for being responsible for controlling the left-right swing angle of the cutting head; sensor calibration is carried out, system accuracy is confirmed through a non-swing follow-up test, and errors are identified through a swing follow-up test; a servo error is analyzed, a compensation value is calculated, the compensation value is applied to a follow-up control algorithm, the actual motion height of the Z axis is adjusted in real time, and even under the condition that the B axis swings, a follow-up height curve approaches a straight line, so that the data accuracy and the cutting precision are improved. By compensating the error between the axis B and the axis Z in real time, it can be ensured that when the cutting head swings, a follow-up height curve approaches to a straight line, and therefore the machining precision of the pipe cutting machine is greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of pipe cutting machines, and in particular to a servo imbalance compensation method and system for a pipe cutting machine. Background Art

[0002] In the current field of pipe cutting machine technology, especially in applications involving high-precision laser cutting processing, the groove following process of the laser head plays a vital role in processing accuracy and efficiency. However, in actual operation, when the laser head follows the groove, multiple joint axes need to coordinate movement at the same time to achieve an accurate cutting path. Due to factors such as motion coupling between various joint axes, mechanical friction, load changes, and imperfect control systems, the servo system is often unbalanced, which in turn affects the processing accuracy and stability of the pipe cutting machine.

[0003] When faced with this imbalance problem, traditional pipe cutting machine servo control systems often find it difficult to provide timely and effective compensation mechanisms, which not only reduces processing accuracy and increases scrap rate, but also affects the operating efficiency and life of the pipe cutting machine. Summary of the invention

[0004] Based on the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a pipe cutting machine servo imbalance compensation method and system to solve the above-mentioned technical problems.

[0005] To achieve the above object, the present invention provides the following technical solution: a pipe cutting machine servo imbalance compensation method, comprising:

[0006] Define the Z axis as the follow-up linear axis and the B axis as the cutting head rotation axis. The Z axis is responsible for vertical lifting to adjust the height of the cutting head, and the B axis is responsible for controlling the left and right swing angle of the cutting head.

[0007] Perform sensor calibration, confirm system accuracy with non-swing follow-up test, and identify errors with swing follow-up test;

[0008] Servo error analysis is performed, compensation values ​​are calculated, and the compensation values ​​are applied to the follow-up control algorithm to adjust the actual movement height of the Z-axis in real time. Even when the B-axis swings, the follow-up height curve approaches a straight line, which is used to improve data accuracy and cutting precision.

[0009] The present invention is further configured to confirm the accuracy of the system through a non-oscillation follow-up test, including:

[0010] When the B-axis does not swing to any preset angle, start the follow-up function to make the Z-axis drop vertically, record the height defined by the follow-up and the actual height detected by the sensor, and check whether the height defined by the follow-up and the actual height detected by the sensor are consistent.

[0011] The present invention is further configured to: the swing follow-up test identification error includes:

[0012] When it is necessary to cut a groove with a specific angle, the B-axis will swing to the preset angle, start the follow-up function, lower the Z-axis, record the height defined by the follow-up and the height actually detected by the sensor, and calculate the height defined by the follow-up and the height actually detected by the sensor.

[0013] The present invention is further configured to apply the compensation value to the follow-up control algorithm to adjust the actual movement height of the Z axis in real time. The calculation logic of the follow-up control algorithm is V_c=gap+∑Z-L2*sinβ*∑B to calculate the real-time adjustment value, wherein V_c is the real-time adjustment value, gap is the follow-up height, L2 is the swing length of the cutting head, L2*sinβ is the position of the current axis, ∑Z is the compensation generated when the Z axis moves up and down, and ∑B is the compensation generated when the B axis swings.

[0014] The present invention also provides a pipe cutting machine servo imbalance compensation system, the system comprising:

[0015] Definition module: define the Z axis as the follow-up linear axis and the B axis as the cutting head rotation axis. The Z axis is responsible for vertical lifting to adjust the height of the cutting head, and the B axis is responsible for controlling the left and right swing angle of the cutting head.

[0016] Calibration module: performs sensor calibration, confirms system accuracy through non-swing follow-up test, and identifies errors through swing follow-up test;

[0017] Compensation module: Analyze servo errors, calculate compensation values, apply compensation values ​​to the follow-up control algorithm, and make real-time adjustments to the actual movement height of the Z-axis. Even when the B-axis swings, the follow-up height curve approaches a straight line, which is used to improve data accuracy and cutting precision.

[0018] The present invention provides a servo imbalance compensation method and system for a pipe cutting machine. The method defines a Z-axis as a follow-up linear axis and a B-axis as a cutting head rotation axis, wherein the Z-axis is responsible for vertical lifting to adjust the height of the cutting head, and the B-axis is responsible for controlling the left and right swing angle of the cutting head; performs sensor calibration, confirms the system accuracy through a non-swinging follow-up test, and identifies errors through a swinging follow-up test; performs servo error analysis, calculates compensation values, applies the compensation values ​​to a follow-up control algorithm, and adjusts the actual movement height of the Z-axis in real time. Even when the B-axis swings, the follow-up height curve approaches a straight line, which is used to improve data accuracy and cutting accuracy. The beneficial effects produced include: the compensation method of the present invention can optimize the servo control system of the pipe cutting machine, reduce the influence of mechanical friction and load changes on cutting accuracy, and make the machine operation more stable and reliable. By compensating the error between the B-axis and the Z-axis in real time, the present invention can ensure that when the cutting head swings, the follow-up height curve approaches a straight line, thereby greatly improving the processing accuracy of the pipe cutting machine.

[0019] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0021] Figure 1 A flow chart of a method for compensating for servo imbalance of a pipe cutting machine is shown as an exemplary embodiment of the present invention;

[0022] Figure 2 A compensation calculation diagram of a servo imbalance compensation method for a pipe cutting machine is shown as an exemplary embodiment of the present invention;

[0023] Figure 3 The present invention is a schematic structural diagram of a servo imbalance compensation system for a pipe cutting machine according to an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0024] The following will describe the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, not for limiting the scope of protection of the present invention.

[0025] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0026] In the following description, numerous details are discussed to provide a more thorough explanation of the embodiments of the present invention. However, it is obvious to those skilled in the art that the embodiments of the present invention can be implemented without these specific details. In other embodiments, well-known structures and devices are shown in the form of block diagrams rather than in detail to avoid making the embodiments of the present invention difficult to understand.

[0027] Embodiment 1

[0028] A method for compensating servo imbalance of a pipe cutting machine, such as Figure 1 As shown, including:

[0029] Define the Z axis as the follow-up linear axis and the B axis as the cutting head rotation axis. The Z axis is responsible for vertical lifting to adjust the height of the cutting head, and the B axis is responsible for controlling the left and right swing angle of the cutting head.

[0030] Perform sensor calibration, confirm system accuracy with non-swing follow-up test, and identify errors with swing follow-up test;

[0031] Servo error analysis is performed, compensation values ​​are calculated, and the compensation values ​​are applied to the follow-up control algorithm to adjust the actual movement height of the Z-axis in real time. Even when the B-axis swings, the follow-up height curve approaches a straight line, which is used to improve data accuracy and cutting precision.

[0032] Specifically, when the angle of the rotating axis is not defined, the B-axis does not swing, and then starts to follow. The machine tool will detect the sensor capacitance value, which is the actual follow-up height value. The Z-axis will drop vertically, and the height defined by the follow-up is consistent with the height detected by the actual sensor.

[0033] When the B-axis swings 45 degrees to the left or right, when the follow-up is turned on, the Z-axis descends, and there will be an error in the height defined by the follow-up, which cannot be consistent with the actual height detected by the sensor.

[0034] Because the servo gap detection is the result of a combination of multiple axes, with different servo errors, the linear axis and the rotary axis also have different effects. When the cutting head swings, there is an error in the height, and the actual swing will be offset, so there is compensation for the B axis and the Z axis. Please refer to Figure 2 The present invention is further configured to apply the compensation value to the follow-up control algorithm to adjust the actual movement height of the Z axis in real time. The calculation logic of the follow-up control algorithm is: V_c=gap+∑Z-L2*sinβ*∑B to calculate the real-time adjustment value, wherein V_c is the real-time adjustment value, gap is the follow-up height, L2 is the swing length of the cutting head, L2*sinβ is the position of the current axis, ∑Z is the compensation generated when the Z axis moves up and down, and ∑B is the compensation generated when the B axis swings. Furthermore, the compensation generated when the Z axis moves up and down is determined by the difference between the actual height detected by the sensor and the preset height, and the compensation generated when the B axis swings is determined by recording the height change of the B axis at different swing angles.

[0035] The present invention is further configured to confirm the accuracy of the system through a non-oscillation follow-up test, including:

[0036] When the B-axis has not swung to any preset angle (including the initial 0-degree position), the follow-up function is started to make the Z-axis drop vertically, record the height defined by the follow-up and the actual height detected by the sensor, and check whether the height defined by the follow-up and the actual height detected by the sensor are consistent, where the initial 0-degree position; specifically, when the B-axis is at the initial 0-degree position or has not swung to any preset angle, the follow-up function is started. This means that the system will keep the B-axis at 0 degrees during initialization or recalibration; after the follow-up function is enabled, the Z-axis starts to drop vertically. During this process, the system will record the height currently defined by the follow-up system (i.e., the expected height) and the height actually detected by the sensor; by comparing the height defined by the follow-up system and the height actually detected by the sensor, the consistency between the two is ensured. This step ensures that the system can accurately detect and adjust the height of the Z-axis when there is no swing (the B-axis is at 0 degrees).

[0037] The present invention is further configured to: the swing follow-up test identification error includes:

[0038] When it is necessary to cut a groove with a specific angle, the B axis will swing to a predetermined angle (including 45 degrees or -45 degrees in the left and right directions), start the follow-up function, make the Z axis drop, record the height defined by the follow-up and the height detected by the actual sensor, and calculate the height defined by the follow-up and the height detected by the actual sensor. Specifically, during the cutting process, when it is necessary to process an interface with a specific angle, the B axis will swing to the corresponding angle according to the preset requirements (for example, swing 45 degrees to the left or -45 degrees to the right). This process is to adapt to different cutting angle requirements; after the B axis reaches the predetermined angle, the system starts the follow-up function. This means that the cutting head will start to move according to the set trajectory and height; after the follow-up function is started, the Z axis starts to drop vertically. In this process, the system will record the height defined by the current follow-up system (that is, the expected height) and the height actually detected by the sensor; by comparing the height defined by the follow-up system and the height actually detected by the sensor, the system can identify the error in height. Calculate the difference between the two heights and make corresponding adjustments to ensure the height accuracy of the cutting head at different swing angles.

[0039] Embodiment 2

[0040] See also Figure 3 , the exemplary pipe cutting machine servo imbalance compensation system comprises:

[0041] Definition module: define the Z axis as the follow-up linear axis and the B axis as the cutting head rotation axis. The Z axis is responsible for vertical lifting to adjust the height of the cutting head, and the B axis is responsible for controlling the left and right swing angle of the cutting head.

[0042] Calibration module: performs sensor calibration, confirms system accuracy through non-swing follow-up test, and identifies errors through swing follow-up test;

[0043] Compensation module: Analyze servo errors, calculate compensation values, apply compensation values ​​to the follow-up control algorithm, and make real-time adjustments to the actual movement height of the Z-axis. Even when the B-axis swings, the follow-up height curve approaches a straight line, which is used to improve data accuracy and cutting precision.

[0044] It should be noted that the servo imbalance compensation system for a pipe cutting machine provided in the above embodiment and the servo imbalance compensation method for a pipe cutting machine provided in the above embodiment belong to the same concept, wherein the specific manner in which each module and unit performs the operation has been described in detail in the method embodiment and will not be repeated here. In practical applications, the servo imbalance compensation system for a pipe cutting machine provided in the above embodiment can allocate the above functions to different functional modules as needed, that is, divide the internal structure of the system into different functional modules to complete all or part of the functions described above, and this is not limited here.

[0045] The above embodiments can be implemented in whole or in part by software, hardware, firmware or any other combination. When implemented by software, the above embodiments can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website site, computer, server or data center to another website site, computer, server or data center by wired (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that contains one or more available media sets. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium. The semiconductor medium can be a solid-state hard disk.

[0046] It should be understood that the term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship, but it may also indicate an "and / or" relationship. Please refer to the context for specific understanding.

[0047] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can be represented by: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0048] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0049] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0050] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0051] In the several embodiments provided in the present application, it should be understood that the disclosed system can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0052] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0053] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0054] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage media include: various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROM), random access memories (RAM), magnetic disks or optical disks.

[0055] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A pipe cutting machine servo imbalance compensation method, applied to a three-dimensional pipe cutting machine, characterized in that: include: Define the Z axis as the follow-up linear axis and the B axis as the cutting head rotation axis. The Z axis is responsible for vertical lifting to adjust the height of the cutting head, and the B axis is responsible for controlling the left and right swing angle of the cutting head. Perform sensor calibration, confirm system accuracy with non-swing follow-up test, and identify errors with swing follow-up test; Servo error analysis is performed, compensation values ​​are calculated, and the compensation values ​​are applied to the follow-up control algorithm to adjust the actual movement height of the Z-axis in real time. Even when the B-axis swings, the follow-up height curve approaches a straight line, which is used to improve data accuracy and cutting precision.

2. A pipe cutting machine servo imbalance compensation method according to claim 1, characterized in that: Confirm system accuracy with wobble-free follow-up testing, including: When the B-axis does not swing to any preset angle, start the follow-up function to make the Z-axis drop vertically, record the height defined by the follow-up and the actual height detected by the sensor, and check whether the height defined by the follow-up and the actual height detected by the sensor are consistent.

3. A pipe cutting machine servo imbalance compensation method according to claim 1, characterized in that: The swing follow-up test identifies errors, including: When a groove with a specific angle needs to be cut, the B-axis will swing to the preset angle, start the follow-up function, lower the Z-axis, record the height defined by the follow-up and the height actually detected by the sensor, and calculate the height defined by the follow-up and the height actually detected by the sensor.

4. A pipe cutting machine servo imbalance compensation method according to claim 3, characterized in that: The compensation value is applied to the follow-up control algorithm to make real-time adjustments to the actual movement height of the Z axis. The calculation logic of the follow-up control algorithm is: V_c=gap+∑Z-L2*sinβ*∑B to calculate the real-time adjustment value, where V_c is the real-time adjustment value, gap is the follow-up height, L2 is the swing length of the cutting head, L2*sinβ is the position of the current axis, ∑Z is the compensation generated when the Z axis moves up and down, and ∑B is the compensation generated when the B axis swings.

5. A pipe cutting machine servo imbalance compensation system, characterized in that: include: Definition module: define the Z axis as the follow-up linear axis and the B axis as the cutting head rotation axis. The Z axis is responsible for vertical lifting to adjust the height of the cutting head, and the B axis is responsible for controlling the left and right swing angle of the cutting head. Calibration module: performs sensor calibration, confirms system accuracy through non-swing follow-up test, and identifies errors through swing follow-up test; Compensation module: Analyze servo errors, calculate compensation values, apply compensation values ​​to the follow-up control algorithm, and make real-time adjustments to the actual movement height of the Z-axis. Even when the B-axis swings, the follow-up height curve approaches a straight line, which is used to improve data accuracy and cutting precision.

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