Comprehensive compensation method and device for linkage error of five-axis linkage numerical control machine tool

Abstract

The invention relates to the technical field of numerical control machine tool adjustment and control, in particular to a five-axis linkage numerical control machine tool linkage error comprehensive compensation method and device, and the method comprises the steps: designing a feedforward controller, achieving the servo feedforward compensation of a drive shaft of a machining center, perfecting a pre-constructed linkage error prediction model under the servo feedforward compensation, and obtaining a linkage error prediction result; a corrected linkage error prediction model is obtained; determining a feed-forward control coefficient according to a given processing track instruction, and determining a feed-forward compensation residual error after servo feed-forward compensation based on the corrected linkage error prediction model; and on the basis of a pre-constructed instruction correction compensation method model, in combination with the predicted feed-forward compensation residual error, a machining instruction is corrected, so that comprehensive compensation for the linkage error of the multi-axis machining center is realized on the premise that the stability of a control system is not influenced basically. Therefore, the problems that an existing control method of the commercial multi-axis machining center is difficult to consider high linkage machining precision and guarantee the stability of a control system and the like are solved.

Description

Technical Field

[0001] The present application relates to the technical field of adjustment and control of numerically controlled machine tools, and in particular to a method and device for comprehensive compensation of linkage errors of five-axis linkage numerically controlled machine tools. Background Art

[0002] Multi-axis machining centers are important processing equipment in modern manufacturing, which can meet the extensive processing needs of complex parts in various fields. When multi-axis machining centers perform surface processing, linkage errors will inevitably occur during the coordinated movement of multiple drive axes. Especially when performing complex surface processing, the drastic changes in the processing trajectory will make the linkage errors very obvious. Therefore, compensating and controlling the linkage errors of multi-axis machining centers is crucial to improving the processing quality of complex parts.

[0003] Five-axis linkage CNC machine tools can adapt to the processing of various complex parts. Among them, servo tracking error is the main factor affecting the linkage error in the CNC machine tool processing process. Controlling and reducing the tracking error of the single drive axis can indirectly reduce the linkage error of the CNC machine tool to a certain extent.

[0004] At present, in the relevant technologies, the commonly used trajectory planning methods cannot fundamentally achieve perfect smoothing of the complex trajectories of each drive axis; although extensive research on advanced control algorithms can significantly reduce linkage errors, it often leads to reduced control system stability, because its application in commercial multi-axis machining centers is very limited. In contrast, servo feedforward is a method that hardly affects system stability and can improve the tracking performance of the drive axis. However, in scenarios with high machining accuracy requirements, its residual error is large, which will lead to an increase in linkage errors, limiting the machining accuracy of multi-axis machining centers, which needs to be solved urgently. Summary of the invention

[0005] The present application provides a method and device for comprehensive compensation of linkage errors of a five-axis linkage CNC machine tool, so as to solve the problem that the control method of the existing commercial multi-axis machining center is difficult to take into account both high linkage machining accuracy and guarantee the stability of the control system.

[0006] The first aspect of the present application provides a comprehensive compensation method for the linkage error of a five-axis linkage CNC machine tool, comprising the following steps: using a preset feedforward controller to perform servo feedforward compensation on the drive axis of a target five-axis linkage CNC machine tool to determine a target drive axis tracking error calculation expression, and correcting a pre-constructed linkage error prediction model through the target drive axis tracking error calculation expression to obtain a corrected linkage error prediction model, and calculating the linkage error corresponding to the target five-axis linkage CNC machine tool through the corrected linkage error prediction model; determining a feedforward control coefficient corresponding to the feedforward controller according to a preset machining trajectory instruction, and calculating the feedforward compensation residual corresponding to the linkage error based on the feedforward control coefficient and the corrected linkage error prediction model; correcting the machining trajectory instruction based on a pre-constructed instruction correction compensation method model and in combination with the feedforward compensation residual to comprehensively compensate for the linkage error of the target five-axis linkage CNC machine tool.

[0007] Optionally, in one embodiment of the present application, the preset feedforward controller is used to perform servo feedforward compensation on the drive axis of the target five-axis linkage CNC machine tool to determine the target drive axis tracking error calculation expression, and the pre-constructed linkage error prediction model is corrected by the target drive axis tracking error calculation expression to obtain a corrected linkage error prediction model, and the linkage error corresponding to the target five-axis linkage CNC machine tool is calculated by the corrected linkage error prediction model, including: based on the pre-constructed drive axis tracking error prediction model, determining the single drive axis tracking error expression corresponding to the target five-axis linkage CNC machine tool; correcting the target five-axis linkage CNC machine tool by the feedforward controller The drive axis of the axis-linked CNC machine tool performs servo feedforward compensation, and combines the single drive axis tracking error expression to construct a target drive axis tracking error calculation expression, and based on the target drive axis tracking error calculation expression, establish the corrected linkage error prediction model; based on the corrected linkage error prediction model, and in combination with the preset drive axis command position, determine the actual position of the tool tip of the machine tool at any time; obtain the target point closest to the actual position of the tool tip at the current time in the preset machining trajectory command position, and determine the tool tip compensation position according to the position vector corresponding to the target point, so as to calculate the linkage error based on the tool tip compensation position and the actual position of the tool tip.

[0008] Optionally, in one embodiment of the present application, the feedforward control coefficient corresponding to the feedforward controller is determined according to the preset processing trajectory instruction, and the feedforward compensation residual corresponding to the linkage error is calculated based on the feedforward control coefficient and the corrected linkage error prediction model, including: based on the processing trajectory instruction, obtaining the drive axis reference instruction of each axis corresponding to the target five-axis linkage CNC machine tool; determining the feedforward coefficient expression corresponding to the feedforward controller according to the target drive axis tracking error calculation expression, and substituting the drive axis reference instruction of each axis into the feedforward coefficient expression to obtain the feedforward coefficient corresponding to each axis; averaging the feedforward coefficient corresponding to each axis to obtain the feedforward control coefficient during the processing of the target five-axis linkage CNC machine tool; substituting the feedforward control coefficient into the target drive axis tracking error calculation expression to obtain the drive axis tracking error corresponding to the target five-axis linkage CNC machine tool, and calculating the feedforward compensation residual according to the drive axis tracking error and the corrected linkage error prediction model.

[0009] Optionally, in one embodiment of the present application, the processing trajectory instruction is corrected based on the pre-constructed instruction correction and compensation method model and combined with the feedforward compensation residual to comprehensively compensate for the linkage error of the target five-axis linkage CNC machine tool, including: based on the corrected linkage error prediction model and combined with the drive axis instruction position and the drive axis tracking error, calculating the tool tip instruction position and the tool tip actual position; determining the drive axis compensation position according to the tool tip instruction position and the tool tip actual position, and calculating the drive axis position difference between the drive axis actual position and the drive axis compensation position to determine the drive axis compensation instruction according to the drive axis position difference; superimposing the drive axis compensation instruction and the drive axis instruction position to obtain a corrected drive axis instruction position, and based on the corrected drive axis instruction position, comprehensively compensating for the linkage error of the target five-axis linkage CNC machine tool.

[0010] Optionally, in one embodiment of the present application, the target drive axis tracking error calculation expression is:

[0011] in, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; Expressed as i Tracking error of each drive axis; They are position loop proportional gain, speed loop proportional gain and speed loop integral time constant respectively; K t Represents the electromagnetic torque coefficient of the motor; J.bare the reduced moment of inertia of the motor and the lead screw and the viscous friction coefficient of the motor and the lead screw respectively; is the mechanical transmission coefficient; Indicates the drive shaft acceleration; Indicates the acceleration of the drive shaft; Indicates the drive shaft speed; They are the jerk coefficient, acceleration coefficient and velocity coefficient respectively.

[0012] Optionally, in one embodiment of the present application, the mathematical expression of the feedforward coefficient expression is:

[0013] in, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; Expressed as i Tracking error of each drive axis; They are speed loop proportional gain and speed loop integral time constant respectively; K t Represents the electromagnetic torque coefficient of the motor; J.b are the reduced moment of inertia of the motor and the lead screw and the viscous friction coefficient of the motor and the lead screw respectively; is the mechanical transmission coefficient; Indicates the drive shaft acceleration; Indicates the acceleration of the drive shaft; Indicates the drive shaft speed.

[0014] The second aspect of the present application provides a comprehensive compensation device for the linkage error of a five-axis linkage CNC machine tool, including: a model correction module, which is used to use a preset feedforward controller to perform servo feedforward compensation on the drive axis of a target five-axis linkage CNC machine tool to determine the target drive axis tracking error calculation expression, and correct the pre-constructed linkage error prediction model through the target drive axis tracking error calculation expression to obtain a corrected linkage error prediction model, and calculate the linkage error corresponding to the target five-axis linkage CNC machine tool through the corrected linkage error prediction model; a residual calculation module, which is used to determine the feedforward control coefficient corresponding to the feedforward controller according to a preset processing trajectory instruction, and calculate the feedforward compensation residual corresponding to the linkage error based on the feedforward control coefficient and the corrected linkage error prediction model; a comprehensive compensation module, which is used to correct the processing trajectory instruction based on a pre-constructed instruction correction compensation method model, and in combination with the feedforward compensation residual, to comprehensively compensate for the linkage error of the target five-axis linkage CNC machine tool.

[0015] Optionally, in one embodiment of the present application, the model correction module includes: an expression construction unit, which is used to determine the single drive axis tracking error expression corresponding to the target five-axis linkage CNC machine tool based on a pre-constructed drive axis tracking error prediction model; a servo feedforward compensation unit, which is used to perform servo feedforward compensation on the drive axis of the target five-axis linkage CNC machine tool through the feedforward controller, and construct a target drive axis tracking error calculation expression in combination with the single drive axis tracking error expression, and establish the corrected linkage error prediction model based on the target drive axis tracking error calculation expression; a determination unit, which is used to determine the actual position of the tool tip of the machine tool at any time based on the corrected linkage error prediction model and in combination with a preset drive axis instruction position; a first acquisition unit, which is used to obtain the target point in the preset machining trajectory instruction position that is closest to the actual position of the tool tip at the current time, and determine the tool tip compensation position according to the position vector corresponding to the target point, so as to calculate the linkage error based on the tool tip compensation position and the actual position of the tool tip.

[0016] Optionally, in one embodiment of the present application, the residual calculation module includes: a second acquisition unit, used to acquire the drive axis reference instruction of each axis corresponding to the target five-axis linkage CNC machine tool based on the processing trajectory instruction; a first substitution unit, used to determine the feedforward coefficient expression corresponding to the feedforward controller according to the target drive axis tracking error calculation expression, and substitute the drive axis reference instruction of each axis into the feedforward coefficient expression to obtain the feedforward coefficient corresponding to each axis; an averaging unit, used to average the feedforward coefficient corresponding to each axis to obtain the feedforward control coefficient during the processing of the target five-axis linkage CNC machine tool; a second substitution unit, used to substitute the feedforward control coefficient into the target drive axis tracking error calculation expression to obtain the drive axis tracking error corresponding to the target five-axis linkage CNC machine tool, and calculate the feedforward compensation residual based on the drive axis tracking error and the corrected linkage error prediction model.

[0017] Optionally, in one embodiment of the present application, the comprehensive compensation module includes: a first calculation unit, used to calculate the tool tip command position and the tool tip actual position based on the corrected linkage error prediction model and in combination with the drive shaft command position and the drive shaft tracking error; a second calculation unit, used to determine the drive shaft compensation position according to the tool tip command position and the tool tip actual position, and calculate the drive shaft position difference between the drive shaft actual position and the drive shaft compensation position, so as to determine the drive shaft compensation instruction according to the drive shaft position difference; a superposition unit, used to superimpose the drive shaft compensation instruction and the drive shaft instruction position to obtain a corrected drive shaft instruction position, and based on the corrected drive shaft instruction position, comprehensively compensate for the linkage error of the target five-axis linkage CNC machine tool.

[0018] Optionally, in one embodiment of the present application, the target drive axis tracking error calculation expression is:

[0019] in, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; Expressed as i Tracking error of each drive axis; They are position loop proportional gain, speed loop proportional gain and speed loop integral time constant respectively; K t Represents the electromagnetic torque coefficient of the motor; J.b are the reduced moment of inertia of the motor and the lead screw and the viscous friction coefficient of the motor and the lead screw respectively; is the mechanical transmission coefficient; Indicates the drive shaft acceleration; Indicates the acceleration of the drive shaft; Indicates the drive shaft speed; They are the jerk coefficient, acceleration coefficient and velocity coefficient respectively.

[0020] Optionally, in one embodiment of the present application, the mathematical expression of the feedforward coefficient expression is:

[0021] in, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; Expressed as i Tracking error of each drive axis; They are speed loop proportional gain and speed loop integral time constant respectively; K t Represents the electromagnetic torque coefficient of the motor; J.b are the reduced moment of inertia of the motor and the lead screw and the viscous friction coefficient of the motor and the lead screw respectively; is the mechanical transmission coefficient; Indicates the drive shaft acceleration; Indicates the acceleration of the drive shaft; Indicates the drive shaft speed.

[0022] The third aspect of the present application provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the comprehensive compensation method for linkage errors of a five-axis linkage CNC machine tool as described in the above embodiment.

[0023] The fourth aspect of the present application provides a computer-readable storage medium, which stores a computer program. When the program is executed by a processor, it implements the above-mentioned five-axis linkage CNC machine tool linkage error comprehensive compensation method.

[0024] The fifth aspect of the present application provides a computer program product, including a computer program, which is executed to implement the above-mentioned five-axis linkage CNC machine tool linkage error comprehensive compensation method.

[0025] Therefore, the embodiments of the present application have the following beneficial effects: The embodiment of the present application can perform servo feedforward compensation on the drive axis of the target five-axis linkage CNC machine tool by using a preset feedforward controller to determine the target drive axis tracking error calculation expression, and correct the pre-constructed linkage error prediction model through the target drive axis tracking error calculation expression to obtain the corrected linkage error prediction model, and calculate the linkage error corresponding to the target five-axis linkage CNC machine tool through the corrected linkage error prediction model; determine the feedforward control coefficient corresponding to the feedforward controller according to the preset processing trajectory instruction, and calculate the feedforward compensation residual corresponding to the linkage error based on the feedforward control coefficient and the corrected linkage error prediction model; based on the pre-constructed instruction correction compensation method model, and combined with the feedforward compensation residual, correct the processing trajectory instruction to comprehensively compensate for the linkage error of the target five-axis linkage CNC machine tool. The present application can integrate servo feedforward without affecting the stability of the CNC system, control the linkage error residual (i.e., feedforward compensation residual) after servo feedforward compensation, further improve the linkage processing accuracy of the machine tool, and provide an effective linkage error comprehensive compensation strategy for commercial multi-axis machining centers.

[0026] This solves the problem that the existing control methods of commercial multi-axis machining centers are difficult to balance high linkage machining accuracy and ensure the stability of the control system.

[0027] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which: Figure 1 A flowchart of a method for comprehensive compensation of linkage errors of a five-axis linkage CNC machine tool provided according to an embodiment of the present application; Figure 2 A block diagram of a drive shaft servo feedforward compensation control system after adding a speed feedforward controller is provided in one embodiment of the present application; Figure 3A schematic diagram of a sample processing trajectory provided for an embodiment of the present application; Figure 4 A schematic diagram of a command correction compensation method model provided for an embodiment of the present application; Figure 5 A schematic diagram of the execution logic of a five-axis linkage CNC machine tool linkage error comprehensive compensation method provided for one embodiment of the present application; Figure 6 A schematic diagram of a servo feedforward compensation result provided by an embodiment of the present application; Figure 7 A schematic diagram of instruction correction compensation results provided by an embodiment of the present application; Figure 8 This is an example diagram of a five-axis linkage CNC machine tool linkage error comprehensive compensation device according to an embodiment of the present application; Fig. 9 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application.

[0029] Among them, 10-five-axis linkage CNC machine tool linkage error comprehensive compensation device; 100-model correction module, 200-residual calculation module, 300-comprehensive compensation module; 901-memory, 902-processor, 903-communication interface. DETAILED DESCRIPTION

[0030] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0031] The following describes the comprehensive compensation method and device for linkage error of a five-axis linkage CNC machine tool of an embodiment of the present application with reference to the accompanying drawings. In view of the problems mentioned in the above background technology, the present application provides a comprehensive compensation method for linkage error of a five-axis linkage CNC machine tool, in which a preset feedforward controller is used to perform servo feedforward compensation on the drive axis of the target five-axis linkage CNC machine tool to determine the target drive axis tracking error calculation expression, and the pre-constructed linkage error prediction model is corrected by the target drive axis tracking error calculation expression to obtain a corrected linkage error prediction model, and the linkage error corresponding to the target five-axis linkage CNC machine tool is calculated by the corrected linkage error prediction model; the feedforward control coefficient corresponding to the feedforward controller is determined according to the preset processing trajectory instruction, and the feedforward compensation residual corresponding to the linkage error is calculated based on the feedforward control coefficient and the corrected linkage error prediction model; based on the pre-constructed instruction correction compensation method model, and combined with the feedforward compensation residual, the processing trajectory instruction is corrected to comprehensively compensate for the linkage error of the target five-axis linkage CNC machine tool, so that an effective linkage error compensation strategy can be provided for commercial multi-axis machining centers on the premise of ensuring system stability, thereby improving the linkage machining accuracy of the multi-axis machining center. This solves the problem that the existing control methods of commercial multi-axis machining centers are difficult to balance high linkage machining accuracy and ensure the stability of the control system.

[0032] Specifically, Figure 1 A flow chart of a method for comprehensive compensation of linkage errors of a five-axis linkage CNC machine tool provided in an embodiment of the present application.

[0033] like Figure 1 As shown, the five-axis linkage CNC machine tool linkage error comprehensive compensation method includes the following steps: In step S101, a preset feedforward controller is used to perform servo feedforward compensation on the drive axis of the target five-axis linkage CNC machine tool to determine the target drive axis tracking error calculation expression, and the pre-constructed linkage error prediction model is corrected by the target drive axis tracking error calculation expression to obtain a corrected linkage error prediction model, and the linkage error corresponding to the target five-axis linkage CNC machine tool is calculated by the corrected linkage error prediction model.

[0034] The embodiment of the present application can first design a feedforward controller to utilize the feedforward controller to perform servo feedforward compensation on the drive axis of the five-axis linkage CNC machine tool, and under the servo feedforward compensation, improve the pre-constructed drive axis tracking error prediction model to further construct a corrected linkage error prediction model, so as to calculate the linkage error of the five-axis linkage CNC machine tool through the corrected linkage error prediction model.

[0035] Optionally, in one embodiment of the present application, a preset feedforward controller is used to perform servo feedforward compensation on the drive axis of the target five-axis linkage CNC machine tool to determine a target drive axis tracking error calculation expression, and a pre-constructed linkage error prediction model is corrected by the target drive axis tracking error calculation expression to obtain a corrected linkage error prediction model, and the linkage error corresponding to the target five-axis linkage CNC machine tool is calculated by the corrected linkage error prediction model, including: determining a single drive axis tracking error expression corresponding to the target five-axis linkage CNC machine tool based on the pre-constructed drive axis tracking error prediction model; and Servo feedforward compensation is performed on the drive axis of the standard five-axis linkage CNC machine tool, and a target drive axis tracking error calculation expression is constructed in combination with the single drive axis tracking error expression, and a corrected linkage error prediction model is established based on the target drive axis tracking error calculation expression; based on the corrected linkage error prediction model and in combination with the preset drive axis command position, the actual position of the tool tip of the machine tool at any time is determined; the target point closest to the actual position of the tool tip at the current time in the preset machining trajectory command position is obtained, and the tool tip compensation position is determined according to the position vector corresponding to the target point, so as to calculate the linkage error based on the tool tip compensation position and the actual position of the tool tip.

[0036] It should be noted that, according to the pre-built drive shaft tracking error prediction model, the drive shaft tracking error can be expressed as a function of the reference instruction: (1) in, and Respectively i Tracking error and command position of each drive axis; A, B, C is a calculable coefficient; the embodiment of the present application can calculate the value of the coefficient according to the actual use scenario of the machining center, so as to know C Much greater than A and B , so the speed feedforward controller can best achieve tracking control of the drive shaft.

[0037] Optionally, in one embodiment of the present application, the target drive axis tracking error calculation expression is:

[0038] in, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; Expressed as i Tracking error of each drive axis; They are position loop proportional gain, speed loop proportional gain and speed loop integral time constant respectively; K tRepresents the electromagnetic torque coefficient of the motor; J.b are the reduced moment of inertia of the motor and the lead screw and the viscous friction coefficient of the motor and the lead screw respectively; is the mechanical transmission coefficient; Indicates the drive shaft acceleration; Indicates the acceleration of the drive shaft; Indicates the drive shaft speed; They are the jerk coefficient, acceleration coefficient and velocity coefficient respectively.

[0039] Figure 2 This is the block diagram of the drive shaft servo feedforward compensation control system after adding the speed feedforward controller. Figure 2 As shown, is the actual output position, They are the position loop proportional gain, speed loop proportional gain and speed loop integral time constant, J.b are the reduced moment of inertia of the motor and the lead screw and the viscous friction coefficient of the motor and the lead screw, is the mechanical transmission coefficient, is the speed feed-forward coefficient, is the motor output torque, and They are the dynamic torque and the tribological torque respectively.

[0040] Therefore, the embodiment of the present application can derive a calculation expression for the tracking error (i.e., a calculation expression for the target drive axis tracking error) as shown below: (2) in, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; Expressed as i Tracking error of each drive axis; They are position loop proportional gain, speed loop proportional gain and speed loop integral time constant respectively; K t Represents the electromagnetic torque coefficient of the motor; J.b are the reduced moment of inertia of the motor and the lead screw and the viscous friction coefficient of the motor and the lead screw respectively; is the mechanical transmission coefficient; Indicates the drive shaft acceleration; Indicates the acceleration of the drive shaft; Indicates the drive shaft speed; They are the jerk coefficient, acceleration coefficient and speed coefficient for calculating the driving axis tracking error respectively.

[0041] In addition, in the embodiment of the present application, the pre-built linkage error prediction model can be based on the drive axis tracking error to achieve the prediction of the linkage error of the machining center. After adding the servo feedforward compensation, the linkage error is calculated in combination with the new drive axis tracking error expression (i.e., the target drive axis tracking error calculation expression), so as to correct the linkage error prediction model to obtain the corrected linkage error prediction model, and then the actual position of the tool tip at any time in the machining center Can be expressed as instruction location and drive shaft tracking error The function is as follows: (3) in, f It is a display function obtained according to the machining center model.

[0042] Secondly, the tool tip position linkage error Can be expressed as the actual position of the tool tip Tool tip compensation position The distance between them is as follows: (4) Among them, the compensation point refers to the command position of the processing trajectory The point closest to the actual position of the tool tip at this moment (i.e. the nearest target) is the position vector of the tool tip compensation position. .

[0043] Therefore, the embodiment of the present application corrects the linkage error prediction model through the target drive axis tracking error calculation expression to obtain a corrected linkage error prediction model, thereby realizing the calculation of the linkage error of the target five-axis linkage CNC machine tool, and providing a reliable data basis for the subsequent comprehensive compensation of the linkage error.

[0044] In step S102, a feedforward control coefficient corresponding to the feedforward controller is determined according to a preset machining trajectory instruction, and a feedforward compensation residual corresponding to the linkage error is calculated based on the feedforward control coefficient and a modified linkage error prediction model.

[0045] Furthermore, the embodiments of the present application also need to determine a feedforward control coefficient according to a given machining trajectory instruction, and determine the linkage error residual after servo feedforward compensation by utilizing a modified linkage error prediction model.

[0046] Optionally, in one embodiment of the present application, a feedforward control coefficient corresponding to a feedforward controller is determined according to a preset processing trajectory instruction, and a feedforward compensation residual corresponding to the linkage error is calculated based on the feedforward control coefficient and a corrected linkage error prediction model, including: based on the processing trajectory instruction, obtaining the drive axis reference instruction of each axis corresponding to the target five-axis linkage CNC machine tool; determining the feedforward coefficient expression corresponding to the feedforward controller according to the target drive axis tracking error calculation expression, and substituting the drive axis reference instruction of each axis into the feedforward coefficient expression to obtain the feedforward coefficient corresponding to each axis; averaging the feedforward coefficient corresponding to each axis to obtain the feedforward control coefficient during the processing of the target five-axis linkage CNC machine tool; substituting the feedforward control coefficient into the target drive axis tracking error calculation expression to obtain the drive axis tracking error corresponding to the target five-axis linkage CNC machine tool, and calculating the feedforward compensation residual according to the drive axis tracking error and the corrected linkage error prediction model.

[0047] Specifically, Figure 3 This is a schematic diagram of a sample processing trajectory. The present application embodiment can be used Figure 3 The sample machining trajectory shown is used to analyze and verify the linkage error compensation method.

[0048] Optionally, in one embodiment of the present application, the mathematical expression of the feedforward coefficient expression is:

[0049] in, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; Expressed as i Tracking error of each drive axis; They are speed loop proportional gain and speed loop integral time constant respectively; K t Represents the electromagnetic torque coefficient of the motor; J.b are the reduced moment of inertia of the motor and the lead screw and the viscous friction coefficient of the motor and the lead screw respectively; is the mechanical transmission coefficient; Indicates the drive shaft acceleration; Indicates the acceleration of the drive shaft; Indicates the drive shaft speed.

[0050] It should be noted that in order to minimize the tracking error, in the target drive axis tracking error calculation expression, that is, formula (2) needs to be , so that the feedforward coefficient can be determined , as shown below: (5) in, mis the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; Expressed as i Tracking error of each drive axis; They are speed loop proportional gain and speed loop integral time constant respectively; J.b are the reduced moment of inertia of the motor and the lead screw and the viscous friction coefficient of the motor and the lead screw respectively; is the mechanical transmission coefficient; Indicates the drive shaft acceleration; Indicates the acceleration of the drive shaft; Indicates the drive shaft speed.

[0051] From formula (5), we can see that It is a number that fluctuates around 1 and is closely related to the processing instructions.

[0052] Secondly, the embodiment of the present application can obtain the specific drive shaft command position according to the given processing trajectory The reference command of each axis (i.e., the drive axis reference command) is substituted into formula (5) to calculate the reference command of each axis in the entire machining process. Take the average value to determine the processing scenario The value of is the feedforward control coefficient.

[0053] Afterwards, the embodiment of the present application can substitute the feedforward control coefficient into equation (2) to determine the tracking error of the drive axis of the machining center under the sample trajectory: .

[0054] Finally, combined with the linkage error prediction model, the linkage error residual of the machining center after servo feedforward compensation is determined according to formula (3): .

[0055] Therefore, the embodiment of the present application determines the feedforward control coefficient according to the processing trajectory instruction, and combines it with the modified linkage error prediction model to determine the linkage error residual after servo feedforward compensation, thereby effectively ensuring the realization of comprehensive compensation of linkage error.

[0056] In step S103, based on the pre-constructed instruction correction compensation method model and in combination with the feedforward compensation residual, the machining trajectory instruction is corrected to comprehensively compensate for the linkage error of the target five-axis linkage CNC machine tool.

[0057] Furthermore, the embodiments of the present application correct the machining instructions based on a pre-constructed instruction correction and compensation method model combined with the predicted feedforward compensation residual, thereby achieving comprehensive compensation for the linkage error of the multi-axis machining center without substantially affecting the stability of the control system.

[0058] Optionally, in one embodiment of the present application, based on a pre-constructed instruction correction and compensation method model, and in combination with the feedforward compensation residual, the machining trajectory instruction is corrected to comprehensively compensate for the linkage error of the target five-axis linkage CNC machine tool, including: based on the corrected linkage error prediction model, and in combination with the drive axis instruction position and the drive axis tracking error, calculating the tool tip instruction position and the tool tip actual position; determining the drive axis compensation position according to the tool tip instruction position and the tool tip actual position, and calculating the drive axis position difference between the drive axis actual position and the drive axis compensation position, to determine the drive axis compensation instruction according to the drive axis position difference; superimposing the drive axis compensation instruction and the drive axis instruction position to obtain a corrected drive axis instruction position, and based on the corrected drive axis instruction position, comprehensively compensate for the linkage error of the target five-axis linkage CNC machine tool.

[0059] Specifically, Figure 4 This is a schematic diagram of the instruction correction compensation method model. Figure 4 As shown, first, the embodiment of the present application can be based on the pre-built kinematic model of the machining center, through the drive axis command position Calculate the tool tip command position The actual position of the drive shaft ; Secondly, according to the target drive axis tracking error calculation expression given by formula (2), the tracking error of each drive axis is calculated ; Again, combined with the above-mentioned corrected linkage error prediction model, the tool tip position linkage error is calculated Compensation position with drive shaft ; Then, calculate and The difference between , and superimpose it with the drive shaft command position to obtain the corrected drive shaft command position .

[0060] Therefore, the embodiment of the present application realizes the correction of the command position, which together with the servo feedforward compensation constitutes the comprehensive compensation for the linkage error of the multi-axis machining center.

[0061] The following is an explanation of the execution logic of the five-axis linkage CNC machine tool linkage error comprehensive compensation method of the present application in combination with the accompanying drawings.

[0062] Figure 5 This is a schematic diagram of the execution logic of the five-axis linkage CNC machine tool linkage error comprehensive compensation method of this application. Figure 5 As shown, the execution process of the five-axis linkage CNC machine tool linkage error comprehensive compensation method of the present application is as follows: S501: Design a feedforward controller to realize servo feedforward compensation for the drive axis of the machining center, and improve the pre-built linkage error prediction model under the servo feedforward compensation; S502: determining a feedforward control coefficient according to a given machining trajectory instruction, and determining a linkage error residual after servo feedforward compensation based on a linkage error prediction model; S503: Based on the pre-built instruction correction compensation model, combined with the predicted feedforward compensation residual, the machining instruction is corrected, thereby achieving comprehensive compensation for the linkage error of the multi-axis machining center without substantially affecting the stability of the control system.

[0063] The following application takes a multi-axis machining center prototype as an example, and experimentally verifies the comprehensive compensation method for linkage errors of a five-axis linkage CNC machine tool of the present application in combination with the accompanying drawings.

[0064] based on Figure 3 The partial machining trajectory of the aircraft engine integral blade shown in the figure is subjected to machining experiments under three conditions: original three-loop feedback control, servo feedforward compensation, and servo feedforward combined with instruction correction comprehensive compensation. The maximum feed speed of the tool is set to 2500mm / min in the experiment.

[0065] Figure 6 This is a schematic diagram of the servo feedforward compensation results. Figure 7 This is a schematic diagram of the instruction correction compensation result. Figure 6 As shown in Figure 2, according to the measurement results of the actual tool position of the machining center, before and after the servo feedforward compensation, the maximum linkage error of the tool tip position is 1.39 mm and 17.44 μm respectively; the average values ​​are 0.56 mm and 5.98 μm respectively, and the linkage error is reduced from the millimeter level to the micron level; further, as Figure 7 As shown in the figure, the comparison results of the tool tip position linkage error before and after the instruction correction compensation are presented. The results show that the instruction correction compensation further reduces the maximum and average residual values ​​of the servo feedforward compensation by 17.66% and 34.02%, respectively, to 14.36μm and 3.95μm, thereby achieving comprehensive compensation for the linkage error of the machining center and further improving the linkage machining accuracy of the machining center.

[0066] According to the comprehensive compensation method for linkage errors of five-axis linkage CNC machine tools proposed in the embodiment of the present application, servo feedforward compensation is performed on the drive axis of the target five-axis linkage CNC machine tool by using a preset feedforward controller to determine the target drive axis tracking error calculation expression, and the pre-constructed linkage error prediction model is corrected by the target drive axis tracking error calculation expression to obtain a corrected linkage error prediction model, and the linkage error corresponding to the target five-axis linkage CNC machine tool is calculated by the corrected linkage error prediction model; the feedforward control coefficient corresponding to the feedforward controller is determined according to the preset processing trajectory instruction, and the feedforward compensation residual corresponding to the linkage error is calculated based on the feedforward control coefficient and the corrected linkage error prediction model; based on the pre-constructed instruction correction compensation method model, and in combination with the feedforward compensation residual, the processing trajectory instruction is corrected to comprehensively compensate for the linkage error of the target five-axis linkage CNC machine tool, thereby providing an effective linkage error compensation strategy for commercial multi-axis machining centers while ensuring system stability, thereby improving the linkage machining accuracy of the multi-axis machining centers.

[0067] Secondly, the five-axis linkage error comprehensive compensation device for CNC machine tools proposed in the embodiment of the present application is described with reference to the accompanying drawings.

[0068] Figure 8 It is a block diagram of a comprehensive compensation device for linkage errors of a five-axis linkage CNC machine tool according to an embodiment of the present application.

[0069] like Figure 8 As shown, the five-axis linkage CNC machine tool linkage error comprehensive compensation device 10 includes: a model correction module 100, a residual calculation module 200 and a comprehensive compensation module 300.

[0070] Among them, the model correction module 100 is used to use a preset feedforward controller to perform servo feedforward compensation on the drive axis of the target five-axis linkage CNC machine tool to determine the target drive axis tracking error calculation expression, and correct the pre-constructed linkage error prediction model through the target drive axis tracking error calculation expression to obtain a corrected linkage error prediction model, and calculate the linkage error corresponding to the target five-axis linkage CNC machine tool through the corrected linkage error prediction model.

[0071] The residual calculation module 200 is used to determine the feedforward control coefficient corresponding to the feedforward controller according to the preset machining trajectory instruction, and calculate the feedforward compensation residual corresponding to the linkage error based on the feedforward control coefficient and the modified linkage error prediction model.

[0072] The comprehensive compensation module 300 is used to correct the machining trajectory instruction based on the pre-built instruction correction compensation method model and in combination with the feedforward compensation residual to comprehensively compensate for the linkage error of the target five-axis linkage CNC machine tool.

[0073] Optionally, in one embodiment of the present application, the model correction module 100 includes: an expression building unit, a servo feedforward compensation unit, a determination unit and a first acquisition unit.

[0074] Among them, the expression construction unit is used to determine the single drive axis tracking error expression corresponding to the target five-axis linkage CNC machine tool based on the pre-constructed drive axis tracking error prediction model.

[0075] The servo feedforward compensation unit is used to perform servo feedforward compensation on the target five-axis linkage CNC machine tool drive axis through a feedforward controller, and to construct a target drive axis tracking error calculation expression in combination with a single drive axis tracking error expression, and to establish a corrected linkage error prediction model based on the target drive axis tracking error calculation expression.

[0076] The determination unit is used to determine the actual position of the tool tip of the machine tool at any time based on the modified linkage error prediction model and in combination with the preset drive axis command position.

[0077] The first acquisition unit is used to obtain the target point closest to the actual position of the tool tip at the current moment in the preset machining trajectory instruction position, and determine the tool tip compensation position according to the position vector corresponding to the target point, so as to calculate the linkage error based on the tool tip compensation position and the actual position of the tool tip.

[0078] Optionally, in one embodiment of the present application, the residual calculation module includes: a second acquisition unit, a first substitution unit, an averaging unit and a second substitution unit.

[0079] Wherein, the second acquisition unit is used to acquire the driving axis reference instruction of each axis corresponding to the target five-axis linkage CNC machine tool based on the processing trajectory instruction.

[0080] The first substitution unit is used to determine the feedforward coefficient expression corresponding to the feedforward controller according to the target drive shaft tracking error calculation expression, and substitute the drive shaft reference instruction of each axis into the feedforward coefficient expression to obtain the feedforward coefficient corresponding to each axis.

[0081] The averaging unit is used to perform an averaging operation on the feedforward coefficient corresponding to each axis to obtain the feedforward control coefficient in the target five-axis linkage CNC machine tool machining process.

[0082] The second substitution unit is used to substitute the feedforward control coefficient into the target drive axis tracking error calculation expression to obtain the drive axis tracking error corresponding to the target five-axis linkage CNC machine tool, and calculate the feedforward compensation residual according to the drive axis tracking error and the corrected linkage error prediction model.

[0083] Optionally, in one embodiment of the present application, the comprehensive compensation module 300 includes: a first calculation unit, a second calculation unit and a superposition unit.

[0084] Among them, the first calculation unit is used to calculate the tool tip command position and the tool tip actual position based on the modified linkage error prediction model and in combination with the drive shaft command position and the drive shaft tracking error.

[0085] The second calculation unit is used to determine the drive shaft compensation position according to the tool tip command position and the tool tip actual position, and calculate the drive shaft position difference between the drive shaft actual position and the drive shaft compensation position to determine the drive shaft compensation command according to the drive shaft position difference.

[0086] The superposition unit is used to superimpose the drive shaft compensation instruction and the drive shaft instruction position to obtain the corrected drive shaft instruction position, and based on the corrected drive shaft instruction position, comprehensively compensate for the linkage error of the target five-axis linkage CNC machine tool.

[0087] Optionally, in one embodiment of the present application, the target drive axis tracking error calculation expression is:

[0088] in, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; Expressed as i Tracking error of each drive axis; They are position loop proportional gain, speed loop proportional gain and speed loop integral time constant respectively; K t Represents the electromagnetic torque coefficient of the motor; J.b are the reduced moment of inertia of the motor and the lead screw and the viscous friction coefficient of the motor and the lead screw respectively; is the mechanical transmission coefficient; Indicates the drive shaft acceleration; Indicates the acceleration of the drive shaft; Indicates the drive shaft speed; They are the jerk coefficient, acceleration coefficient and velocity coefficient respectively.

[0089] Optionally, in one embodiment of the present application, the mathematical expression of the feedforward coefficient expression is:

[0090] in, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; Expressed as i Tracking error of each drive axis; They are speed loop proportional gain and speed loop integral time constant respectively; Kt Represents the electromagnetic torque coefficient of the motor; J.b are the reduced moment of inertia of the motor and the lead screw and the viscous friction coefficient of the motor and the lead screw respectively; is the mechanical transmission coefficient; Indicates the drive shaft acceleration; Indicates the acceleration of the drive shaft; Indicates the drive shaft speed.

[0091] It should be noted that the above explanation of the embodiment of the method for comprehensive compensation of linkage errors of five-axis linkage CNC machine tools is also applicable to the comprehensive compensation device for linkage errors of five-axis linkage CNC machine tools of this embodiment, and will not be repeated here.

[0092] According to the embodiment of the present application, the five-axis linkage CNC machine tool linkage error comprehensive compensation device includes a model correction module 100, which is used to use a preset feedforward controller to perform servo feedforward compensation on the drive axis of the target five-axis linkage CNC machine tool to determine the target drive axis tracking error calculation expression, and correct the pre-constructed linkage error prediction model through the target drive axis tracking error calculation expression to obtain a corrected linkage error prediction model, and calculate the linkage error corresponding to the target five-axis linkage CNC machine tool through the corrected linkage error prediction model; a residual calculation module 200, which is used to determine the feedforward control coefficient corresponding to the feedforward controller according to the preset processing trajectory instruction, and calculate the feedforward compensation residual corresponding to the linkage error based on the feedforward control coefficient and the corrected linkage error prediction model; a comprehensive compensation module 300, which is used to correct the processing trajectory instruction based on the pre-constructed instruction correction compensation method model, and in combination with the feedforward compensation residual, to comprehensively compensate for the linkage error of the target five-axis linkage CNC machine tool, thereby providing an effective linkage error compensation strategy for commercial multi-axis machining centers while ensuring system stability, thereby improving the linkage machining accuracy of the multi-axis machining centers.

[0093] Fig. 9 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device may include: A memory 901 , a processor 902 , and a computer program stored in the memory 901 and executable on the processor 902 .

[0094] When the processor 902 executes the program, the five-axis linkage CNC machine tool linkage error comprehensive compensation method provided in the above embodiment is implemented.

[0095] Furthermore, the electronic device further comprises: The communication interface 903 is used for communication between the memory 901 and the processor 902 .

[0096] The memory 901 is used to store computer programs that can be executed on the processor 902 .

[0097] The memory 901 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0098] If the memory 901, the processor 902 and the communication interface 903 are implemented independently, the communication interface 903, the memory 901 and the processor 902 can be connected to each other through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Fig. 9 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0099] Optionally, in a specific implementation, if the memory 901, the processor 902 and the communication interface 903 are integrated on a chip, the memory 901, the processor 902 and the communication interface 903 can communicate with each other through an internal interface.

[0100] The processor 902 may be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0101] An embodiment of the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-mentioned comprehensive compensation method for linkage errors of a five-axis linkage CNC machine tool.

[0102] The embodiment of the present application also provides a computer program product, including a computer program, which, when executed, is used to implement the above-mentioned five-axis linkage CNC machine tool linkage error comprehensive compensation method.

[0103] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0104] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0105] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0106] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection with one or N wirings (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways as necessary and then storing it in a computer memory.

[0107] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above embodiment, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0108] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0109] In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0110] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A comprehensive compensation method for linkage error of a five-axis linkage CNC machine tool, characterized in that: The following steps are involved: A preset feedforward controller is used to perform servo feedforward compensation on the drive axis of the target five-axis linkage CNC machine tool to determine a target drive axis tracking error calculation expression, and a pre-constructed linkage error prediction model is corrected by the target drive axis tracking error calculation expression to obtain a corrected linkage error prediction model, and the linkage error corresponding to the target five-axis linkage CNC machine tool is calculated by the corrected linkage error prediction model; Determine a feedforward control coefficient corresponding to the feedforward controller according to a preset machining trajectory instruction, and calculate a feedforward compensation residual corresponding to the linkage error based on the feedforward control coefficient and the corrected linkage error prediction model; Based on a pre-constructed instruction correction and compensation method model and in combination with the feedforward compensation residual, the machining trajectory instruction is corrected to comprehensively compensate for the linkage error of the target five-axis linkage CNC machine tool.

2. The five-axis linkage error comprehensive compensation method for CNC machine tools according to claim 1 is characterized in that: The method uses a preset feedforward controller to perform servo feedforward compensation on the drive axis of the target five-axis linkage CNC machine tool to determine a target drive axis tracking error calculation expression, and corrects a pre-constructed linkage error prediction model by using the target drive axis tracking error calculation expression to obtain a corrected linkage error prediction model, and calculates the linkage error corresponding to the target five-axis linkage CNC machine tool by using the corrected linkage error prediction model, including: Based on a pre-built driving axis tracking error prediction model, determining a single driving axis tracking error expression corresponding to the target five-axis linkage CNC machine tool; Servo feedforward compensation is performed on the target five-axis linkage CNC machine tool drive axis through the feedforward controller, and a target drive axis tracking error calculation expression is constructed in combination with the single drive axis tracking error expression, and based on the target drive axis tracking error calculation expression, the corrected linkage error prediction model is established; Based on the corrected linkage error prediction model and in combination with the preset drive axis command position, the actual position of the tool tip of the machine tool at any time is determined; The target point closest to the actual position of the tool tip at the current moment in the preset machining trajectory instruction position is obtained, and the tool tip compensation position is determined according to the position vector corresponding to the target point, so as to calculate the linkage error based on the tool tip compensation position and the actual position of the tool tip.

3. The five-axis linkage error comprehensive compensation method for CNC machine tools according to claim 2 is characterized in that: Determining a feedforward control coefficient corresponding to the feedforward controller according to a preset machining trajectory instruction, and calculating a feedforward compensation residual corresponding to the linkage error based on the feedforward control coefficient and the corrected linkage error prediction model, includes: Based on the machining trajectory instruction, a driving axis reference instruction of each axis corresponding to the target five-axis linkage CNC machine tool is obtained; Determine a feedforward coefficient expression corresponding to the feedforward controller according to the target drive axis tracking error calculation expression, and substitute the drive axis reference instruction of each axis into the feedforward coefficient expression to obtain a feedforward coefficient corresponding to each axis; An average operation is performed on the feedforward coefficients corresponding to each axis to obtain the feedforward control coefficients in the target five-axis linkage CNC machine tool machining process; The feedforward control coefficient is substituted into the target drive axis tracking error calculation expression to obtain the drive axis tracking error corresponding to the target five-axis linkage CNC machine tool, and the feedforward compensation residual is calculated based on the drive axis tracking error and the corrected linkage error prediction model.

4. The five-axis linkage error comprehensive compensation method for a CNC machine tool according to claim 2 is characterized in that: The pre-built instruction correction compensation method model is combined with the feedforward compensation residual to correct the machining trajectory instruction to comprehensively compensate for the linkage error of the target five-axis linkage CNC machine tool, including: Based on the corrected linkage error prediction model and in combination with the drive shaft command position and the drive shaft tracking error, the tool tip command position and the tool tip actual position are calculated; Determining a drive shaft compensation position according to the tool tip command position and the tool tip actual position, and calculating a drive shaft position difference between the drive shaft actual position and the drive shaft compensation position to determine a drive shaft compensation command according to the drive shaft position difference; The drive shaft compensation instruction and the drive shaft instruction position are superimposed to obtain a corrected drive shaft instruction position, and based on the corrected drive shaft instruction position, the linkage error of the target five-axis linkage CNC machine tool is comprehensively compensated.

5. The five-axis linkage error comprehensive compensation method for CNC machine tools according to claim 2 is characterized in that: The target drive axis tracking error calculation expression is: in, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; Expressed as i Tracking error of each drive axis; They are position loop proportional gain, speed loop proportional gain and speed loop integral time constant respectively; K t Represents the electromagnetic torque coefficient of the motor; J.b are the reduced moment of inertia of the motor and the lead screw and the viscous friction coefficient of the motor and the lead screw respectively; is the mechanical transmission coefficient; Indicates the drive shaft acceleration; Indicates the acceleration of the drive shaft; Indicates the drive shaft speed; They are the jerk coefficient, acceleration coefficient and velocity coefficient respectively.

6. The five-axis linkage error comprehensive compensation method for CNC machine tools according to claim 3 is characterized in that: The mathematical expression of the feedforward coefficient expression is: in, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; Expressed as i Tracking error of each drive axis; They are speed loop proportional gain and speed loop integral time constant respectively; K t Represents the electromagnetic torque coefficient of the motor; J.b are the reduced moment of inertia of the motor and the lead screw and the viscous friction coefficient of the motor and the lead screw respectively; is the mechanical transmission coefficient; Indicates the drive shaft acceleration; Indicates the acceleration of the drive shaft; Indicates the drive shaft speed.

7. A five-axis linkage CNC machine tool linkage error comprehensive compensation device, characterized in that: include: A model correction module is used to perform servo feedforward compensation on the drive axis of the target five-axis linkage CNC machine tool by using a preset feedforward controller to determine a target drive axis tracking error calculation expression, and to correct a pre-constructed linkage error prediction model by using the target drive axis tracking error calculation expression to obtain a corrected linkage error prediction model, and to calculate the linkage error corresponding to the target five-axis linkage CNC machine tool by using the corrected linkage error prediction model; A residual calculation module, used to determine the feedforward control coefficient corresponding to the feedforward controller according to a preset machining trajectory instruction, and calculate the feedforward compensation residual corresponding to the linkage error based on the feedforward control coefficient and the corrected linkage error prediction model; The comprehensive compensation module is used to correct the processing trajectory instruction based on a pre-built instruction correction compensation method model and in combination with the feedforward compensation residual to comprehensively compensate for the linkage error of the target five-axis linkage CNC machine tool.

8. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the comprehensive compensation method for linkage errors of a five-axis linkage CNC machine tool as described in any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement the comprehensive compensation method for linkage errors of a five-axis linkage CNC machine tool as described in any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that The computer program is executed to implement the comprehensive compensation method for linkage errors of a five-axis linkage CNC machine tool as described in any one of claims 1 to 6.

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