Comprehensive Compensation Method and Device for Linkage Error of Five-Axis Simultaneous Control Machine Tools

Abstract

The present application relates to the technical field of numerical control machine tool adjustment and control, and particularly relates to a comprehensive compensation method and device for linkage errors of a five-axis linkage numerical control machine tool. The method includes: designing a feedforward controller to achieve servo feedforward compensation for the drive shafts of the machining center, and under the servo feedforward compensation, improving the pre-constructed linkage error prediction model to obtain a corrected linkage error prediction model; determining the feedforward control coefficient according to the given machining trajectory command, and determining the feedforward compensation residual after servo feedforward compensation based on the corrected linkage error prediction model; based on the pre-constructed instruction correction compensation method model, combining with the predicted feedforward compensation residual, correcting the machining instruction, so as to achieve comprehensive compensation for the linkage errors of a multi-axis machining center on the premise of hardly affecting the stability of the control system. Thus, the problems that the control methods of existing commercial multi-axis machining centers are difficult to balance high linkage machining accuracy and ensure the stability of the control system 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] An embodiment of the first aspect of the present application provides a comprehensive compensation method for the linkage error of a five-axis CNC machine tool, including the following steps: Using a preset feedforward controller to perform servo feedforward compensation on the drive axes of the target five-axis CNC machine tool to determine the calculation expression of the tracking error of the target drive axis, and correcting the pre-constructed linkage error prediction model through the calculation expression of the tracking error of the target drive axis to obtain a corrected linkage error prediction model, and calculating the linkage error corresponding to the target five-axis CNC machine tool through the corrected linkage error prediction model; determining the feedforward control coefficient corresponding to the feedforward controller according to the 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; based on the pre-constructed instruction correction compensation method model, and combining the feedforward compensation residual, correcting the machining trajectory instruction to comprehensively compensate the linkage error of the target five-axis CNC machine tool.

[0007] Optionally, in an embodiment of the present application, the step of using a preset feedforward controller to perform servo feedforward compensation on the drive axes of the target five-axis CNC machine tool to determine the calculation expression of the tracking error of the target drive axis, and correcting the pre-constructed linkage error prediction model through the calculation expression of the tracking error of the target drive axis to obtain a corrected linkage error prediction model, and calculating the linkage error corresponding to the target five-axis CNC machine tool through the corrected linkage error prediction model includes: 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 CNC machine tool; performing servo feedforward compensation on the drive axes of the target five-axis CNC machine tool through the feedforward controller, and combining the single drive axis tracking error expression to construct the calculation expression of the tracking error of the target drive axis, and establishing the corrected linkage error prediction model based on the calculation expression of the tracking error of the target drive axis; based on the corrected linkage error prediction model, and combining the preset drive axis command position, determining the actual position of the tool tip at any time of the machine tool; obtaining the target point closest to the actual position of the tool tip at the current moment in the preset machining trajectory instruction position, and determining 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 an embodiment of the present application, determining the 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 includes: obtaining the drive axis reference instruction of each axis corresponding to the target five-axis linkage numerically controlled machine tool based on the machining trajectory instruction; 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; performing an averaging operation on the feedforward coefficients corresponding to each axis to obtain the feedforward control coefficient during the machining process of the target five-axis linkage numerically controlled 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 numerically controlled 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 an embodiment of the present application, correcting the machining 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 numerically controlled machine tool includes: calculating the tool tip instruction position and the tool tip actual position based on the corrected linkage error prediction model and in combination with the drive axis instruction position and the drive axis tracking error; 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 the corrected drive axis instruction position, and comprehensively compensating for the linkage error of the target five-axis linkage numerically controlled machine tool based on the corrected drive axis instruction position.

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

[0011]

[0012] Where m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; represents the i th drive axis tracking error; are respectively the position loop proportional gain, the speed loop proportional gain, and the speed loop integral time constant; K t represents the motor electromagnetic torque coefficient; J, bare the equivalent 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; represents the jerk of the drive shaft; represents the acceleration of the drive shaft; represents the speed of the drive shaft; are the jerk coefficient, the acceleration coefficient, and the speed coefficient, respectively.

[0013] Optionally, in an embodiment of the present application, the mathematical expression of the feedforward coefficient expression is:

[0014]

[0015] wherein, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; represents the tracking error of the i th drive shaft; are the speed loop proportional gain and the speed loop integral time constant, respectively; K t represents the motor electromagnetic torque coefficient; J, b are the equivalent 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; represents the jerk of the drive shaft; represents the acceleration of the drive shaft; represents the speed of the drive shaft.

[0016] An embodiment of the second aspect of the present application provides a comprehensive compensation device for the linkage error of a five-axis CNC machine tool, including: a model correction module, configured to perform servo feedforward compensation on the drive shafts of the target five-axis CNC machine tool by using a preset feedforward controller to determine an expression for calculating the tracking error of the target drive shaft, and correct a pre-constructed linkage error prediction model through the expression for calculating the tracking error of the target drive shaft to obtain a corrected linkage error prediction model, and calculate the linkage error corresponding to the target five-axis CNC machine tool through the corrected linkage error prediction model; a residual calculation module, configured 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; a comprehensive compensation module, configured to correct 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 the linkage error of the target five-axis CNC machine tool.

[0017] Optionally, in an embodiment of the present application, the model correction module includes: an expression construction unit, configured to determine a single drive axis tracking error expression corresponding to the target five-axis linkage numerical control machine tool based on a pre-constructed drive axis tracking error prediction model; a servo feedforward compensation unit, configured to perform servo feedforward compensation on the drive axes of the target five-axis linkage numerical control machine tool through the feedforward controller, and combine the single drive axis tracking error expression to construct a target drive axis tracking error calculation expression, and establish the corrected linkage error prediction model based on the target drive axis tracking error calculation expression; a determination unit, configured to determine the actual position of the tool tip of the machine tool at any moment based on the corrected linkage error prediction model and in combination with the preset drive axis command position; a first acquisition unit, configured to acquire a target point closest to the actual position of the tool tip at the current moment 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.

[0018] Optionally, in an embodiment of the present application, the residual calculation module includes: a second acquisition unit, configured to acquire the drive axis reference command of each axis corresponding to the target five-axis linkage numerical control machine tool based on the machining trajectory command; a first substitution unit, configured 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 command of each axis into the feedforward coefficient expression to obtain the feedforward coefficient corresponding to each axis; an averaging unit, configured to perform an averaging operation on the feedforward coefficients corresponding to each axis to obtain the feedforward control coefficient during the machining process of the target five-axis linkage numerical control machine tool; a second substitution unit, configured 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 numerical control machine tool, and calculate the feedforward compensation residual according to the drive axis tracking error and the corrected linkage error prediction model.

[0019] Optionally, in an embodiment of the present application, the comprehensive compensation module includes: a first calculation unit, configured to calculate the tool tip command position and the actual position of the tool tip based on the corrected linkage error prediction model and in combination with the drive axis command position and the drive axis tracking error; a second calculation unit, configured to determine the drive axis compensation position according to the tool tip command position and the actual position of the tool tip, and calculate the drive axis position difference between the actual position of the drive axis and the drive axis compensation position, so as to determine the drive axis compensation command according to the drive axis position difference; a superposition unit, configured to superpose the drive axis compensation command and the drive axis command position to obtain a corrected drive axis command position, and comprehensively compensate the linkage error of the target five-axis linkage numerical control machine tool based on the corrected drive axis command position.

[0020] Optionally, in an embodiment of the present application, the calculation expression of the target drive shaft tracking error is:

[0021]

[0022] Wherein, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; represents the tracking error of the i th drive shaft; are respectively the position loop proportional gain, the speed loop proportional gain, and the speed loop integral time constant; K t represents the motor electromagnetic torque coefficient; J, b are respectively the equivalent 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; represents the jerk of the drive shaft; represents the acceleration of the drive shaft; represents the speed of the drive shaft; are respectively the jerk coefficient, the acceleration coefficient, and the speed coefficient.

[0023] Optionally, in an embodiment of the present application, the mathematical expression of the feedforward coefficient expression is:

[0024]

[0025] Wherein, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; represents the i th drive shaft tracking error; are respectively the speed loop proportional gain and the speed loop integral time constant; K t represents the motor electromagnetic torque coefficient; J, b are respectively the equivalent 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; represents the jerk of the drive shaft; represents the acceleration of the drive shaft; represents the speed of the drive shaft.

[0026] In a third aspect of the embodiments of the present application, an electronic device is provided, including: a memory, a processor, and a computer program stored on the memory and executable on the processor, where the processor executes the program to implement the comprehensive compensation method for the linkage error of a five-axis linkage numerically controlled machine tool as described in the above embodiments.

[0027] In a fourth aspect of the embodiments of the present application, a computer-readable storage medium is provided, where the computer-readable storage medium stores a computer program, and when the program is executed by a processor, the comprehensive compensation method for the linkage error of a five-axis linkage numerically controlled machine tool as described above is implemented.

[0028] In a fifth aspect of the embodiments of the present application, a computer program product is provided, including a computer program, where the computer program is executed to implement the comprehensive compensation method for the linkage error of a five-axis linkage numerically controlled machine tool as described above.

[0029] Therefore, the embodiments of the present application have the following beneficial effects:

[0030] The embodiments of the present application can perform servo feedforward compensation on the drive axes of a target five-axis linkage numerically controlled machine tool by using a preset feedforward controller to determine an expression for calculating the tracking error of the target drive axis, and correct a pre-constructed linkage error prediction model through the expression for calculating the tracking error of the target drive axis to obtain a corrected linkage error prediction model, and calculate the linkage error corresponding to the target five-axis linkage numerically controlled machine tool through the corrected linkage error prediction model; 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; and correct 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 the linkage error of the target five-axis linkage numerically controlled machine tool. Without affecting the stability of the numerical control system, the present application can comprehensively perform servo feedforward, control the linkage error residual after servo feedforward compensation (i.e., the feedforward compensation residual), further improve the linkage machining accuracy of the machine tool, and provide an effective comprehensive compensation strategy for the linkage error of a commercial multi-axis machining center.

[0031] Therefore, problems such as the difficulty of the existing control methods for commercial multi-axis machining centers to balance high linkage machining accuracy and ensure the stability of the control system are solved.

[0032] The additional aspects and advantages of the present application will be partially given in the following description, partially become apparent from the following description, or be understood through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description of the embodiments in conjunction with the drawings, where:

[0034] Figure 1 It is a flowchart of a comprehensive compensation method for the linkage error of a five-axis CNC machine tool provided according to an embodiment of the present application;

[0035] Figure 2 It is a block diagram of a drive shaft servo feedforward compensation control system after adding a speed feedforward controller provided by an embodiment of the present application;

[0036] Figure 3 It is a schematic diagram of a sample machining trajectory provided by an embodiment of the present application;

[0037] Figure 4 It is a schematic diagram of an instruction correction compensation method model provided by an embodiment of the present application;

[0038] Figure 5 It is a schematic diagram of the execution logic of a comprehensive compensation method for the linkage error of a five-axis CNC machine tool provided by an embodiment of the present application;

[0039] Figure 6 It is a schematic diagram of the servo feedforward compensation result provided by an embodiment of the present application;

[0040] Figure 7 It is a schematic diagram of the instruction correction compensation result provided by an embodiment of the present application;

[0041] Figure 8 It is an example diagram of a comprehensive compensation device for the linkage error of a five-axis CNC machine tool according to an embodiment of the present application;

[0042] Figure 9 It is a schematic diagram of the structure of an electronic device provided by an embodiment of the present application.

[0043] Among them, 10 - comprehensive compensation device for the linkage error of a five-axis CNC machine tool; 100 - model correction module, 200 - residual calculation module, 300 - comprehensive compensation module; 901 - memory, 902 - processor, 903 - communication interface. Detailed implementation manners

[0044] The embodiments of the present application will be described in detail below. The examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions from beginning to end. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present application, and should not be construed as a limitation of the present application.

[0045] The following describes a comprehensive compensation method and device for the linkage error of a five-axis CNC machine tool according to an embodiment of the present application. In view of the problems mentioned in the above background art, the present application provides a comprehensive compensation method for the linkage error of a five-axis CNC machine tool. In this method, a preset feedforward controller is used to perform servo feedforward compensation on the drive axes of the target five-axis CNC machine tool to determine the calculation expression of the tracking error of the target drive axis, and the pre-constructed linkage error prediction model is corrected through the calculation expression of the tracking error of the target drive axis to obtain a corrected linkage error prediction model, and the linkage error corresponding to the target five-axis CNC machine tool is calculated through the corrected linkage error prediction model; the feedforward control coefficient corresponding to the feedforward controller is determined according to the preset machining trajectory instruction, and based on the feedforward control coefficient and the corrected linkage error prediction model, the feedforward compensation residual corresponding to the linkage error is calculated; 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 the linkage error of the target five-axis CNC machine tool, so as to provide an effective linkage error compensation strategy for commercial multi-axis machining centers on the premise of ensuring system stability, and improve the linkage machining accuracy of multi-axis machining centers. Thus, the problems that the control methods of existing commercial multi-axis machining centers are difficult to take into account both high linkage machining accuracy and ensuring the stability of the control system are solved.

[0046] Specifically, Figure 1 FIG. is a flowchart of a comprehensive compensation method for the linkage error of a five-axis CNC machine tool provided by an embodiment of the present application.

[0047] As Figure 1 shown, the comprehensive compensation method for the linkage error of the five-axis CNC machine tool includes the following steps:

[0048] In step S101, a preset feedforward controller is used to perform servo feedforward compensation on the drive axes of the target five-axis CNC machine tool to determine the calculation expression of the tracking error of the target drive axis, and the pre-constructed linkage error prediction model is corrected through the calculation expression of the tracking error of the target drive axis to obtain a corrected linkage error prediction model, and the linkage error corresponding to the target five-axis CNC machine tool is calculated through the corrected linkage error prediction model.

[0049] In the embodiment of the present application, a feedforward controller can be designed first to perform servo feedforward compensation on the drive axes of the five-axis CNC machine tool by using the feedforward controller, and under the servo feedforward compensation, the pre-constructed tracking error prediction model of the drive axis is improved to further construct a corrected linkage error prediction model, so as to calculate the linkage error of the five-axis CNC machine tool through the corrected linkage error prediction model.

[0050] Optionally, in an embodiment of the present application, a preset feedforward controller is used to perform servo feedforward compensation on the drive axes of the target five-axis linkage numerically controlled machine tool to determine the target drive axis tracking error calculation expression, and the pre-constructed linkage error prediction model is corrected through 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 numerically controlled machine tool is calculated through 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 numerically controlled machine tool; performing servo feedforward compensation on the drive axes of the target five-axis linkage numerically controlled machine tool through the feedforward controller, and combining the single drive axis tracking error expression to construct the target drive axis tracking error calculation expression, and based on the target drive axis tracking error calculation expression, establishing a corrected linkage error prediction model; based on the corrected linkage error prediction model, and combining the preset drive axis command position, determining the actual position of the tool tip at any time of the machine tool; obtaining the target point closest to the actual position of the tool tip at the current moment in the preset machining trajectory command position, and determining 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.

[0051] It should be noted that according to the pre-constructed drive axis tracking error prediction model, the drive axis tracking error can be expressed as a function of the reference command:

[0052] (1)

[0053] Wherein, and are respectively the tracking error and the command position of the i th drive axis; A, B, C is a computable coefficient; in the embodiment of the present application, the numerical value of the coefficient can be calculated according to the actual use scenario of the machining center, so as to know that C is much larger than A and B , so the velocity feedforward controller can best realize the tracking control of the drive axis.

[0054] Optionally, in an embodiment of the present application, the target drive axis tracking error calculation expression is:

[0055]

[0056] Wherein, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; represents the tracking error of the i th drive axis; They are the position loop proportional gain, velocity loop proportional gain, and velocity loop integral time constant respectively; K t represents the motor electromagnetic torque coefficient; J, b They are the equivalent 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; represents the jerk of the drive shaft; represents the acceleration of the drive shaft; represents the velocity of the drive shaft; They are the jerk coefficient, acceleration coefficient, and velocity coefficient respectively.

[0057] Figure 2 is the block diagram of the drive shaft servo feedforward compensation control system after adding the velocity feedforward controller. As Figure 2 shown, is the actual output position, They are the position loop proportional gain, velocity loop proportional gain, and velocity loop integral time constant respectively, J, b They are the equivalent 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, is the velocity feedforward coefficient, is the motor output torque, and are the dynamic torque and tribological torque respectively.

[0058] Thus, the calculation expression of the tracking error (i.e., the target drive shaft tracking error calculation expression) can be derived in the embodiments of this application as shown in the following formula:

[0059] (2)

[0060] Among them, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; is expressed as the i th tracking error of the drive shaft; They are the position loop proportional gain, velocity loop proportional gain, and velocity loop integral time constant respectively; K t represents the motor electromagnetic torque coefficient; J, b They are the equivalent 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; represents the jerk of the drive shaft; represents the acceleration of the drive shaft; represents the velocity of the drive shaft; They are respectively the jerk coefficient, acceleration coefficient, and velocity coefficient for calculating the tracking error of the drive shaft.

[0061] In addition, in the embodiments of the present application, a pre-constructed coupled error prediction model can be based on the drive shaft tracking error to predict the coupled error of the machining center. After adding servo feedforward compensation, combined with the new drive shaft tracking error expression (i.e., the target drive shaft tracking error calculation expression), the coupled error is calculated, thereby correcting the coupled error prediction model to obtain a corrected coupled error prediction model. Furthermore, the actual position of the tool tip at any time of the machining center can be expressed as the commanded position and the drive shaft tracking error as a function, as shown in the following equation:

[0062] (3)

[0063] Where, f is a display function obtained according to the machining center model.

[0064] Secondly, the coupled error of the tool tip position can be expressed as the distance between the actual position of the tool tip and the tool tip compensation position as shown in the following equation:

[0065] (4)

[0066] Where the compensation point refers to the commanded position of the machining trajectory, the point closest to the actual position of the tool tip at this moment (i.e., the nearest target), and the position vector of this point is the tool tip compensation position .

[0067] Thus, the embodiments of the present application correct the coupled error prediction model through the target drive shaft tracking error calculation expression to obtain a corrected coupled error prediction model, thereby realizing the calculation of the coupled error of the target five-axis CNC machine tool and providing a reliable data basis for the subsequent comprehensive compensation of the coupled error.

[0068] In step S102, according to the preset machining trajectory command, the feedforward control coefficient corresponding to the feedforward controller is determined, and based on the feedforward control coefficient and the corrected coupled error prediction model, the feedforward compensation residual corresponding to the coupled error is calculated.

[0069] Furthermore, the embodiments of the present application also need to determine the feedforward control coefficient according to the given machining trajectory command, and determine the coupled error residual after servo feedforward compensation from the corrected coupled error prediction model.

[0070] Optionally, in an embodiment of the present application, a feedforward control coefficient corresponding to a feedforward controller is determined according to a preset machining trajectory instruction, and a feedforward compensation residual corresponding to a linkage error is calculated based on the feedforward control coefficient and a corrected linkage error prediction model, including: obtaining a drive axis reference instruction for each axis of a target five-axis linkage numerical control machine tool based on the machining trajectory instruction; determining a feedforward coefficient expression corresponding to the feedforward controller according to a target drive axis tracking error calculation expression, and substituting the drive axis reference instruction for each axis into the feedforward coefficient expression to obtain a feedforward coefficient corresponding to each axis; performing an averaging operation on the feedforward coefficients corresponding to each axis to obtain a feedforward control coefficient during the machining process of the target five-axis linkage numerical control machine tool; substituting the feedforward control coefficient into the target drive axis tracking error calculation expression to obtain a drive axis tracking error corresponding to the target five-axis linkage numerical control machine tool, and calculating a feedforward compensation residual according to the drive axis tracking error and the corrected linkage error prediction model.

[0071] Specifically, Figure 3 As a schematic diagram of a sample machining trajectory, an embodiment of the present application can utilize Figure 3 the shown sample machining trajectory to analyze and verify the linkage error compensation method.

[0072] Optionally, in an embodiment of the present application, the mathematical expression of the feedforward coefficient expression is:

[0073]

[0074] Wherein, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; is expressed as the tracking error of the i th drive axis; are the speed loop proportional gain and the speed loop integral time constant respectively; K t represents the motor electromagnetic torque coefficient; J, b are the equivalent 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; represents the jerk of the drive axis; represents the acceleration of the drive axis; represents the speed of the drive axis.

[0075] It should be noted that, in order to minimize the tracking error, in the target drive axis tracking error calculation expression, that is, in Equation (2), it is necessary to make , so as to determine the feedforward coefficient , as shown in the following formula:

[0076] (5)

[0077] Among them, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; is expressed as the tracking error of the i th drive shaft; are the velocity loop proportional gain and the velocity loop integral time constant respectively; J, b are the equivalent moments of inertia of the motor and the lead screw and the viscous friction coefficients of the motor and the lead screw respectively; is the mechanical transmission coefficient; represents the jerk of the drive shaft; represents the acceleration of the drive shaft; represents the velocity of the drive shaft.

[0078] As can be seen from Equation (5), is a number that fluctuates around 1 and is closely related to the machining instruction.

[0079] Secondly, according to the given machining trajectory, the specific drive shaft command position value can be obtained in the embodiment of the present application, and the reference commands of each axis (i.e., the drive shaft reference commands) are substituted into Equation (5), and the of each axis in the entire machining process range is averaged, so as to determine value in this machining scenario, that is, the feedforward control coefficient.

[0080] After that, the embodiment of the present application can substitute the feedforward control coefficient into Equation (2), and then the tracking error of the drive shaft of the machining center can be determined under this sample trajectory.

[0081] Finally, combined with the coupled error prediction model, the coupled error residual of the machining center after servo feedforward compensation is determined according to Equation (3).

[0082] Thus, the embodiment of the present application effectively ensures the realization of the comprehensive compensation of the coupled error by determining the feedforward control coefficient according to the machining trajectory command and combining the modified coupled error prediction model to determine the coupled error residual after servo feedforward compensation.

[0083] In step S103, based on the pre-constructed instruction correction compensation method model and combined with the feedforward compensation residual, the machining trajectory instruction is corrected to comprehensively compensate the coupled error of the target five-axis CNC machine tool.

[0084] Furthermore, the embodiments of the present application correct the machining instructions based on a pre-constructed instruction correction compensation method model and in combination with the predicted feedforward compensation residual, so as to achieve comprehensive compensation for the linkage error of a multi-axis machining center on the premise of basically not affecting the stability of the control system.

[0085] Optionally, in an embodiment of the present application, based on a 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 numerical control machine tool, including: calculating the tool tip instruction position and the tool tip actual position based on the corrected linkage error prediction model and in combination with the drive axis instruction position and the drive axis tracking error; 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, so as 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 the corrected drive axis instruction position, and comprehensively compensating for the linkage error of the target five-axis linkage numerical control machine tool based on the corrected drive axis instruction position.

[0086] Specifically, Figure 4 is a schematic diagram of the instruction correction compensation method model. As Figure 4 shown, first, the embodiments of the present application can calculate the tool tip instruction position through the drive axis instruction position according to the pre-constructed kinematic model of the machining center and the drive axis actual position ; secondly, calculate the tracking error of each drive axis according to the target drive axis tracking error calculation expression given in Equation (2) ; thirdly, in combination with the above-mentioned corrected linkage error prediction model, calculate the tool tip position linkage error and the drive axis compensation position ; then, calculate and The difference can obtain the drive axis compensation instruction , and superimpose it with the drive axis instruction position to obtain the corrected drive axis instruction position .

[0087] Thus, the embodiments of the present application realize the correction of the instruction position, and together with the servo feedforward compensation, constitute the comprehensive compensation for the linkage error of the multi-axis machining center.

[0088] The following combines the drawings to illustrate the execution logic of the five-axis linkage numerical control machine tool linkage error comprehensive compensation method of the present application.

[0089] Figure 5 is a schematic diagram of the execution logic of the five-axis linkage numerical control machine tool linkage error comprehensive compensation method of the present application. As Figure 5As shown in the figure, the execution process of the comprehensive compensation method for the linkage error of the five-axis linkage numerically controlled machine tool of the present application is as follows:

[0090] S501: Design a feedforward controller to achieve servo feedforward compensation for the drive shafts of the machining center, and improve the pre-constructed linkage error prediction model under servo feedforward compensation;

[0091] S502: Determine the feedforward control coefficient according to the given machining trajectory instruction, and determine the linkage error residual after servo feedforward compensation based on the linkage error prediction model;

[0092] S503: Based on the pre-constructed instruction correction compensation model, combined with the predicted feedforward compensation residual, correct the machining instruction, so as to achieve the comprehensive compensation of the linkage error of the multi-axis machining center on the premise of basically not affecting the stability of the control system.

[0093] The following takes a multi-axis machining center prototype of the present application as an example, and combines the accompanying drawings to conduct experimental verification on the comprehensive compensation method for the linkage error of the five-axis linkage numerically controlled machine tool of the present application.

[0094] Based on Figure 3 Part of the machining trajectory of the integral blisk of the aero-engine shown, machining experiments are carried out on the sample trajectory under three conditions of original three-loop feedback control, servo feedforward compensation, and servo feedforward combined with instruction correction comprehensive compensation respectively. The maximum feed speed of the tool is set to 2500 mm / min in the experiment.

[0095] Figure 6 It is a schematic diagram of the servo feedforward compensation result, Figure 7 and Figure 6 is a schematic diagram of the instruction correction compensation result. As Figure 7 shown, according to the measurement results of the actual tool position of the machining center, before and after servo feedforward compensation, the maximum values of the linkage error of the tool tip position are 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

[0096] According to the comprehensive compensation method for the coupling error of a five-axis CNC machine tool proposed in the embodiments of the present application, servo feedforward compensation is performed on the drive axes of the target five-axis CNC machine tool by using a preset feedforward controller to determine the calculation expression of the tracking error of the target drive axis, and the pre-constructed coupling error prediction model is corrected through the calculation expression of the tracking error of the target drive axis to obtain a corrected coupling error prediction model, and the coupling error corresponding to the target five-axis CNC machine tool is calculated through the corrected coupling error prediction model; the feedforward control coefficient corresponding to the feedforward controller is determined according to the preset machining trajectory instruction, and based on the feedforward control coefficient and the corrected coupling error prediction model, the feedforward compensation residual corresponding to the coupling error is calculated; 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 the coupling error of the target five-axis CNC machine tool, so that an effective coupling error compensation strategy can be provided for commercial multi-axis machining centers while ensuring the stability of the system, and the coupling machining accuracy of the multi-axis machining center is improved.

[0097] Secondly, a comprehensive compensation device for the coupling error of a five-axis CNC machine tool proposed in the embodiments of the present application will be described with reference to the accompanying drawings.

[0098] Figure 8 It is a block diagram of the comprehensive compensation device for the coupling error of a five-axis CNC machine tool according to the embodiments of the present application.

[0099] As Figure 8 shown, the comprehensive compensation device 10 for the coupling error of the five-axis CNC machine tool includes: a model correction module 100, a residual calculation module 200, and a comprehensive compensation module 300.

[0100] Among them, the model correction module 100 is used to perform servo feedforward compensation on the drive axes of the target five-axis CNC machine tool by using a preset feedforward controller to determine the calculation expression of the tracking error of the target drive axis, and correct the pre-constructed coupling error prediction model through the calculation expression of the tracking error of the target drive axis to obtain a corrected coupling error prediction model, and calculate the coupling error corresponding to the target five-axis CNC machine tool through the corrected coupling error prediction model.

[0101] 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 coupling error based on the feedforward control coefficient and the corrected coupling error prediction model.

[0102] The comprehensive compensation module 300 is used to correct the machining trajectory instruction based on the pre-constructed instruction correction compensation method model and in combination with the feedforward compensation residual to comprehensively compensate the coupling error of the target five-axis CNC machine tool.

[0103] Optionally, in an embodiment of the present application, the model correction module 100 includes: an expression construction unit, a servo feedforward compensation unit, a determination unit, and a first acquisition unit.

[0104] Among them, the expression construction unit is configured to determine a single drive axis tracking error expression corresponding to the target five-axis linkage numerical control machine tool based on a pre-constructed drive axis tracking error prediction model.

[0105] The servo feedforward compensation unit is configured to perform servo feedforward compensation on the drive axis of the target five-axis linkage numerical control machine tool through a feedforward controller, combine the single drive axis tracking error expression to construct a target drive axis tracking error calculation expression, and establish a correction linkage error prediction model based on the target drive axis tracking error calculation expression.

[0106] The determination unit is configured to determine the actual position of the tool tip at any time of the machine tool based on the correction linkage error prediction model and in combination with the preset drive axis command position.

[0107] The first acquisition unit is configured to acquire a target point closest to the actual position of the tool tip at the current moment among the preset machining trajectory command positions, 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.

[0108] Optionally, in an 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.

[0109] Among them, the second acquisition unit is configured to acquire the drive axis reference command of each axis corresponding to the target five-axis linkage numerical control machine tool based on the machining trajectory command.

[0110] The first substitution unit is configured 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 command of each axis into the feedforward coefficient expression to obtain the feedforward coefficient corresponding to each axis.

[0111] The averaging unit is configured to perform an averaging operation on the feedforward coefficients corresponding to each axis to obtain the feedforward control coefficient during the machining process of the target five-axis linkage numerical control machine tool.

[0112] The second substitution unit is configured 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 numerical control machine tool, and calculate the feedforward compensation residual according to the drive axis tracking error and the correction linkage error prediction model.

[0113] Optionally, in an embodiment of the present application, the comprehensive compensation module 300 includes: a first calculation unit, a second calculation unit, and a superposition unit.

[0114] Among them, the first calculation unit is used to calculate the tool tip command position and the tool tip actual position based on the corrected coupling error prediction model and in combination with the drive shaft command position and the drive shaft tracking error.

[0115] 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, so as to determine the drive shaft compensation command according to the drive shaft position difference.

[0116] The superposition unit is used to superpose the drive shaft compensation command and the drive shaft command position to obtain the corrected drive shaft command position, and based on the corrected drive shaft command position, comprehensively compensate the coupling error of the target five-axis linkage numerical control machine tool.

[0117] Optionally, in an embodiment of the present application, the calculation expression of the target drive shaft tracking error is:

[0118]

[0119] Among them, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; represents the tracking error of the i th drive shaft; are the position loop proportional gain, the speed loop proportional gain and the speed loop integral time constant respectively; K t represents the motor electromagnetic torque coefficient; J, b are the equivalent 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; represents the jerk of the drive shaft; represents the acceleration of the drive shaft; represents the speed of the drive shaft; are the jerk coefficient, the acceleration coefficient and the speed coefficient respectively.

[0120] Optionally, in an embodiment of the present application, the mathematical expression of the feedforward coefficient expression is:

[0121]

[0122] Among them, m is the load inertia; is the load viscous friction coefficient; is the feedforward coefficient; represents the i th drive shaft tracking error; They are the speed loop proportional gain and the speed loop integral time constant respectively; K t It represents the motor electromagnetic torque coefficient; J, b They are the equivalent moment of inertia of the motor and the lead screw and the viscous friction coefficient of the motor and the lead screw respectively; It is the mechanical transmission coefficient; It represents the jerk of the drive shaft; It represents the acceleration of the drive shaft; It represents the speed of the drive shaft.

[0123] It should be noted that the foregoing explanation of the embodiment of the comprehensive compensation method for the linkage error of the five-axis CNC machine tool is also applicable to the device for comprehensive compensation of the linkage error of the five-axis CNC machine tool in this embodiment, and will not be elaborated here.

[0124] The device for comprehensive compensation of the linkage error of the five-axis CNC machine tool proposed according to the embodiment of the present application includes a model correction module 100, which is used to perform servo feedforward compensation on the drive shaft of the target five-axis CNC machine tool by using a preset feedforward controller to determine the calculation expression of the target drive shaft tracking error, and correct the pre-constructed linkage error prediction model through the calculation expression of the target drive shaft tracking error to obtain a corrected linkage error prediction model, and calculate the linkage error corresponding to the target five-axis 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 machining trajectory command, 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 machining trajectory command based on the pre-constructed instruction correction compensation method model and in combination with the feedforward compensation residual to comprehensively compensate the linkage error of the target five-axis CNC machine tool, so as to provide an effective linkage error compensation strategy for commercial multi-axis machining centers on the premise of ensuring system stability, and improve the linkage machining accuracy of the multi-axis machining center.

[0125] Figure 9 It is a schematic structural diagram of the electronic device provided by the embodiment of the present application. The electronic device may include:

[0126] A memory 901, a processor 902, and a computer program stored on the memory 901 and executable on the processor 902.

[0127] When the processor 902 executes the program, it implements the comprehensive compensation method for the linkage error of the five-axis CNC machine tool provided in the above embodiment.

[0128] Further, the electronic device further includes:

[0129] A communication interface 903, which is used for communication between the memory 901 and the processor 902.

[0130] A memory 901 for storing a computer program that can be run on a processor 902.

[0131] The memory 901 may include a high-speed RAM memory and may also include a non-volatile memory, such as at least one disk memory.

[0132] 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 interconnected through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the sake of representation, Figure 9 only a thick line is used to represent it in the figure, but it does not mean that there is only one bus or one type of bus.

[0133] Optionally, in a specific implementation, if the memory 901, the processor 902, and the communication interface 903 are integrated on a single chip, the memory 901, the processor 902, and the communication interface 903 can communicate with each other through an internal interface.

[0134] 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.

[0135] The embodiments of the present application also provide a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the comprehensive compensation method for the linkage error of a five-axis linkage numerically controlled machine tool as described above is implemented.

[0136] The embodiments of the present application also provide a computer program product, including a computer program, and when the computer program is executed, it is used to implement the comprehensive compensation method for the linkage error of the five-axis linkage numerically controlled machine tool as described above.

[0137] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of this 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 can be combined in any one or N embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0138] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of this application, the meaning of "N" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0139] Any process or method description shown in the flowchart or described in other ways herein can be understood as representing a module, segment, or part of code including one or N executable instructions for implementing a customized logical function or process, and the scope of the preferred embodiments of this application includes additional implementations, where the functions can be executed in a substantially simultaneous manner or in a reverse order according to the involved functions, rather than in the order shown or discussed, which should be understood by those skilled in the technical field to which the embodiments of this application belong.

[0140] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a definable sequence list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device), or in combination with these instruction execution systems, apparatus, or devices. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in combination with an instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection part (electronic device) having one or N wirings, a portable computer disk cartridge (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically by optically scanning the paper or other media, followed by editing, interpretation, or otherwise processing as appropriate, and then storing it in a computer memory.

[0141] It should be understood that various parts of the present application can be implemented by hardware, software, firmware, or a combination thereof. In the above embodiments, 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 in hardware, as in another embodiment, any one or a combination of the following techniques well known in the art can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc.

[0142] Those of ordinary skill in the art of this technology can understand that all or part of the steps carried by the methods of the above embodiments can be completed by instructing relevant hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiments.

[0143] In addition, each functional unit in various embodiments of the present application may be integrated into one processing module, may exist physically alone for each unit, 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. When 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.

[0144] The above-mentioned storage medium may be a read-only memory, a magnetic disk or an optical disc, 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 should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to 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; The calculating the linkage error corresponding to the target five-axis linkage CNC machine tool by using the modified linkage error prediction model includes: 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; Acquire a target point in a preset machining trajectory command position that is closest to the actual position of the tool tip at the current moment, and determine a tool tip compensation position according to a 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; 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.

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 the pre-built linkage error prediction model by the target drive axis tracking error calculation expression to obtain a 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.

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 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.

5. The method for comprehensive compensation of linkage error of a five-axis linkage CNC machine tool 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.

6. 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; A comprehensive compensation module, used to correct the machining trajectory instruction based on a pre-built instruction correction compensation method model and in combination with the feedforward compensation residual, so as to comprehensively compensate for the linkage error of the target five-axis linkage CNC machine tool; Wherein, the model correction module includes: A determination unit, 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 shaft command position; A first acquisition unit is used to acquire a target point in a preset machining trajectory instruction position that is closest to the actual position of the tool tip at a current moment, and determine a tool tip compensation position according to a 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; The comprehensive compensation module comprises: A first calculation unit, configured to calculate a tool tip command position and a 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, configured to determine a drive shaft compensation position according to the tool tip command position and the tool tip actual position, and calculate a drive shaft position difference between the drive shaft actual position and the drive shaft compensation position, so as to determine a drive shaft compensation command according to the drive shaft position difference; The superposition unit is 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.

7. 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 5.

8. 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 5.

9. 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 5.

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