Gantry double permanent magnet servo motor cross coupling sliding mode synchronization control method based on beam mover part information

Abstract

The invention relates to a gantry double permanent magnet servo motor cross coupling sliding mode synchronous control method based on beam mover part information, and belongs to the technical field of electromechanical control. The method comprises the following steps: calculating a double-motor mover displacement tracking error, a cross coupling error and a cross coupling speed error; calculating a sliding mode surface and a sign function thereof; based on the relative displacement of the cross beam rotor, the dual-motor current is redistributed to compensate the deflection influence of the cross beam; the cross beam rotor q-axis net current, the synchronous displacement error and the speed error serve as input, and the sliding mode gain coefficient is dynamically adjusted through fuzzy reasoning; and finally, outputting the reconstructed q-axis current to realize closed-loop control. According to the method, current redistribution and sliding mode variable gain control are carried out by using part of information of the cross beam rotor, the adverse effects of the non-central position and acceleration motion of the cross beam rotor on the synchronization precision are effectively reduced, the synchronization precision and the response speed of the double-drive gantry platform during dynamic operation are remarkably improved, and the method has important engineering application value.

Description

Technical Field

[0001] This invention belongs to the field of electromechanical control technology, specifically relating to a cross-coupled sliding mode synchronous control method for gantry dual permanent magnet servo motors based on crossbeam mover information, applicable to high-precision gantry drive systems. Background Technology

[0002] Gantry drives are a typical multi-axis servo drive system, available in dual-drive and single-drive configurations. Dual-drive gantry drives with dual permanent magnet servo motors provide stronger thrust by driving the crossbeam with two motors. However, when the parallel motors on both sides of the gantry platform are out of sync, significant crossbeam rotation occurs. Simultaneously, the linear guide rails generate excessive internal forces, leading to additional frictional losses and adversely affecting the mechanical structure and normal system operation. Therefore, synchronous control of dual-drive gantry drives is of significant engineering value for the smooth operation of the gantry system.

[0003] Gantry platform motion synchronization control can be divided into two categories: model-free and model-based. Model-free control methods, when dealing with nonlinear, strongly coupled gantry systems, often require complex controller design or pre-fitting of the system, and suffer from poor synchronization accuracy, especially exhibiting significant synchronization errors during dynamic processes. However, they do not require precise modeling of the gantry system or accurate parameters for each component. Model-based control methods offer better dynamic synchronization performance, but require detailed modeling of complex gantry systems. Some parameters can only be obtained through identification, making model-based gantry control directly affected by the accuracy of parameter identification.

[0004] Traditional cross-coupled sliding mode synchronization control is a typical model-free control strategy that couples tracking error and synchronization error to achieve two-axis synchronization. Current cross-coupled sliding mode synchronization control has two defects: (1) it does not use the gantry beam information, resulting in a large dynamic synchronization error between the two motors when the beam mover is in a non-center position of the beam; (2) it does not use the acceleration information of the beam mover along the beam to automatically adjust the sliding mode control parameters, resulting in the acceleration motion of the beam mover along the beam direction having a serious adverse effect on the synchronous operation of the two motors.

[0005] Therefore, in order to effectively improve the synchronization accuracy of the dual-drive gantry platform during dynamic operation, a gantry dual permanent magnet servo motor cross-coupling sliding mode synchronization control method based on the information of the crossbeam mover is proposed. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a gantry dual permanent magnet servo motor cross-coupled sliding mode synchronous control method with high synchronization accuracy and fast dynamic response. This invention effectively improves the synchronization accuracy of the dual-drive gantry platform during dynamic operation by utilizing the information of the crossbeam mover part for current redistribution and sliding mode variable gain control.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: a gantry dual permanent magnet servo motor cross-coupling sliding mode synchronous control method based on crossbeam mover information, comprising the following steps:

[0008] (1) Obtain the displacement of the dual-motor mover of the driving beam and the given value of beam displacement Calculate the displacement tracking error e of the dual-motor mover. i , where i=1,2 refer to two permanent magnet servo motors respectively;

[0009] (2) Calculate the cross-coupling error e of the two motors hi and cross-coupling speed error ;

[0010] (3) Calculate the sliding surface S i ;

[0011] (4) Based on the sliding surface S i Calculate the sign function sgn(S) of the sliding surface. i );

[0012] (5) Based on the sliding surface S i Sliding surface sign function sgn(S i Given acceleration Cross-coupling speed error And the sliding mode variable gain coefficient α, calculate the sliding mode synchronization intermediate current I. i :

[0013] (6) Based on the intermediate current I of sliding mode synchronization i Calculate the cross-coupling sliding mode current i smci ;

[0014] (7) Based on the mass m of the dual-motor mover i , crossbeam mass m h Mass m of the moving part on the crossbeam d , Length L of the crossbeam, Displacement y of the crossbeam mover d and cross-coupled sliding mode current i smci Calculate the cross-coupled sliding mode reconfiguration current i smci0 ;

[0015] (8) In the cross-coupled sliding mode reconstruction current i smci0 Above, superimposed frictional equivalent current ifi Obtain the q-axis current of the dual motors ;

[0016] (9) Using vector control to realize the q-axis current of dual motors Closed-loop control.

[0017] Furthermore, in step (5), the sliding mode variable gain coefficient α is obtained through fuzzy inference, and its implementation method is as follows:

[0018] (5.1) The absolute value of the net current e along the q-axis of the beam mover a The absolute value of the synchronous displacement error e of the dual-motor mover p and the absolute value of the synchronization speed error e v As the fuzzy input variable of the variable gain fuzzy controller; where, Design 5 fuzzy sets: zero (Z), small (S), medium (M), large (B), and very large (VB). and Design three fuzzy sets for each: small (S), medium (M), and large (B); and design the corresponding triangular membership functions. , , , , , , , , , , as follows:

[0019] (10)

[0020] (11)

[0021] (12)

[0022] (13)

[0023] (14)

[0024] (15)

[0025] (16)

[0026] (17)

[0027] (18)

[0028] (19)

[0029] (20)

[0030] (5.2) Perform fuzzy inference based on the fuzzy rule table, and set 8 fuzzy sets for α: zero (Z), very small (VS), small (S), medium-small (MS), medium (M), medium-large (MB), large (B), and very large (VB), with the corresponding output being η. αZ η αVS η αS η αMS η αM η αMB η αB η αVB ;

[0031] The fuzzy rule table includes the following fuzzy rules:

[0032] (twenty one)

[0033] In the fuzzy rule table, the same rule takes the smaller value from the three rule premises, and different rules of the same fuzzy set take the larger value, in order to calculate the membership degree corresponding to α.

[0034] (5.3) The output is obtained by defuzzifying using the centroid method. , where j = Z, VS, S, MS, M,MB, B, VB.

[0035] Compared with existing technologies, this invention has the following advantages: Based on the principle of the influence of the crossbeam mover's displacement relative to the crossbeam on the crossbeam deflection, this invention redistributes the current of the dual permanent magnet servo motors, reducing the adverse effects of the crossbeam mover's off-center position on the dynamic synchronous displacement error of the dual motors. Furthermore, this invention constructs a sliding mode variable gain control strategy based on the crossbeam mover's q-axis net current, the synchronous displacement error of the dual permanent magnet servo motor mover, and the synchronous speed error, further reducing the adverse effects of the crossbeam mover's dynamic motion along the crossbeam on the dynamic synchronous displacement error of the dual motors. Through its innovative control strategy, this invention effectively solves the key technical challenges in the synchronous control of a dual-drive gantry system, and has significant engineering application value. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the gantry platform structure in an embodiment of the present invention;

[0037] Figure 2 This is a block diagram illustrating the implementation principle of the gantry dual permanent magnet servo motor cross-coupling sliding mode synchronous control method based on crossbeam mover information in this embodiment of the invention.

[0038] Figure 3This is a block diagram illustrating the fuzzy inference principle of sliding mode variable gain coefficient in this embodiment of the invention.

[0039] Figure 4 This is a fuzzy input membership function graph in an embodiment of the present invention;

[0040] Figure 5 This is a schematic diagram of the hardware structure of the driving system implemented in an embodiment of the present invention. Detailed Implementation

[0041] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0042] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0043] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0044] This invention provides a gantry dual permanent magnet servo motor cross-coupling sliding mode synchronization control method based on crossbeam mover information. To overcome the significant error inherent in cross-coupling sliding mode synchronization control, the current of the dual permanent magnet servo motors is redistributed based on the principle of the influence of the crossbeam mover's displacement relative to the crossbeam on the crossbeam deflection, thereby reducing dynamic synchronization displacement error. A sliding mode variable gain control strategy is constructed based on the crossbeam mover's q-axis net current, the dual permanent magnet servo motor mover synchronization displacement error, and the synchronization speed error, to further reduce the impact of the crossbeam mover's dynamic movement along the crossbeam on the dynamic synchronization displacement error. This invention can effectively improve the synchronization accuracy of a dual-drive gantry platform during dynamic operation, further enhancing the dynamic response speed of the gantry system.

[0045] In this embodiment, a typical gantry platform structure is as follows: Figure 1 As shown. Rotary bearings are connected to both ends of the crossbeam. The rotary bearing at the right end is connected to the right-side Y-axis slide rail to provide the Y-axis displacement required for the crossbeam's deflection. d is the distance from the center of mass of the crossbeam's mover to the line connecting the centers of the rotary bearings at both ends of the crossbeam; F d f d μ d m d y d These are the electromagnetic thrust, Coulomb friction, viscous friction coefficient, mass, and displacement along the beam from the left end of the beam, respectively; L, mh These are the length and mass of the beam, respectively; F i f i μ i m i x i (i=1,2) represent the electromagnetic thrust, Coulomb friction, viscous friction coefficient, mass, and displacement along the X direction of the dual-motor actuator, respectively; θ is the torsional angle of the beam; R, f R μ R f3, μ3, and x3 represent the radius, Coulomb friction force, and viscous friction coefficient of the bearings at both ends of the crossbeam, respectively; f3, μ3, and x3 represent the Coulomb friction force, viscous friction coefficient, and displacement of the right end of the crossbeam on the Y-axis slide rail, respectively.

[0046] The implementation principle of the gantry dual permanent magnet servo motor cross-coupling sliding mode synchronous control method based on the information of the crossbeam mover provided in this embodiment is as follows: Figure 2 As shown. Based on the given displacement x m and the actual displacement x of the dual motors i (i=1,2) Calculate the displacement tracking error e of the dual permanent magnet motor mover. i (i=1,2); Calculate the cross-coupling error e of the dual permanent magnet servo motors based on the displacement tracking error of the dual motors and the cross-coupling coefficient β. hi (i=1,2); Calculate the sliding surface S based on the cross-coupling error. i (i=1,2); Calculate the sign function sgn(S) based on the sliding surface. i (i=1,2); based on the sliding surface S i (i=1,2), sliding surface sign function sgn(S i (i=1,2) Given acceleration Cross-coupling speed error Given (i=1,2) and the sliding mode variable gain coefficient α, calculate the intermediate current I of sliding mode synchronization. i (i=1,2); Calculate the cross-coupled sliding mode current i based on the intermediate current of sliding mode synchronization. smci (i=1,2); based on the mass m of each part of the gantry i , Length L of the crossbeam, Displacement y of the crossbeam mover d And the cross-coupled sliding mode current, calculate the cross-coupled sliding mode reconstruction current i. smci0 (i=1,2); The frictional equivalent current i is superimposed on the cross-coupled sliding mode reconstruction current. fi (i=1,2), obtain the q-axis current of the dual motors; use vector control and other methods to achieve closed-loop control of the q-axis current of the dual motors. The absolute value of the net q-axis current of the beam mover is used as the starting point. Absolute value of synchronous displacement error of dual motor movers and absolute value of synchronization speed error The input to the variable gain fuzzy controller is fed into the fuzzy inference module with sliding mode variable gain coefficients. Its implementation principle is as follows: Figure 3 As shown, the output sliding mode variable gain coefficient α.

[0047] The specific implementation steps of the gantry dual permanent magnet servo motor cross-coupling sliding mode synchronous control method based on the information of the crossbeam mover part provided in this embodiment are as follows.

[0048] (1) Read the displacement of the dual-motor mover of the drive beam and the given value of beam displacement Calculate the displacement tracking error e of the dual-motor mover. i Where i=1,2 represent two permanent magnet servo motors respectively:

[0049] (1).

[0050] (2) Calculate the cross-coupling error e of the two motors hi and cross-coupling speed error :

[0051] (2)

[0052] Where β is the cross-coupling coefficient; For e hi The differential.

[0053] (3) Calculate the sliding surface S i :

[0054] (3)

[0055] Among them, c i1 c i2 These are the cross-coupling error coefficient and its differential coefficient, respectively.

[0056] (4) Based on the sliding surface S i Calculate the sign function sgn(S) of the sliding surface. i ):

[0057] (4).

[0058] (5) Based on the sliding surface S i Sliding surface sign function sgn(S i Given acceleration Cross-coupling speed error And the sliding mode variable gain coefficient α, calculate the sliding mode synchronization intermediate current I. i :

[0059] (5)

[0060] in, , , , These are the set controller constants, all of which are positive values. In this embodiment, k11=k21=1.2, k12=k22=100.

[0061] (6) Based on the intermediate current I of sliding mode synchronization i Calculate the cross-coupling sliding mode current i smci :

[0062] (6)

[0063] Where m1 and m2 are the masses of the two permanent magnet servo motors, respectively, and K is the mass of the two permanent magnet servo motors. f1 K f2 The thrust coefficient of the two permanent magnet servo motors is given.

[0064] (7) Based on the mass m of the dual-motor mover i , crossbeam mass m h Mass m of the moving part on the crossbeam d , Length L of the crossbeam, Displacement y of the crossbeam mover d and cross-coupled sliding mode current i smci Calculate the cross-coupled sliding mode reconfiguration current i smci0 :

[0065] (7)

[0066] For equation (7), we have:

[0067] (8)

[0068] in, , m d Let y be the mass of the moving part on the beam. d L represents the displacement along the beam from its left end, where L is the beam length in meters. h The mass of the crossbeam.

[0069] (8) In the cross-coupled sliding mode reconstruction current i smci0 Above, superimposed frictional equivalent current i fi Obtain the q-axis current of the dual motors :

[0070] (9).

[0071] (9) Using vector control to realize the q-axis current of dual motors Closed-loop control.

[0072] In step (5), the sliding mode variable gain coefficient α is obtained through fuzzy inference, and its implementation method is as follows:

[0073] (5.1) The absolute value of the net current along the q-axis of the beam mover (where i) qd F is the q-axis current of the beam motor. Ld K represents the equivalent load force of the beam. fd (This refers to the crossbeam thrust coefficient) and the absolute value of the synchronous displacement error of the dual-motor mover. and absolute value of synchronization speed error As the fuzzy input variable of the variable gain fuzzy controller; where, Design 5 fuzzy sets: zero (Z), small (S), medium (M), large (B), and very large (VB). and Design three fuzzy sets for each: small (S), medium (M), and large (B); and design the corresponding triangular membership functions. , , , , , , , , , , like Figure 4 As shown below:

[0074] (10)

[0075] (11)

[0076] (12)

[0077] (13)

[0078] (14)

[0079] (15)

[0080] (16)

[0081] (17)

[0082] (18)

[0083] (19)

[0084] (20)

[0085] (5.2) Perform fuzzy inference based on the fuzzy rule table, and set 8 fuzzy sets for α: zero (Z), very small (VS), small (S), medium-small (MS), medium (M), medium-large (MB), large (B), and very large (VB), with the corresponding output being η. αZ η αVS η αS η αMS η αM η αMB η αB η αVB η αZ η αVS η αS η αMS η αM η αMB η αB η αVB For the predefined positive constants, representing each μ α The corresponding output. In this embodiment, the values ​​are 0, 1, 2, 3, 4, 5, 6, and 7.

[0086] The fuzzy rule table is used to extract from... , , , , , , , , , , Calculate the corresponding μ α To match the configured η α By combining these factors, the final sliding mode variable gain coefficient α can be calculated.

[0087] The fuzzy rule table is shown in Tables 1-5, and specifically includes the following fuzzy rules:

[0088] (twenty one)

[0089]

[0090]

[0091]

[0092]

[0093]

[0094] In the fuzzy rule table, the same rule uses the smallest value among its three premises, while different rules within the same fuzzy set use the largest value, to calculate the membership degree corresponding to α. (Using μ...) αVS Taking the calculation as an example, the larger operation is used between different rules of the same fuzzy set, which means that there are two μ values ​​in the table. αVS Take the larger of the two as the final μ. αVS The same rule applies the minimum value operation to the three rule premises, which specifies two μ values. αVS How are the first μ obtained respectively? αVS Take μ aZ μ vM μ pS The smallest of the three, the second μ αVS Take μ aZ μ vS μ pM The smallest of the three.

[0095] (5.3) The output is obtained by defuzzifying using the centroid method. , where j = Z, VS, S, MS, M,MB, B, VB.

[0096] The hardware structure of the driver system implemented in this embodiment is as follows: Figure 5 As shown. The gantry system control device includes an AC power supply, a gantry platform, a host computer, and three separate rectifier circuits, filter circuits, a three-phase inverter, a controller, and an isolation drive circuit.

[0097] The switching transistors of the three-phase inverter can be insulated-gate bipolar transistors or metal-oxide-semiconductor field-effect transistors, and the controller can be a digital signal processor or a microcontroller. The current acquisition circuit can be constructed by combining a Hall current sensor with an operational amplifier, or by combining a winding series power resistor with a differential operational amplifier. Its output signal is sent to each controller. The mover displacement detection circuit can be constructed by an encoder followed by a level conversion circuit to output a pulse signal that is sent to each controller. The controllers communicate with each other to transmit information about the three servo motors. Each controller then outputs switching signals for different arms of the inverter based on the information obtained and the control method of this invention. These signals are then used to control the switching action of the power switching transistors in the inverter via isolation drive, thereby realizing cross-coupled sliding mode synchronous control of the gantry system based on the information of the mover part of the beam.

[0098] The basic principle is explained as follows:

[0099] After derivation, neglecting the viscous friction matrix, Coriolis force / centripetal force matrix, and the motion path of the beam mover, and assuming m1=m2=m, cosθ≈0, and sinθ≈θ, the beam deflection dynamic model is as follows:

[0100] (12)

[0101] According to equation (12) and the above definitions of variables, it can be seen that:

[0102] (1) , This represents the resultant acceleration and deceleration force exerted by the dual permanent magnet servo motors on the entire crossbeam. If the crossbeam mover is not in the center position of the crossbeam, This results in the overall resultant force of the crossbeam causing the crossbeam to deflect through the crossbeam mover, leading to synchronization errors between the two motors. Furthermore, the farther the crossbeam mover deviates from the center of the crossbeam, the greater the impact of the overall resultant force of the crossbeam on the synchronization errors of the two motors through the crossbeam mover.

[0103] (2) This indicates that the acceleration and deceleration of the crossbeam mover along the crossbeam direction causes the crossbeam to deflect, resulting in a synchronization error between the two motors. Furthermore, the greater the acceleration and deceleration of the crossbeam mover, the greater the impact of the acceleration and deceleration of the crossbeam mover along the crossbeam direction on the synchronization error between the two motors.

[0104] Define the displacement tracking error e of the dual permanent magnet servo motor mover. i (i=1,2) are as follows:

[0105] (13)

[0106] In the formula: The displacement of the gantry beam is given. (i=1,2) represents the displacement of the mover of the dual permanent magnet servo motor.

[0107] Define the cross-coupling error e of a dual permanent magnet servo motor hi (i=1,2) are as follows:

[0108] (14)

[0109] Where β is the cross-coupling coefficient. When the cross-coupling errors of the dual permanent magnet servo motors converge to zero, the tracking error and synchronization error also converge to zero.

[0110] To achieve zero convergence of both the tracking error and synchronization error of the dual permanent magnet servo motor mover, a sliding surface S was designed. i (i=1,2) are as follows:

[0111] (15)

[0112] Differentiating and transforming equation (15), we get:

[0113] (16)

[0114] (17)

[0115] In the formula:

[0116] (18)

[0117] (19)

[0118] To make the sliding surface converge, let

[0119] (20)

[0120] (twenty one)

[0121] In the formula: the symbolic function sgn(S i The format is as follows:

[0122] (twenty two)

[0123] Substituting equations (20) and (21) into equations (16) and (17), we get:

[0124] (twenty three)

[0125] (twenty four)

[0126] According to Lyapunov's stability theorem, when the following conditions are met... Slippery surface (i=1,2) can converge to zero in a finite amount of time.

[0127] By combining equations (20) and (21), the cross-coupled sliding mode currents of the dual permanent magnet servo motors can be obtained as follows:

[0128] (25)

[0129] in,

[0130] (26)

[0131] According to the analysis in (1) of "Influence Analysis of the Crossbeam Mover on the Synchronous Operation of the Gantry Double Permanent Magnet Linear Motor", in order to eliminate The impact of this item on synchronous displacement error is addressed by employing a current redistribution strategy, which is explained in detail below.

[0132] According to equation (12), we can further substitute the current into it to get:

[0133] (27)

[0134] Let the redistributed cross-coupling sliding mode current be , Before and after current redistribution: (1) the combined thrust of the two motors remains unchanged, (2) the expected generation of a counter-beam deflection term. We can obtain:

[0135] (28)

[0136] (29)

[0137] If equations (28) and (29) hold true at all times, then

[0138] (30)

[0139] in:

[0140] (31)

[0141] According to the analysis in (2) of "Analysis of the Influence of the Beam Mover on the Synchronous Operation of the Gantry Double Permanent Magnet Linear Motor", in order to effectively eliminate Theoretically, the current reconstruction method described above can also be used to address the impact of synchronous displacement errors. However, the mathematical model of an actual gantry system includes the mass, mechanical dimensions, and friction coefficient of various parts. Among these parameters, the mass of each part is relatively easy to measure or observe, while some mechanical dimensions and friction coefficients are difficult to obtain accurately. Because the calculation involves the coordinates of the mover's center of mass on the beam, and the actual geometric structure of the mover on the beam is irregular, the distance d from the mover's center of mass to the center of the rotating bearings at both ends of the beam is difficult to measure or observe. This makes it challenging to eliminate the error using the current reconstruction method. It is difficult to influence the synchronous displacement error.

[0142] To this end, the present invention further proposes a variable gain sliding mode synchronization control strategy. A fuzzy variable gain strategy is constructed by using the net current of the q-axis of the beam mover, the synchronous displacement error of the dual motor movers, and the synchronous speed error. The gain in the sliding mode synchronization control is adjusted by fuzzy adjustment of the acceleration and deceleration motion of the beam mover along the beam direction, thereby further suppressing the synchronous dynamic error of the dual permanent magnet linear motors.

[0143] Based on equation (26), design the variables I1 and I2 in the variable gain sliding mode current:

[0144] (32)

[0145] Where α is the sliding mode variable gain coefficient.

[0146] The absolute value of the net current along the q-axis of the beam mover Absolute value of synchronous displacement error of dual motor movers and absolute value of synchronization speed error The input to the variable gain fuzzy controller is α, and the output is the sliding mode variable gain coefficient. Design 5 fuzzy sets: zero (Z), small (S), medium (M), large (B), and very large (VB); and Three fuzzy sets are designed: small (S), medium (M), and large (B). Corresponding fuzzy input membership functions are designed accordingly. , and like Figure 4 As shown.

[0147] Eight fuzzy sets are defined for α: zero (Z), very small (VS), small (S), medium-small (MS), medium (M), medium-large (MB), large (B), and very large (VB), corresponding to the following outputs: , , , , , , , .

[0148] The fuzzy inference rules are designed as shown in Table 1-5. For the same rule, the smaller of the three premises is used as the operation, and the larger of the different rules within the same fuzzy set is used as the operation, to obtain the membership degree of α. ,For example:

[0149] (33)

[0150] The output α obtained by defuzzifying using the centroid method is shown below:

[0151] (34).

[0152] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A method for cross-coupled sliding mode synchronous control of gantry dual permanent magnet servo motors based on information of the crossbeam mover section, characterized in that, Includes the following steps: (1) Obtain the displacement of the dual-motor mover of the driving beam and the given value of beam displacement Calculate the displacement tracking error e of the dual-motor mover. i , where i=1,2 refer to two permanent magnet servo motors respectively; (2) Calculate the cross-coupling error e of the two motors hi and cross-coupling speed error ; (3) Calculate the sliding surface S i ; (4) Based on the sliding surface S i Calculate the sign function sgn(S) of the sliding surface. i ); (5) Based on the sliding surface S i Sliding surface sign function sgn(S i Given acceleration Cross-coupling speed error And the sliding mode variable gain coefficient α, calculate the sliding mode synchronization intermediate current I. i : (6) Based on the intermediate current I of sliding mode synchronization i Calculate the cross-coupling sliding mode current i smci ; (7) Based on the mass m of the dual-motor mover i , crossbeam mass m h Mass m of the moving part on the crossbeam d , Length L of the crossbeam, Displacement y of the crossbeam mover d and cross-coupled sliding mode current i smci Calculate the cross-coupled sliding mode reconfiguration current i smci0 ; (8) In the cross-coupled sliding mode reconstruction current i smci0 Above, superimposed frictional equivalent current i fi Obtain the q-axis current of the dual motors ; (9) Using vector control to realize the q-axis current of dual motors Closed-loop control.

2. The gantry dual permanent magnet servo motor cross-coupling sliding mode synchronous control method based on crossbeam mover information according to claim 1, characterized in that, In step (1), the displacement tracking error e of the dual-motor mover i The calculation formula is: （1）。 3. The gantry dual permanent magnet servo motor cross-coupling sliding mode synchronous control method based on crossbeam mover information according to claim 1, characterized in that, In step (2), the cross-coupling error e of the dual motors hi The calculation formula is: （2） Where β is the cross-coupling coefficient; For e hi The differential.

4. The gantry dual permanent magnet servo motor cross-coupling sliding mode synchronous control method based on crossbeam mover information according to claim 1, characterized in that, In step (3), the sliding surface S i The calculation formula is: （3） Among them, c i1 c i2 These are the cross-coupling error coefficient and its differential coefficient, respectively.

5. The gantry dual permanent magnet servo motor cross-coupling sliding mode synchronous control method based on crossbeam mover information according to claim 1, characterized in that, In step (4), the sliding surface sign function sgn(S) i The formula for calculating ) is: （4）。 6. The gantry dual permanent magnet servo motor cross-coupling sliding mode synchronous control method based on crossbeam mover information according to claim 1, characterized in that, In step (5), the sliding mode synchronization intermediate current I i The calculation formula is: （5） in, , , , These are the set controller constants.

7. The gantry dual permanent magnet servo motor cross-coupling sliding mode synchronous control method based on crossbeam mover information according to claim 1, characterized in that, In step (6), the cross-coupled sliding mode current i smci The calculation formula is: （6） Where m1 and m2 are the masses of the two permanent magnet servo motors, respectively, and K is the mass of the two permanent magnet servo motors. f1 K f2 The thrust coefficient of the two permanent magnet servo motors is given.

8. The gantry dual permanent magnet servo motor cross-coupling sliding mode synchronous control method based on crossbeam mover information according to claim 1, characterized in that, In step (7), the cross-coupled sliding mode reconfiguration current i smci0 The calculation formula is: （7） For equation (7), we have: （8） in, , m d Let y be the mass of the moving part on the beam. d L represents the displacement along the beam from its left end, where L is the beam length in meters. h The mass of the crossbeam.

9. The gantry dual permanent magnet servo motor cross-coupling sliding mode synchronous control method based on crossbeam mover information according to claim 1, characterized in that, In step (8), the q-axis current of the dual motors The calculation formula is: （9）。 10. The gantry dual permanent magnet servo motor cross-coupling sliding mode synchronous control method based on crossbeam mover information according to claim 1, characterized in that, In step (5), the sliding mode variable gain coefficient α is obtained through fuzzy inference, and its implementation method is as follows: (5.1) The absolute value of the net current e along the q-axis of the beam mover a The absolute value of the synchronous displacement error e of the dual-motor mover p and the absolute value of the synchronization speed error e v As the fuzzy input variable of the variable gain fuzzy controller; where, Design 5 fuzzy sets: zero (Z), small (S), medium (M), large (B), and very large (VB). and Design three fuzzy sets for each: small (S), medium (M), and large (B); and design the corresponding triangular membership functions. , , , , , , , , , , as follows: （10） （11） （12） （13） （14） （15） （16） （17） （18） （19） （20） (5.2) Perform fuzzy inference based on the fuzzy rule table, and set 8 fuzzy sets for α: zero (Z), very small (VS), small (S), medium-small (MS), medium (M), medium-large (MB), large (B), and very large (VB), with the corresponding output being η. αZ η αVS η αS η αMS η αM η αMB η αB η αVB ; The fuzzy rule table includes the following fuzzy rules: （21） In the fuzzy rule table, the same rule takes the smaller value from the three rule premises, and different rules of the same fuzzy set take the larger value, in order to calculate the membership degree corresponding to α. (5.3) The output is obtained by defuzzifying using the centroid method. , where j = Z, VS, S, MS, M, MB, B,VB.

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