Gantry double-drive control method based on dynamic master-slave weight distribution

Abstract

The invention relates to the technical field of intelligent control, in particular to a gantry double-drive control method based on dynamic master-slave weight distribution, which comprises the following steps: constructing a comprehensive error model of dynamic master-slave motion control calculated by master-slave weight factors, and constructing an error dynamic model of a double-drive platform; initial values of estimation parameters of the error dynamic model are set, and initial values of master-slave weight factors of the motor Y1 and the motor Y2 are set; calculating an output value of PID closed-loop control; then performing parameter estimation on the error dynamic model based on PID closed-loop control, and updating an estimated parameter; calculating the estimated value of the passive force and recording the active force based on an error dynamic model; respectively calculating the integral centroid positions of the cross beam and the movable platform; updating a master-slave weight factor; and the updating is repeated until the closed-loop motion is finished. A dynamic master-slave weight distribution method is adopted to continuously adjust the master-slave relation of the Y-axis double motors, asymmetric load disturbance caused by mass center offset is actively compensated, and the synchronization precision of the double motors is effectively improved.

Description

Technical Field

[0001] This invention relates to the field of intelligent control technology, and in particular to a gantry dual-drive control method based on dynamic master-slave weight allocation. Background Technology

[0002] With the rapid development of high-end manufacturing equipment such as precision CNC machine tools, aerospace assembly systems, and semiconductor lithography equipment, the demand for high-precision motion control technology is becoming increasingly urgent, and its importance is becoming more and more prominent. Among them, the gantry dual-drive motion platform has become a key actuator for achieving nanometer-level positioning and multi-axis collaborative operation due to its advantages such as high rigidity and high dynamic response performance. In actual motion, when there is a large load at the end of the platform, the center of mass of the crossbeam shifts in real time as it moves to different positions along the X-axis, resulting in a strong nonlinearity in the load torque distribution of the Y-axis dual motors. Master-slave control is one of the existing dual-motor synchronous control methods. It uses a fixed master motor as a reference signal source to make the slave motor track the state of the master motor. It has the advantages of simple structure and high tolerance for mechanical coupling. However, current research is mainly based on "fixed master and slave", ignoring the fundamental impact of the dynamic shift of the crossbeam's center of mass on the design of the synchronous control law. Under high-speed motion conditions, excessive synchronization error can induce mechanical resonance and even lead to irreversible damage such as guide rail deformation and mechanical fracture.

[0003] Common limitations of existing methods include the contradiction between the static control architecture and the fixed-time-varying dynamic load characteristics, and the insufficient decoupling capability of parameter identification mechanisms for multi-source disturbances. For example, CN110286689B, applicable to a master-slave switching control method for a dual-axis linkage overload electro-hydraulic servo system, changes the driving axis based on specific conditions. For instance, it switches the master-slave relationship during positive / negative movement of the mechanism; during negative movement, the lower cylinder is the driving axis and the upper cylinder is the follower axis; during positive movement, the upper cylinder is the driving axis and the lower cylinder is the follower axis. The master-slave relationship in this scheme is a discontinuous, instantaneous switching process, and the impact and vibration caused by this discontinuous switching affect the system's control performance. Summary of the Invention

[0004] The purpose of this invention is to propose a gantry dual-drive control method based on dynamic master-slave weight allocation. The dynamic master-slave weight allocation method continuously adjusts the master-slave relationship of the two Y-axis motors, actively compensates for asymmetrical load disturbances caused by centroid offset, and effectively improves the synchronization accuracy of the two motors.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] A gantry dual-drive control method based on dynamic master-slave weight allocation is applied to a gantry dual-drive platform device. The gantry dual-drive platform device includes a crossbeam, a moving platform, motor Y1, motor Y2, and motor X. Motors Y1 and Y2 are respectively located on opposite sides of the crossbeam and are used to drive the crossbeam to move along the Y-axis guide rail direction. Motor X is mounted on the crossbeam and is used to drive the moving platform to move along the X-axis direction.

[0007] The method includes the following steps:

[0008] S1: Construct a comprehensive error model for dynamic master-slave motion control calculated with master-slave weight factors, and construct an error dynamic model for the dual-drive platform;

[0009] S2: Set the initial values ​​for the estimation parameters of the error dynamics model. Set the initial values ​​of the master-slave weighting factors for motors Y1 and Y2. ;

[0010] S3: Calculate the output value of the PID closed-loop control. This is used to control motors Y1 and Y2; then, based on PID closed-loop control, parameter estimation is performed on the error dynamics model, and the estimated parameters are updated; based on the error dynamics model, the estimated value of the passive force is calculated and the active force is recorded. ;

[0011] S4: Based on the travel distance of motor X Calculate the overall center of mass positions of the crossbeam and the moving platform respectively;

[0012] S5: Update the master-slave weight factor based on the calculation results of steps S3 and S4;

[0013] S6: Repeat steps S2 to S5 until the closed-loop motion ends.

[0014] Furthermore, the method for constructing the comprehensive error of dynamic master-slave motion control calculated using master-slave weighting factors in step S1 includes:

[0015] Master-slave gain of motors Y1 and Y2 The values ​​are respectively , It is the master-slave weighting factor;

[0016] The tracking error of motor Y1 is The tracking error of motor Y2 is , and These are the actual displacements of motors Y1 and Y2, respectively. It is the desired displacement of the moving platform along the Y-axis;

[0017] Comprehensive error ,in, The range of values ​​is , , ,when At this time, motor Y1 is the driving motor and motor Y2 is the driven motor.

[0018] Furthermore, the error dynamics equation of the dual-drive platform error dynamics model in step S1 is:

[0019] ,

[0020] in, This indicates the actual speeds of motors Y1 and Y2. This represents the desired displacement of motors Y1 and Y2. This represents the desired speeds of motors Y1 and Y2. This represents the desired acceleration of motors Y1 and Y2. Represents the inertia vector matrix. , , , It is the Coulomb friction coefficient matrix. The input vectors of motor Y1 and motor Y2, This indicates a known external disturbance. It is an unknown external disturbance. .

[0021] Furthermore, the relationship between the inertia vector matrix and the viscous damping coefficient matrix satisfies ;

[0022] Viscous damping coefficient matrix .

[0023] Furthermore, in step S3, the method for parameter estimation of the error dynamics model based on PID closed-loop control includes:

[0024] The output formula for PID closed-loop control is: ,in, and It is a scalar control parameter;

[0025] Combining the aforementioned error dynamics equation, we obtain ,in For unknown parameters in the model, , It is a known The matrix, and and satisfy: ;

[0026] Adaptive function The form is An adaptive law was constructed using a discontinuous projection correction strategy. ,in yes The diagonal matrix represents the adaptive learning rate;

[0027] Projection strategy , ,in, It is a definite, known value: , .

[0028] Furthermore, the method for calculating the estimated value of the passive force and recording the active force in step S3 includes:

[0029] Let the estimated value of the passive force in the dynamic equation be... , ,in, , , , It is after adjusting the parameters The estimated corresponding values;

[0030] Closed-loop output value: ,in , which represents the magnitude of the active force in the dynamic equation.

[0031] Furthermore, in step S4,

[0032] The overall center of gravity of the crossbeam is located as follows: ;

[0033] Overall center of gravity position of the moving platform: ;

[0034] in, and These are the masses of the crossbeam and the moving platform on the crossbeam, respectively. That is the movement distance of the X-axis motor. It is the distance between the two Y-axis guide rails.

[0035] Furthermore, the formula for updating the master-slave weight factor in step S5 is as follows:

[0036] .

[0037] A gantry dual-drive platform device is provided, which applies the above-mentioned gantry dual-drive control method based on dynamic master-slave weight allocation. The gantry dual-drive platform device includes a crossbeam, a moving platform, motor Y1, motor Y2, and motor X. Motors Y1 and Y2 are respectively located on opposite sides of the crossbeam and are used to drive the crossbeam to move along the Y-axis guide rail direction. Motor X is mounted on the crossbeam and is used to drive the moving platform to move along the X-axis direction.

[0038] The gantry dual-drive platform also includes a main controller, a PID controller, a displacement sensor, and a weight sensor. The displacement sensor is used to obtain the displacement of the moving platform, and the weight sensor is used to obtain the mass of the crossbeam and the mass of the moving platform.

[0039] The PID controller is used to send control commands to motors Y1, Y2, and X. The master controller stores a comprehensive error model of dynamic master-slave motion control calculated with master-slave weighting factors, as well as an error dynamics model of the dual-drive platform. The master controller is also used to set the initial values ​​of the master-slave weighting factors for motors Y1 and Y2. ;

[0040] The main controller is used to calculate the output value of the PID closed-loop control. It is used to update the estimated parameters, the estimated values ​​of the passive forces, and the active forces. In addition, the overall center of mass and mass of the crossbeam and moving platform are determined, and the master-slave weight factors are updated to adjust the master-slave relationship between motor Y1 and motor Y2.

[0041] The technical solution provided by this invention may include the following beneficial effects:

[0042] This invention can dynamically adjust the master-slave priority weight of the two motors in real time and continuously according to the dynamic position change of the center of mass of the crossbeam. It adopts a dynamic master-slave weight allocation method to continuously adjust the master-slave relationship of the two motors on the Y-axis, actively compensate for the asymmetrical load disturbance caused by the center of mass offset, effectively improve the synchronization accuracy of the two motors, and effectively avoid the impact vibration caused by discontinuous switching, as well as the possible problems such as guide rail deformation and mechanical breakage. Attached Figure Description

[0043] Figure 1 This is a structural schematic diagram of the gantry dual-drive platform device;

[0044] Figure 2 This is the dynamic master-slave motion control process of the gantry dual-drive platform device;

[0045] Figure 3 This is a force diagram of the crossbeam and moving platform of the gantry dual-drive platform device;

[0046] Among them, motor Y1-1, motor Y2-2, motor X-3, guide rail of motor Y1-4, guide rail of motor Y2-5, guide rail of motor X-6, crossbeam-7, moving platform-8, and end effector-9. Detailed Implementation

[0047] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0048] The following is combined with Figures 1 to 3 This invention describes a gantry dual-drive control method based on dynamic master-slave weight allocation, applied to a gantry dual-drive platform device. The gantry dual-drive platform device includes a crossbeam, a moving platform, motors Y1, Y2, and X. Motors Y1 and Y2 are respectively disposed on opposite sides of the crossbeam and are used to drive the crossbeam to move along the Y-axis guide rail direction. Motor X is mounted on the crossbeam and is used to drive the moving platform to move along the X-axis direction.

[0049] The method includes the following steps:

[0050] S1: Construct a comprehensive error model for dynamic master-slave motion control calculated with master-slave weight factors, and construct an error dynamic model for the dual-drive platform;

[0051] S2: Set the initial values ​​for the estimation parameters of the error dynamics model. Set the initial values ​​of the master-slave weighting factors for motors Y1 and Y2. ;

[0052] S3: Calculate the output value of the PID closed-loop control. This is used to control motors Y1 and Y2; then, based on PID closed-loop control, parameter estimation is performed on the error dynamics model, and the estimated parameters are updated; based on the error dynamics model, the estimated value of the passive force is calculated and the active force is recorded. ;

[0053] S4: Based on the travel distance of motor X Calculate the overall center of mass positions of the crossbeam and the moving platform respectively;

[0054] S5: Update the master-slave weight factor based on the calculation results of steps S3 and S4;

[0055] S6: Repeat steps S2 to S5 until the closed-loop motion ends.

[0056] This invention can dynamically adjust the master-slave priority weight of the two motors in real time and continuously according to the dynamic position change of the center of mass of the crossbeam. It adopts a dynamic master-slave weight allocation method to continuously adjust the master-slave relationship of the two motors on the Y-axis, actively compensate for the asymmetrical load disturbance caused by the center of mass offset, effectively improve the synchronization accuracy of the two motors, and effectively avoid the impact vibration caused by discontinuous switching, as well as the possible problems such as guide rail deformation and mechanical breakage.

[0057] Reference Figure 1 and Figure 2 Motors Y1 and Y2 jointly drive the platform's linear motion in the Y direction, and the linear motion of motor X causes the platform to generate linear displacement in the X direction. The method for constructing the comprehensive error of dynamic master-slave motion control calculated using master-slave weighting factors in step S1 of this invention includes:

[0058] These represent the displacements of motors Y1, Y2, and X along their respective guide rails, measured by their respective feedback devices. The desired Y-axis displacement at the end of the platform; These are the desired displacements of motors Y1 and Y2, respectively; gain The values ​​are respectively , This is the master-slave weighting factor, used to measure the master-slave relationship between motor Y1 and motor Y2. The tracking errors of the two motors can be expressed as follows: and .

[0059] Comprehensive error ,in, The range of values ​​is , , It is the displacement error of motor Y1 under the proposed master-slave structure. It is the displacement error of motor Y2 under the proposed master-slave structure. ,when At this time, motor Y1 is the driving motor and motor Y2 is the driven motor.

[0060] The process of establishing the error dynamics model of the dual-drive platform in step S1 of this invention is as follows.

[0061] The dynamic equations for the dual-drive shaft dynamic modeling of the existing gantry dual-drive shaft are as follows:

[0062]

[0063] in, , , These represent the actual displacement, actual velocity, and actual acceleration of the two linear motors with dual drive shafts, respectively; inertia vector matrix. It is diagonal matrix, These are the inertia coefficients of motors Y1 and Y2, respectively; the same viscous damping coefficient matrix. It is also Matrix; This is the Coulomb friction coefficient matrix. Let Y1 and Y2 represent the coefficients of friction, respectively. , That is a column vectors, This represents the relationship between the magnitude of the frictional force of motor Y1 and motor Y2 and their respective speeds, using a continuous and smooth function. It means that among them It is a coefficient used to control smoothness.

[0064] In this invention, the input vectors of the two motors Y1 and Y2 Its value is determined by the closed-loop controllers of motors Y1 and Y2; This indicates a known external disturbance. This refers to an unknown external disturbance. Combining the above dual-drive shaft dynamics equations, the error dynamics equation under the master-slave switching control structure is:

[0065] ,

[0066] in, This indicates the actual speeds of motors Y1 and Y2. This represents the desired displacement of motors Y1 and Y2. This represents the desired speeds of motors Y1 and Y2. This represents the desired acceleration of motors Y1 and Y2. Represents the inertia vector matrix. Represents the damping vector matrix. This represents the inertia vector matrix under the desired acceleration. This represents the damping vector matrix at the desired velocity. It is the Coulomb friction coefficient matrix. The input vectors of motor Y1 and motor Y2, This indicates a known external disturbance. It is an unknown external disturbance. It can be proven that regardless Matrix P is invertible for any value. -1 This is the inverse of matrix P. Matrix P is the dynamic master-slave control structure proposed in this invention. Multiplying the original dual-drive shaft dynamic equations by matrix P yields the error dynamic equations under the master-slave switching control structure.

[0067] For the control system to be stable, the relationship between the inertia vector matrix and the viscous damping coefficient matrix must satisfy... ; Representation matrix The first derivative with respect to time.

[0068] Viscous damping coefficient matrix , Representation matrix The first derivative with respect to time.

[0069] In step S3 of the present invention, the method for parameter estimation of the error dynamics model based on PID closed-loop control includes:

[0070] Combining the comprehensive error function, the output formula for PID closed-loop control is:

[0071]

[0072] in, and It is a scalar control parameter. This is the updated overall error;

[0073] Combining the aforementioned error dynamics equation, we obtain:

[0074]

[0075] in For unknown parameters in the model, In the model, each term is a parameter multiplied by a motion state variable (displacement, velocity, and acceleration). However, the dynamic equations only contain two motion state variables, Y1 and Y2, representing the motor. Therefore, we need to extract the common factor from the equations. The dynamic equations can then be written as Therefore, in the form of It is a known The matrix, and and satisfy:

[0076]

[0077] Adaptive function The form is:

[0078]

[0079] use The estimated values ​​of the dynamic model parameters are represented by the values, and an adaptive law is constructed using a discontinuous projection correction strategy. ,in yes The diagonal matrix represents the adaptive learning rate;

[0080] Projection strategy Defined as:

[0081]

[0082] in, It is a definite, known value: , In step S2, the present invention provides a known model estimation parameter. During algorithm execution, based on existing... By integrating equation (10), the parameter values ​​of the dynamic model can be obtained. .

[0083] The method for dynamic master-slave weight allocation in this embodiment of the invention is as follows.

[0084] Based on the dynamic equations of the dual-drive shaft, the estimated value of the passive force in the dynamic equations is defined as follows: :

[0085]

[0086] in, , , , It is after adjusting the parameters The corresponding values ​​after estimation.

[0087] Combining the output formula of PID closed-loop control, the closed-loop output value under the master-slave switching control structure is obtained:

[0088]

[0089] in, , which represents the magnitude of the active force in the dynamic equation.

[0090] Reference Figure 3 , and These are the masses of the crossbeam and the X-axis moving platform on the crossbeam, respectively. , The guide rail resists the torque that causes rotational motion due to the imbalance of thrust at both ends of the crossbeam; The point is the center point of the beam, and at the same time The point is also the location of the centroid of the beam; and These represent the positions of the center of mass of the beam plus the moving platform as a whole and the center of mass of the moving platform, respectively. That is the movement distance of the X-axis motor. It is the distance between the two Y-axis guide rails.

[0091] In step S4 of this invention, the position of the center of mass of the entire crossbeam and moving platform is... and The value of .

[0092] The overall center of gravity of the crossbeam is located as follows: ;

[0093] Overall center of gravity position of the moving platform: .

[0094] The torque balance equation is:

[0095] .

[0096] in These represent the output values ​​of motors Y1 and Y2 in a dynamic master-slave structure, respectively. To improve the overall accuracy of the platform, especially the synchronization accuracy of the dual drive axes, it is necessary to minimize the tendency for the crossbeam to move. and The values ​​should be as small as possible. Then:

[0097]

[0098] Closed-loop output value formula under master-slave switching control structure ,get:

[0099]

[0100] in These represent the magnitudes of the output thrust of motors Y1 and Y2, respectively. Then, the master-slave weighting factor... for: .

[0101] Reference Figure 1 This invention provides a gantry dual-drive platform device, which applies the aforementioned gantry dual-drive control method based on dynamic master-slave weight allocation. The gantry dual-drive platform device includes a crossbeam, a moving platform, motors Y1-1, Y2-2, and X-3. Motors Y1-1 and Y2-2 are respectively located on opposite sides of the crossbeam-7 and are used to drive the crossbeam-7 to move along the Y-axis guide rail direction. Motor X-3 is installed on the crossbeam-7 and is used to drive the moving platform-8 to move along the X-axis direction, thereby driving the end effector-9.

[0102] The gantry dual-drive platform also includes a main controller, a PID controller, a displacement sensor, and a weight sensor. The displacement sensor is used to obtain the displacement of the moving platform, and the weight sensor is used to obtain the mass of the crossbeam and the mass of the moving platform.

[0103] The PID controller is used to send control commands to motors Y1, Y2, and X. The master controller stores a comprehensive error model of dynamic master-slave motion control calculated with master-slave weighting factors, as well as an error dynamics model of the dual-drive platform. The master controller is also used to set the initial values ​​of the master-slave weighting factors for motors Y1 and Y2. ;

[0104] The main controller is used to calculate the output value of the PID closed-loop control. It is used to update the estimated parameters, the estimated values ​​of the passive forces, and the active forces. In addition, the overall center of mass and mass of the crossbeam and moving platform are determined, and the master-slave weight factors are updated to adjust the master-slave relationship between motor Y1 and motor Y2.

[0105] Other components and operations of the gantry dual-drive control method based on dynamic master-slave weight allocation according to embodiments of the present invention are known to those skilled in the art and will not be described in detail here.

[0106] In the description of this specification, references to terms such as "embodiment," "example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0107] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A gantry dual-drive control method based on dynamic master-slave weight allocation, characterized in that, This invention relates to a gantry dual-drive platform device, which includes a crossbeam, a moving platform, motors Y1, Y2, and X. Motors Y1 and Y2 are located on opposite sides of the crossbeam and are used to drive the crossbeam to move along the Y-axis guide rail direction. Motor X is mounted on the crossbeam and is used to drive the moving platform to move along the X-axis direction. The method includes the following steps: S1: Construct a comprehensive error model for dynamic master-slave motion control calculated with master-slave weight factors, and construct an error dynamic model for the dual-drive platform; S2: Set the initial values ​​for the estimation parameters of the error dynamics model. Set the initial values ​​of the master-slave weighting factors for motors Y1 and Y2. ; S3: Calculate the output value of the PID closed-loop control. This is used to control motors Y1 and Y2; then, based on PID closed-loop control, parameter estimation is performed on the error dynamics model, and the estimated parameters are updated; based on the error dynamics model, the estimated value of the passive force is calculated and the active force is recorded. ; S4: Based on the travel distance of motor X Calculate the overall center of mass positions of the crossbeam and the moving platform respectively; S5: Update the master-slave weight factor based on the calculation results of steps S3 and S4; S6: Repeat steps S2 to S5 until the closed-loop motion ends.

2. The method according to claim 1, characterized in that, The method for constructing the comprehensive error of dynamic master-slave motion control calculated using master-slave weighting factors in step S1 includes: Master-slave gain of motors Y1 and Y2 The values ​​are respectively , It is the master-slave weighting factor; The tracking error of motor Y1 is The tracking error of motor Y2 is , and are the actual displacements of motor Y1 and motor Y2, respectively. It is the desired displacement of the moving platform along the Y-axis; Comprehensive error ,in, The range of values ​​is , , ,when At this time, motor Y1 is the driving motor and motor Y2 is the driven motor.

3. The method according to claim 2, characterized in that, The error dynamics equation of the dual-drive platform error dynamics model in step S1 is: ， in, These are the actual displacements of motors Y1 and Y2, respectively. This indicates the actual speeds of motors Y1 and Y2. This represents the desired displacement of motors Y1 and Y2. This represents the desired speeds of motors Y1 and Y2. This represents the desired acceleration of motors Y1 and Y2. Represents the inertia vector matrix. , , , It is the Coulomb friction coefficient matrix. The input vectors of motor Y1 and motor Y2, This indicates a known external disturbance. It is an unknown external disturbance. .

4. The method according to claim 3, characterized in that, The relationship between the inertia vector matrix and the viscous damping coefficient matrix satisfies ; Viscous damping coefficient matrix .

5. The method according to claim 3, characterized in that, In step S3, the method for parameter estimation of the error dynamics model based on PID closed-loop control includes: The output formula for PID closed-loop control is: ,in, and It is a scalar control parameter; Combining the aforementioned error dynamics equation, we obtain ,in For unknown parameters in the model, , It is a known The matrix, and and satisfy: ; Adaptive function The form is An adaptive law was constructed using a discontinuous projection correction strategy. ,in yes The diagonal matrix represents the adaptive learning rate; Projection strategy , ,in, It is a definite known value: , .

6. The method according to claim 3, characterized in that, The methods for calculating the estimated value of the passive force and recording the active force in step S3 include: Let the estimated value of the passive force in the dynamic equation be... , ,in, , , , It is after adjusting the parameters The estimated corresponding values; Closed-loop output value: ,in , which represents the magnitude of the active force in the dynamic equation.

7. The method according to claim 6, characterized in that, In step S4 The overall center of gravity of the crossbeam is located as follows: ; Overall center of gravity position of the moving platform: ; in, and These are the masses of the crossbeam and the moving platform on the crossbeam, respectively. That is the movement distance of the X-axis motor. It is the distance between the two Y-axis guide rails.

8. The method according to claim 6, characterized in that, The formula for updating the master-slave weight factor in step S5 is as follows: .

9. A gantry dual-drive platform device, characterized in that, The method for gantry dual-drive control based on dynamic master-slave weight allocation according to any one of claims 1-8 is described below; the gantry dual-drive platform device includes a crossbeam, a moving platform, motor Y1, motor Y2 and motor X, motor Y1 and motor Y2 are respectively disposed on opposite sides of the crossbeam and are used to drive the crossbeam to move along the Y-axis guide rail direction; motor X is installed on the crossbeam and is used to drive the moving platform to move along the X-axis direction. The gantry dual-drive platform also includes a main controller, a PID controller, a displacement sensor, and a weight sensor. The displacement sensor is used to obtain the displacement of the moving platform, and the weight sensor is used to obtain the mass of the crossbeam and the mass of the moving platform. The PID controller is used to send control commands to motors Y1, Y2, and X. The master controller stores a comprehensive error model of dynamic master-slave motion control calculated with master-slave weighting factors, as well as an error dynamics model of the dual-drive platform. The master controller is also used to set the initial values ​​of the master-slave weighting factors for motors Y1 and Y2. ; The main controller is used to calculate the output value of the PID closed-loop control. It is used to update the estimated parameters, the estimated values ​​of the passive forces, and the active forces. In addition, the overall center of gravity position and mass of the crossbeam and moving platform are updated, and the master-slave weight factor is adjusted to adjust the master-slave relationship between motor Y1 and motor Y2.

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