High-precision turntable intelligent control method and equipment based on improved ESO

Abstract

The invention relates to the technical field of rotary table control, in particular to a high-precision rotary table intelligent control method and device based on improved ESO, and the method comprises the steps: constructing a mathematical model of a rotary table motor, and deriving a transfer function of the motor; respectively acquiring current and angle data of a turntable motor; building a turntable control system, wherein the three-axis turntable control system is composed of a current loop, a position loop and an ESO-based virtual control law; designing a virtual control law based on ESO; and superposing the designed ESO virtual control law output to the turntable current loop and position loop output, and embedding a control algorithm into a processing module of a turntable upper industrial personal computer to complete the intelligent control of the turntable. According to the method, a transfer function of a motor is established, a virtual control law based on improved ESO is designed on the basis of an extended state observation theory, cooperative control over the rotary table is achieved with PID control, and high-precision pointing of the rotary table is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of turntable control, and in particular relates to a high-precision turntable intelligent control method and device based on improved ESO. Background Art

[0002] The turntable is a complex mechatronics integrated device that performs physical simulation and analog testing in the automotive, shipborne, and aerospace fields. It plays a key role in the development of various automotive, shipborne, and aerospace products. It can simulate various attitude and angular motions, reproduce its various dynamic characteristics during motion, and repeatedly test the performance of the guidance system, control system, and corresponding components of automotive, shipborne, and aerospace products to obtain sufficient test data, and redesign and improve the system based on the data to meet the performance index requirements of the overall design.

[0003] Active disturbance rejection control is a control strategy that does not rely on an accurate model and has strong anti-disturbance performance. It observes and compensates disturbances other than the series integral type through an extended state observer (ESO). Therefore, the disturbance observation accuracy of the ESO determines the compensation effect of the disturbance. However, when the classic ESO is applied on a simulation turntable, there are problems such as large compensation and limited anti-disturbance performance, which limits its performance and application scenarios. Summary of the invention

[0004] The present invention provides a high-precision turntable intelligent control method and device based on improved ESO, which is used to solve the defects of large compensation amount and limited anti-interference performance when ESO is applied on a simulation turntable in the prior art, and improve the turntable position tracking accuracy.

[0005] The present invention provides a high-precision turntable intelligent control method based on improved ESO, comprising the following steps: Construct the mathematical model of the turntable motor to obtain the transfer function of the turntable motor; Collect the current and angle data of the turntable motor respectively; Build a turntable control system, including the turntable current loop and position loop as well as the virtual control law based on ESO; Determine the virtual control law based on ESO; The output of the virtual control law based on ESO is superimposed on the turntable current loop and position loop output, and the control algorithm is embedded in the processing module of the turntable host industrial computer to complete the turntable control.

[0006] According to a high-precision turntable intelligent control method based on improved ESO provided by the present invention, the transfer function of the turntable motor is expressed as follows: 1) The voltage balance of the motor is: (1) in,v m is the control voltage on the motor armature, E is the back EMF of the motor, i m is the armature current of the motor, R m is the motor armature resistance, L m is the motor armature inductance, d represents the differential symbol, t represents the time variable; 2) The back electromotive force of the motor is: (2) in, k e is the motor back EMF constant, is the motor speed; 3) The torque equation and torque balance equation of the motor are: The torque equation of the motor is: (3) in, is the torque of the motor, k m is the torque constant of the torque motor; The torque balance equation of the motor is: (4) in, J is the rotor and load inertia of the torque motor, F is the friction torque and disturbance torque acting on the torque motor, Represents the first derivative of the motor speed; Performing Laplace transform on equations (1) to (4) yields: (5) In the formula, s is the Laplace operator.

[0007] According to a high-precision turntable intelligent control method based on improved ESO provided by the present invention, respectively collecting the current and angle data of the turntable motor includes: collecting the current data of the motor through a sensor, and collecting the angle data of the motor through a circular grating.

[0008] According to a high-precision turntable intelligent control method based on improved ESO provided by the present invention, the turntable control system comprises: The angular displacement and motor current of the turntable are collected in real time, and the instructions are converted into the corresponding angular displacement and motor current through the transfer function. The current closed-loop and position closed-loop control of the turntable are realized through PID. The PID control is expressed as follows: (6) In the formula, k p ，k i ，k d are the proportional, integral and differential parameters of PID, k is the sampling time, e is the error of the control quantity of the turntable, e ( k )yes k The error of the control quantity of the turntable at the moment, U ( k ) is the turntable control output.

[0009] According to a high-precision turntable intelligent control method based on improved ESO provided by the present invention, the turntable control system adopts an industrial computer for unified control and management to complete real-time control calculation, control unit management and human-computer interaction.

[0010] According to a high-precision turntable intelligent control method based on improved ESO provided by the present invention, the determination of the virtual control law based on ESO includes: 1) Observe the motor status data through ESO, (7) In the formula, z 1 ( k )and z 2 ( k )yes k The estimate of the system state variables at time , z 3 ( k ) is the system k The sum of disturbances at time, y ( k ) is the system k The measured angular position at time, k represents the sampling time, for k The system output error at that moment is u ( k -1) is the system k The input of ESO at time -1 is different from that of ordinary observers. u ( k ) is delayed by one beat before entering the extended state observer. is the gain constant, , and is an adjustable parameter, and is a nonlinear parameter, where fal It can be expressed as: (8) Among them, gn is the sign function; 2) Determine the motor speed control law, (9) in a 1 Speed ​​status v The control law of x 2 is the backstepping error between the speed control law and the speed state; 3) Determine the virtual control law based on ESO: (10) in k 1 is the positive feedback gain, is the adaptive model compensation term, which is used to improve the tracking performance of the system. is the robust feedback term; 4) Output of virtual control law based on ESO u for: (11) in g is the mapping function, g = (z 1 ,y)=sign(z 1 )y,u a is the model compensation term, u s is the robust feedback term used to adjust the error of the turntable system, z 1 , z 2 is an estimate of the system state variables, y is the actual output of the system.

[0011] The present invention also provides an electronic device, comprising a processor, a motion control card, a memory and a control program based on the improved ESO that can be run thereon, and when the processor executes the program, it implements any of the above-mentioned high-precision turntable intelligent control methods based on the improved ESO.

[0012] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the high-precision turntable intelligent control method based on the improved ESO as described in any one of the above is implemented.

[0013] The present invention also provides a computer program product, comprising a computer program, which, when executed by a processor, implements any of the above-mentioned high-precision turntable intelligent control methods based on improved ESO.

[0014] Compared with the prior art, the present invention superimposes the virtual control law output of the extended state observer on the turntable current loop PID output and the position loop PID output. This fusion enables the ESO to not only act as a state observer, but also directly participate in the control process of the system. The virtual control law output of the improved ESO is superimposed on the output of the PID controller to optimize the control performance of the system, so that it can better cope with the nonlinearity, time-varying and uncertainty in the system. The beneficial effects of the present invention are: 1. By adopting the improved ESO and PID collaborative control method, high-precision positioning control of the turntable is achieved, and the positioning accuracy and stability of the system are improved.

[0015] 2. The improved ESO delays the control signal by one beat before entering the extended state observer, improving the observation performance and effectively realizing the estimation and compensation of friction; 3. Through the improved ESO to observe the turntable, the motor speed control law and motor torque virtual control law are used to enable the system to better adapt to complex working environments and changing conditions; 4. The designed virtual control law combines the model compensation term and the robust feedback term, which improves the system's anti-interference ability to parameter changes and disturbances, and enhances the system's robustness and robustness; 5. By establishing the transfer function of the motor, the virtual control law of the improved ESO was designed, and the coordinated control of the turntable was achieved with PID, which improved the control accuracy and anti-interference ability of the turntable. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 is a flow chart of a high-precision turntable intelligent control method based on improved ESO provided by an embodiment of the present invention; Figure 2 It is a block diagram of the structure of the high-precision turntable intelligent control based on the improved ESO provided by an embodiment of the present invention; Figure 3 is a position tracking curve graph provided by an embodiment of the present invention; Figure 4It is a local enlarged view of position tracking provided by an embodiment of the present invention; Figure 5 is a position tracking error curve diagram provided by an embodiment of the present invention; Figure 6 is a local enlarged diagram of the position tracking error provided by an embodiment of the present invention; FIG. 7 ( a ) is a Matlab statistical result diagram of an angular position error signal under an angular position error PID control mode provided by an embodiment of the present invention; FIG. 7( b ) is a Matlab statistical result diagram of the angular position error signal under the ADRC control mode provided in an embodiment of the present invention; FIG. 7 ( c ) is a Matlab statistical result diagram of the angular position error signal under the improved ESO+PID control mode provided by an embodiment of the present invention; Figure 8 It is a schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] This embodiment proposes a high-precision turntable intelligent control method based on improved ESO to improve the turntable position tracking accuracy. On the basis of improved ESO, a method for improving the performance of an intelligent turntable combining ESO virtual control with traditional PID control is proposed. By establishing the transfer function of the motor and based on the extended state observation theory, a virtual control law based on improved ESO is designed to achieve coordinated control of the turntable with PID control to ensure high-precision pointing of the turntable. Figure 1 This is a flow chart of this embodiment. The embodiment is described below in conjunction with the accompanying drawings and specific implementation methods: Step 1, construct the mathematical model of the turntable motor to deduce the transfer function of the motor, and analyze the mathematical models of the turntable motor, driver and current loop; Furthermore, the transfer function corresponding to step 1 is expressed as follows: Step 1.1 Analyze the voltage balance of the motor: (1) in, v m is the control voltage on the motor armature, E is the back electromotive force of the motor, i mis the armature current of the motor, R m is the motor armature resistance, L m is the motor armature inductance, d represents the differential sign, and t represents the time variable.

[0020] Step 1.2 Analyze the back electromotive force of the motor: (2) in, k e is the motor back EMF constant, is the motor speed.

[0021] Step 1.3 Analyze the torque equation and torque balance equation of the motor. The torque equation is expressed as follows: (3) in, is the torque of the motor, k m is the torque constant of the torque motor; the torque balance equation of the motor can be expressed as follows: (4) in, J is the rotor and load inertia of the torque motor, F is the friction torque and disturbance torque acting on the torque motor, Represents the first-order derivative of the motor speed; Laplace transform of equations (1) to (4) yields (5) In the formula, s is the Laplace operator.

[0022] Step 2, respectively collecting the current and angle data of the turntable motor, collecting the motor current through the sensor, and collecting the angle through the circular grating; Step 3: Build the turntable control system: The three-axis turntable control system consists of a current loop, a position loop, and an ESO-based virtual control law, and is uniformly controlled and managed by an industrial computer to complete real-time control calculations, control unit management, and human-computer interaction. Furthermore, the three-axis turntable control system corresponding to step 3 is represented by the current loop and position loop as follows: The angular displacement and motor current of the turntable are collected in real time, and the instructions are converted into the corresponding angular displacement and motor current through the transfer function. The current closed-loop and position closed-loop control of the turntable are realized through PID. The PID control can be expressed as follows: (6) In the formula, k p ，ki ，k d are the proportional, integral and differential parameters of PID, k is the sampling time, e is the error of the control quantity of the turntable, e(k) is the error of the control quantity of the turntable at time k, and U(k) is the output of the control quantity of the turntable.

[0023] Step 4: Design virtual control law based on ESO: Design virtual control law of motor speed and motor torque according to motor data observed by ESO. The control structure diagram is as follows: Figure 2 As shown; Furthermore, the virtual control law corresponding to ESO in step 4 is expressed as follows: Step 4.1: First observe the motor data through ESO (7) In the formula, z 1 (k) and z 2 (k) is the estimate of the system state variables at time k, z 3 (k) is the total disturbance of the system at time k, y(k) is the measured value of the angular position of the system at time k, k represents the sampling time, is the system output error at time k, u(k-1) is the input of the ESO at time k-1. Unlike ordinary observers, u(k) is delayed by one beat before entering the extended state observer. is the gain constant, , and is an adjustable parameter, and is a nonlinear parameter, where fal can be expressed as: (8) Among them, sign is the sign function; Step 4.2, design the motor speed control law (9) in a 1 is the virtual control law of the speed state v; x 2 is the backstepping error between the speed virtual control law and the speed state.

[0024] Step 4.2, design the motor torque virtual control law: (10) in k 1 is the positive feedback gain, α 2a is the adaptive model compensation term, which is used to improve the tracking performance of the system.α 2s is the robust feedback term.

[0025] Step 4.3, Output of the virtual control law based on ESO u Can be designed as (11) in g is the mapping function, u a is the model compensation term, u s is the robust feedback term used to adjust the error of the turntable system, z 1、 z 2 is an estimate of the system state variables and y is the actual output of the system.

[0026] Step 5, superimpose the virtual control law output of the designed ESO on the turntable current loop and position loop output, and embed the control algorithm into the processing module of the turntable host industrial computer to complete the intelligent control of the turntable.

[0027] The following is a specific example to verify the high-precision control method of the turntable based on the improved ESO of the present invention. An intelligent control simulation model based on the improved ESO is built in Simulink, in which the motor armature resistance R m The motor armature inductance is 2.6Ω. L m is 0.1mH, the torque constant of the motor k m The motor back electromotive force constant is 0.00767N•m / A. k e is 0.00767V•s / rad, the rotor and load inertia of the torque motor J The transfer function of the turntable motor is constructed based on the above parameters.

[0028] The control structure block diagram of this embodiment is as follows Figure 2 When the angle setting value is a sine signal, the position tracking curve of the system is as follows: Figure 3 , Figure 4 As shown, the position tracking error curve is as follows Figure 5 , Figure 6 The figure compares the improved ESO+PID control effect of this embodiment with PID control and ADRC control. Figure 5 The position tracking error curve in the figure is shown in Figure 7. Matlab is used to perform statistics on the angular position error signals under three control modes: angular position error PID control, ADRC control, and improved ESO+PID control. The results are shown in Figure 7(a), Figure 7(b), and Figure 7(c), respectively.

[0029] It can be seen that compared with PID control and ADRC control, the maximum value, minimum value, peak-to-peak value, mean value, median value and RMS value of the turntable angular position error of the improved ESO+PID control are significantly reduced. Among them, the maximum error of the angular position is 0.02275 rad, and the root mean square error is only 0.002059 rad. It can be seen that the method of the present invention effectively improves the control accuracy of the turntable.

[0030] Figure 8 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 8 As shown, the electronic device may include: a processor, a motion control card, a memory, a communications interface, and a system bus. The processor, the motion control card, the memory, the communications interface, and the system bus communicate with each other through the system bus. The processor uses the program code and data in the memory to execute the high-precision turntable intelligent control method based on the improved ESO. The motion control card receives a large amount of external turntable monitoring operation data and feedback information in real time, and outputs motion control instructions to the turntable. The communication interface communicates with other external devices.

[0031] In addition, the logic instructions in the above-mentioned memory can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program code.

[0032] On the other hand, the present invention also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the high-precision turntable intelligent control method based on improved ESO provided by the above methods.

[0033] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the high-precision turntable intelligent control method based on improved ESO provided by the above methods.

[0034] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Those of ordinary skill in the art may understand and implement it without creative effort.

[0035] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-precision turntable intelligent control method based on improved ESO, characterized in that: The following steps are involved: Construct the mathematical model of the turntable motor to obtain the transfer function of the turntable motor; Collect the current and angle data of the turntable motor respectively; Build a turntable control system, including the turntable current loop and position loop as well as the virtual control law based on ESO; Determine the virtual control law based on ESO; The output of the virtual control law based on ESO is superimposed on the turntable current loop and position loop output, and the control algorithm is embedded in the processing module of the turntable host industrial computer to complete the turntable control.

2. According to claim 1, the high-precision turntable intelligent control method based on improved ESO is characterized in that: The transfer function of the turntable motor is expressed as follows: 1) The voltage balance of the motor is: (1) in, v m is the control voltage on the motor armature, E is the back EMF of the motor, i m is the armature current of the motor, R m is the motor armature resistance, L m is the motor armature inductance, d represents the differential symbol, t represents the time variable; 2) The back electromotive force of the motor is: (2) in, k e is the motor back EMF constant, is the motor speed; 3) The torque equation and torque balance equation of the motor are: The torque equation of the motor is: (3) in, is the torque of the motor, k m is the torque constant of the torque motor; The torque balance equation of the motor is: (4) in, J is the rotor and load inertia of the torque motor, F is the friction torque and disturbance torque acting on the torque motor, Represents the first derivative of the motor speed; Performing Laplace transform on equations (1) to (4) yields: （5） In the formula, s is the Laplace operator.

3. According to claim 1, the high-precision turntable intelligent control method based on improved ESO is characterized in that: Collecting the current and angle data of the turntable motor separately includes: collecting the current data of the motor through a sensor, and collecting the angle data of the motor through a circular grating.

4. According to claim 1, the high-precision turntable intelligent control method based on improved ESO is characterized in that: The turntable control system comprises: The angular displacement and motor current of the turntable are collected in real time, and the instructions are converted into the corresponding angular displacement and motor current through the transfer function. The current closed-loop and position closed-loop control of the turntable are realized through PID. The PID control is expressed as follows: （6） In the formula, k p ，k i ，k d are the proportional, integral and differential parameters of PID, k is the sampling time, e is the error of the control quantity of the turntable, e ( k )yes k The error of the control quantity of the turntable at the moment, U ( k ) is the turntable control output.

5. The system of the high-precision turntable intelligent control method based on improved ESO according to claim 4 is characterized in that: The turntable control system adopts an industrial computer for unified control and management to complete real-time control calculation, control unit management and human-computer interaction.

6. According to claim 1, the high-precision turntable intelligent control method based on improved ESO is characterized in that: The determining of the ESO-based virtual control law includes: 1) Observe the motor status data through ESO, （7） In the formula, z 1( k )and z 2( k )yes k The estimate of the system state variables at time , z 3( k ) is the system k The sum of disturbances at time, y ( k ) is the system k The measured angular position at time, k represents the sampling time, for k The system output error at the moment, u ( k -1) is the system k The input of ESO at time -1 is different from that of ordinary observers. u ( k ) is delayed by one beat before entering the extended state observer. is the gain constant, , and is an adjustable parameter, and is a nonlinear parameter, where fal It can be expressed as: （8） Among them, gn is the sign function; 2) Determine the motor speed control law, （9） in a 1 is the speed state v The control law of x 2 is the backstepping error between the speed control law and the speed state; 3) Determine the virtual control law based on ESO: （10） in k 1 is a positive feedback gain, is the adaptive model compensation term, which is used to improve the tracking performance of the system. is the robust feedback term; 4) Output of virtual control law based on ESO u for: （11） in g is the mapping function, g = (z 1 ,y)=sign(z 1 )y,u a is the model compensation term, u s is the robust feedback term used to adjust the error of the turntable system, z 1. z 2 is the estimate of the system state variables, y is the actual output of the system.

7. An electronic device, comprising a processor, a motion control card, a memory and a control program for improving ESO that can be run thereon, characterized in that: When the processor executes the program, the high-precision turntable intelligent control method based on improved ESO as described in any one of claims 1 to 5 is implemented.

8. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the high-precision turntable intelligent control method based on improved ESO as claimed in any one of claims 1 to 5 is implemented.

9. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the high-precision turntable intelligent control method based on improved ESO as claimed in any one of claims 1 to 5 is implemented.

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