Active error compression virtual structure design method based on virtual multiple axes

Abstract

The invention discloses an active error compression virtual structure design method based on virtual multiple axes, and belongs to the technical field of signal tracking and processing. The method comprises the following steps: designing a virtual multi-axis structure; deriving a universal tracking transfer function formula of the virtual multi-axis structure based on the virtual triple-axis structure; analyzing the stability of the physical axis and the virtual axis of the virtual multi-axis structure to obtain constraint conditions; and when the tracking system meets the constraint condition, calculating the tracking error characteristic and the disturbance suppression characteristic of the virtual multi-axis structure, judging whether a tracking error transfer function of the tracking system is met or not, if not, restarting the design, and if yes, ending the design. The method provided by the invention does not depend on additional sensors and increase hardware cost, only error information is utilized, the error suppression characteristic is fused with the multi-axis suppression characteristic, each virtual axis can be flexibly inserted into the system, and the concept of'active error compression 'is provided to improve the tracking precision.

Description

Technical Field

[0001] The present invention belongs to the field of signal tracking and processing, and particularly relates to a method for designing an active error compression virtual structure based on a virtual multi-axis. Background Art

[0002] In the field of optoelectronic tracking systems, although the traditional compound axis structure has a certain tracking accuracy ability, due to its limitations in space and weight, it is difficult to meet the lightweight requirements, resulting in obstacles in applications in the fields of aviation, spacecraft, etc. Therefore, it is urgent to explore high-precision tracking control means for single-stage drive optoelectronic tracking systems that meet the lightweight requirements. At present, without adding hardware devices, a feasible solution is to superimpose a tracking system based on model simulation to construct a virtual compound axis system. In some studies, the virtual compound axis is also called secondary tracking control. Its control principle is the same as that of the conventional compound axis system, and it essentially belongs to a two-dimensional correlation control system, which can effectively improve the tracking accuracy without adding hardware and meeting the lightweight conditions.

[0003] However, although the existing virtual compound axis system has achieved certain results by simulating the compound axis function with software algorithms, its operation depends on error information and input signal information. In actual application scenarios, it is often difficult to obtain input signals, which greatly limits its application scope. At the same time, in order to meet the diverse tracking accuracy requirements in different scenarios, there is an urgent need to design a virtual structure method that can be plugged in and used at any time. Summary of the Invention

[0004] To solve the above technical problems, the present invention provides a method for designing an active error compression virtual structure based on a virtual multi-axis, which can improve the tracking accuracy according to different accuracy requirements. The method does not depend on input signals and additional sensors, and only operates using error information, and can effectively achieve the function of being plugged in and used at any time to improve accuracy. Its error suppression characteristics integrate multi-axis suppression characteristics, effectively improving the tracking performance.

[0005] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] In the first aspect, a method for designing an active error compression virtual structure based on a virtual multi-axis proposed by the present invention includes the following steps:

[0007] Step (1): Design a virtual multi-axis structure, and the virtual multi-axis structure actively senses the change characteristics of the target trajectory based on the active error compression principle, and adjusts the control strategy in real time according to the error information;

[0008] Step (2): Derive the general tracking transfer function formula of the virtual multi-axis structure based on the virtual triple-axis structure;

[0009] Step (3): Analyze the stability of the physical axes and virtual axes of the virtual multi-axis structure to obtain the constraint conditions, and determine whether the tracking system composed of the physical axes, virtual axes, and their respective corresponding controllers, controlled objects, and feedback links satisfies the constraint conditions;

[0010] Step (4): When the tracking system satisfies the constraint conditions, calculate the tracking error characteristics and disturbance rejection characteristics of the virtual multi-axis structure, and determine whether they satisfy the tracking error transfer function of the tracking system. If not, re-execute steps (1)-(3). If satisfied, end the design.

[0011] In a second aspect, a virtual structure design device for active error compression based on a virtual multi-axis proposed by the present invention includes:

[0012] A virtual axis cooperative control module for designing a virtual multi-axis structure, which actively senses the change characteristics of the target trajectory based on the active error compression principle and adjusts the control strategy in real time according to the error information;

[0013] A transfer function derivation module for deriving the general tracking transfer function formula of the virtual multi-axis structure from the virtual triple-axis structure;

[0014] A stability analysis module for analyzing the stability of the physical axes and virtual axes of the virtual multi-axis structure to obtain the constraint conditions, and determining whether the tracking system composed of the physical axes, virtual axes, and their respective corresponding controllers, controlled objects, and feedback links satisfies the constraint conditions;

[0015] A characteristic calculation and judgment module for calculating the tracking error characteristics and disturbance rejection characteristics of the virtual multi-axis structure when the tracking system satisfies the constraint conditions, and determining whether they satisfy the tracking error transfer function of the tracking system. If not, output an instruction to make the virtual axis cooperative control module start working again; if satisfied, output a design completion signal.

[0016] In a third aspect, the present invention provides an electronic device, including: one or more processors; a memory for storing one or more programs; wherein, when the one or more programs are executed by the one or more processors, the one or more processors implement the foregoing virtual structure design method for active error compression based on a virtual multi-axis.

[0017] In a fourth aspect, the present invention provides a computer-readable storage medium, on which executable instructions are stored, and when the instructions are executed by a processor, the processor can implement the foregoing virtual structure design method for active error compression based on a virtual multi-axis.

[0018] The beneficial effects of the present invention are as follows:

[0019] (1)Compared with the existing virtual compound axis, the virtual multi-axis control structure proposed by the present invention does not rely on additional sensors, does not increase the hardware cost, and can be used only with error information;

[0020] (2)The virtual multi-axis system of the present invention can be used as a plug-in control, which can be used immediately after being plugged in, meets different tracking accuracy requirements, and enhances the adaptability of the system;

[0021] (3)The present invention proposes the concept of "active error compression", which improves the tracking accuracy from the virtual structure and provides a new way to improve the performance of the tracking system. Description of the Drawings

[0022] Figure 1 is the control block diagram of a virtual structure design method for active error compression based on virtual multi-axes of the present invention;

[0023] Figure 2 is the schematic diagram of the virtual structure of active error compression based on virtual multi-axes in the present invention;

[0024] Figure 3 is the trajectory tracking comparison curve of virtual compound axis PID, virtual triple axis PID and virtual quadruple axis PID in the present invention when the input is 100 arcseconds;

[0025] Figure 4 is the trajectory tracking error comparison curve of virtual compound axis PID, virtual triple axis PID and virtual quadruple axis PID in the present invention when the input is 100 arcseconds;

[0026] Figure 5 is the error comparison curve of the noise amplification effect of virtual compound axis PID, virtual triple axis PID and virtual quadruple axis PID in the present invention. Detailed Embodiments

[0027] The present invention will be further described below with reference to the drawings and embodiments.

[0028] Based on the basic theory of the compound axis servo system and the relevant conclusions of engineering practice, for a general tracking system that cannot use the compound axis structure, a virtual structure design method for active error compression based on virtual multi-axes is proposed to improve the tracking accuracy, and this method does not rely on additional sensors, does not require information of the input signal, and does not increase the hardware cost. Figure 1 Shown is the control block diagram of the virtual structure design method for active error compression based on virtual multi-axes proposed by the present invention, where, represents the physical axis controlled object, represents the controller of the physical axis, represents the virtual axis controlled object, represents multiple controllers of the virtual axis, Represents the reference trajectory input, Represents the miss distance, Represents the physical axis control input, Represents the system output, Represents the tracking errors of each virtual axis, Represents the control inputs of each virtual axis, Represents the output of the virtual axis. The method specifically includes:

[0029] Step (1): Design a virtual multi-axis structure. The virtual multi-axis structure is based on the principle of active error compression, that is, multiple virtual axes in this structure can actively perceive the change characteristics of the target trajectory and adjust the control strategy in real time according to the error information. At the same time, through the collaborative work of multiple virtual axes, the error amplitude between the actual trajectory and the target trajectory is reduced to achieve high-precision trajectory tracking;

[0030] Step (2): Derive the general tracking transfer function formula of the virtual multi-axis structure based on the virtual triple-axis structure;

[0031] Step (3): Analyze the stability of the physical axis and virtual axis of the virtual multi-axis structure to obtain the constraint conditions, and confirm whether the tracking system composed of the physical axis, virtual axis, their corresponding controllers, controlled objects, and feedback links meets the constraint conditions;

[0032] Step (4): When the tracking system meets the constraint conditions, calculate the tracking error characteristics and disturbance rejection characteristics of the virtual multi-axis structure, and judge whether it meets the tracking error transfer function of the tracking system. If not, re-execute steps (1)-(3). If it meets, end the design.

[0033] The following separately introduces the specific implementation of each step, Figure 2 The figure shows the design schematic diagram of the active error compression virtual structure based on the virtual multi-axis. The initial trajectory tracking error is , and the single physical axis reduces the error by . As the number of virtual axes increases, the error gradually decreases. When the virtual multi-axes act together, the error is . In step (1), design an active error compression virtual structure based on the virtual multi-axis. The controlled object model of the virtual multi-axis structure needs to satisfy:

[0034] ,

[0035] Among them, Represents the controlled object of the virtual axis, Represents the controlled object of the physical axis, , Represents the uncertain difference between the controlled object of the virtual axis and the controlled object of the physical axis.

[0036] In step (2), for the universal tracking transfer function of the virtual multi-axis structure is:

[0037] ,

[0038] where represents the controller of the physical axis, represents the controller of the virtual axis, represents the Laplace operator, represents the output of the system transfer function, represents the input of the system transfer function.

[0039] According to the characteristic polynomial of the above system tracking transfer function can be written as:

[0040] ,

[0041] If is the pole of the system tracking transfer function , then at least one of the following n equations will hold:

[0042] ,

[0043] ,

[0044] ,

[0045] ……

[0046]

[0047] Define the first transfer function as:

[0048] ,

[0049] It is easy to know that the eigenvalues of are part of the eigenvalues of . Because the characteristic polynomial of the single closed-loop system tracking transfer function is and the original single closed-loop system is stable. Therefore the constraint that the eigenvalues of are all located in the left half plane of the

[0050] plane is that all the characteristic roots of

[0051] Define the second transfer function as:

[0052] ,

[0053] It is easy to know that the eigenvalues of are part of the eigenvalues of When the constraints of the above formula are satisfied, all the eigenvalues of are located in the left half-plane of the plane. Therefore,

[0054] .

[0055] Similarly, by successively defining the transfer function , all the eigenvalues of are located in the left half-plane of the

[0056] plane. The constraint is that

[0057] wherein, is the real part of the complex number and represents the position on the complex plane.

[0058] On the basis of ensuring system stability, the tracking characteristics of the active error compression virtual structure design method based on virtual multi-axes are analyzed. Its tracking error characteristics are expressed as:

[0059] ,

[0060] When the system is single-axis driven, its tracking error transfer function is: , and the tracking error transfer function of the virtual multi-axes is less than , achieving an improvement in tracking accuracy. At the same time, the disturbance transfer function and the noise transfer function do not change with the increase of virtual axes, and are respectively:

[0061] .

[0062] In order to more clearly illustrate the advantages of the active error compression virtual structure design method based on virtual multi-axes in the present invention, the following comparative description is made:

[0063] The physical tracking axis and each virtual axis both use PID controllers, and the control variable method is maintained to ensure the objectivity of the comparison.

[0064] First, the effect of the active error compression virtual structure design method based on virtual multiple axes of the present invention is illustrated through simulation comparison. A sine signal with an input amplitude of 100 arcseconds is input, and the results are as Figure 3 shown. It can be seen from the local enlarged view of the trajectory tracking diagram that the tracking effect of the virtual quadruple axis is relatively the best, and the virtual composite axis is relatively the worst. Through Figure 4 it can be more clearly seen the tracking performance effect of the virtual quadruple axis. Therefore, the conclusion is verified that the virtual multiple axis is a plug-and-play method that can improve the tracking accuracy according to requirements.

[0065] Secondly, noise is added to the simulation. Through Figure 5 it is found that the noise will not be amplified as the number of virtual axes of the virtual multiple axis increases.

[0066] On the other hand, the present invention provides an active error compression virtual structure design device based on virtual multiple axes. Each module included therein can implement each step of the foregoing method. Specifically, it includes:

[0067] A virtual axis cooperative control module, which is used to design a virtual multiple axis structure. The virtual multiple axis structure actively senses the change characteristics of the target trajectory based on the active error compression principle, and adjusts the control strategy in real time according to the error information;

[0068] A transfer function derivation module, which is used to derive the general tracking transfer function formula of the virtual multiple axis structure from the virtual triple axis structure;

[0069] A stability analysis module, which is used to analyze the stability of the physical axis and the virtual axis of the virtual multiple axis structure to obtain constraint conditions, and judge whether the tracking system composed of the physical axis, the virtual axis, and their respective corresponding controllers, controlled objects, and feedback links meets the constraint conditions;

[0070] A characteristic calculation and judgment module, which is used to calculate the tracking error characteristics and disturbance suppression characteristics of the virtual multiple axis structure when the tracking system meets the constraint conditions, and judge whether it meets the tracking error transfer function of the tracking system. If it does not meet, an instruction is output to make the virtual axis cooperative control module start working again; if it meets, a design completion signal is output.

[0071] In a third aspect, the present invention provides an electronic device, including: one or more processors; a memory, which is used to store one or more programs; wherein, when the one or more programs are executed by the one or more processors, the one or more processors implement the foregoing active error compression virtual structure design method based on virtual multiple axes.

[0072] Fourthly, the present invention provides a computer-readable storage medium, on which executable instructions are stored. When the instructions are executed by a processor, the processor can implement the foregoing active error compression virtual structure design method based on virtual multi-axis.

[0073] The specific embodiments described above further elaborate on the purpose, technical solution and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A virtual structure design method based on active error compression of virtual multiple axes, characterized in that: The steps include: Step (1): designing a virtual multi-axis structure, wherein the virtual multi-axis structure actively senses the target trajectory change characteristics based on the active error compression principle, and adjusts the control strategy in real time according to the error information; Step (2): Based on the virtual triple-axis structure, a universal tracking transfer function formula of the virtual multi-axis structure is derived; Step (3): Analyze the stability of the physical axis and virtual axis of the virtual multi-axis structure, obtain constraint conditions, and determine whether the tracking system composed of the physical axis, virtual axis and their corresponding controllers, controlled objects and feedback links meets the constraint conditions; Step (4): When the tracking system satisfies the constraints, calculate the tracking error characteristics and disturbance suppression characteristics of the virtual multi-axis structure to determine whether the tracking error transfer function of the tracking system is satisfied. If not, re-execute steps (1) to (3). If satisfied, end the design.

2. The active error compression virtual structure design method based on virtual multiple axes according to claim 1 is characterized in that: In the step (1), the controlled object model of the virtual multi-axis structure satisfies: ， in, , represents the virtual axis controlled object, Indicates the physical axis controlled object, , Indicates the uncertainty difference between the virtual axis controlled object and the physical axis controlled object.

3. The active error compression virtual structure design method based on virtual multiple axes according to claim 2 is characterized in that: In step (2), the universal tracking transfer function formula of the virtual multi-axis structure is: ， in represents the controller of the physical axis, Represents multiple controllers for virtual axes.

4. The active error compression virtual structure design method based on virtual multiple axes according to claim 3 is characterized in that: The constraints in step (3) are: ， When the n-1th virtual axis controller of the virtual multi-axis structure When the above formula is satisfied, the tracking system is determined to be stable, where represents the Laplace operator, represents the universal tracking transfer function The extreme point, is a complex point The real part of , representing the position on the complex plane.

5. The method for designing a virtual structure based on active error compression of virtual multiple axes according to claim 4, characterized in that: The tracking error characteristics of the virtual multi-axis structure when the system is a single-axis drive in step (4) It is expressed as: 。 6. The method for designing a virtual structure based on active error compression of virtual multiple axes according to claim 5, characterized in that: In step (4), the disturbance transfer function and the noise transfer function are respectively: 。 7. The method for designing a virtual structure based on active error compression of virtual multiple axes according to claim 1, characterized in that: In step (4), the tracking error transfer function .

8. An active error compression virtual structure design device based on virtual multi-axis, characterized in that: include: A virtual axis collaborative control module is used to design a virtual multi-axis structure, which actively senses the target trajectory change characteristics based on the active error compression principle and adjusts the control strategy in real time according to the error information; A transfer function derivation module is used to derive a universal tracking transfer function formula of a virtual multi-axis structure from a virtual triple-axis structure; The stability analysis module is used to analyze the stability of the physical axis and virtual axis of the virtual multi-axis structure, obtain the constraint conditions, and determine whether the tracking system composed of the physical axis, virtual axis and their corresponding controllers, controlled objects and feedback links meets the constraint conditions; The characteristic calculation and judgment module is used to calculate the tracking error characteristics and disturbance suppression characteristics of the virtual multi-axis structure when the tracking system meets the constraints, and to judge whether the tracking error transfer function of the tracking system is met. If not, an instruction is output to make the virtual axis collaborative control module restart working; if so, a design completion signal is output.

9. An electronic device, characterized in that: include: one or more processors; A memory for storing one or more programs; When one or more programs are executed by the one or more processors, the one or more processors implement the active error compression virtual structure design method based on virtual multiple axes as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: Executable instructions are stored thereon, and when the instructions are executed by the processor, the processor can implement the active error compression virtual structure design method based on virtual multiple axes as described in any one of claims 1 to 7.

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