A cantilever plate-shell vibration control method combining MFC and variable frequency TMD

Abstract

This invention provides a vibration reduction control method for cantilever shell structures combining MFC (Multi-Functional Control Unit) and variable frequency TMD (Variable Frequency Drive), comprising the following steps: establishing a finite element model of the cantilever shell structure using ANSYS; placing the variable frequency TMD at the location of maximum deformation; and arranging the MFC according to optimization criteria; identifying the natural frequency of the variable frequency TMD; applying current to the coil of the variable frequency TMD using a current source; adjusting the stiffness of the variable frequency TMD to ensure its vibration frequency matches the vibration frequency of the cantilever shell structure, thereby reducing the overall vibration of the cantilever shell structure; developing an MCS (Multi-Screen Adaptive Control) algorithm to control the MFC to generate driving force; adjusting the MFC driving force by changing the applied voltage to reduce the local vibration response of the cantilever shell structure; and using the variable frequency TMD to perform multi-directional and multi-dimensional vibration reduction on the cantilever shell structure. This invention uses both variable frequency TMD and MFC to jointly reduce the vibration of the cantilever shell structure, achieving multi-directional and multi-dimensional vibration reduction control.

Description

Technical Field

[0001] The present invention relates to the technical field of structural engineering and structural vibration control, and in particular to a cantilever plate shell vibration reduction control method combining MFC and variable frequency TMD. Background Art

[0002] With the continuous development and progress of science and technology, the development of modern architecture tends to be large-scale, lightweight and highly reinforced. In order to meet the needs of people's lives and production, modern buildings are mostly high-rise, super-high-rise and underground large-scale building facilities, which puts forward higher requirements for civil engineering workers.

[0003] However, the structure will vibrate under external excitation. When the vibration frequency of the structure is the same as the external excitation frequency, resonance will occur. In this case, it often does not take a large external excitation amplitude to cause the structure itself to vibrate greatly. At the least, it will cause discomfort to the personnel inside the structure, and at the worst, it will affect the service condition of the structure or even cause damage, resulting in safety accidents and casualties. In fact, these loads are very common in damaging structures.

[0004] For cantilever plate-shell structures, one end is a fixed support that does not produce axial, vertical displacement and rotation, and the other end is a free end. The thickness of the plate-shell structure is much smaller than its length and width, so the main consideration is the vibration in the thickness direction, such as the wings of aircraft, balcony panels in civil buildings, solar panels, etc. Structural vibration control is divided into three parts: passive control, semi-active control, and active control. Passive control mainly achieves the purpose of reducing the structural vibration response by adding substructures to the structure to enhance the structural energy dissipation capacity, such as tuned mass dampers (TMDs). However, after long-term use, the actual structure will slowly change its natural frequency due to steel corrosion, fatigue aging, etc. At this time, the natural frequency of the originally set TMD is no longer consistent with the natural frequency of the structure. When the structure resonates, its ability to absorb structural energy is weakened or even completely disappears, and the purpose of reducing structural vibration cannot be achieved. Summary of the invention

[0005] In view of this, the purpose of the present invention is to design a vibration reduction control method combining macro fiber composite material (MFC) and variable frequency TMD, apply semi-active control and active control, apply smart materials and new composite materials together in the vibration reduction control of civil engineering structures, reduce the vibration response of cantilever plate-shell structures, and solve the problems of vibration response and excessive noise of cantilever plate-shell structures during operation.

[0006] The present invention applies semi-active control and active control, and applies intelligent materials and new composite materials together to the vibration reduction control of civil engineering structures. Semi-active control is a more effective control method with adjustment capability based on passive control. Compared with passive control, semi-active control is more adaptable and flexible. Compared with semi-active control, active control has better environmental adaptability and can also have a greater vibration reduction effect when the structural vibration characteristics change. However, active control requires more external energy input than semi-active control.

[0007] Smart materials are new materials that can sense external conditions and thus change their own characteristics. In structural vibration control, these smart materials are often used to make energy-consuming devices with adjustable parameters, such as dampers made of magnetorheological fluids whose damping force changes with the intensity of the magnetic field. Combining the advantages of adjustable performance of smart materials, smart materials are combined with TMDs in passive control to form variable frequency TMDs. Active control research is conducted on piezoelectric materials in smart materials to make macrofiber composite materials (MFCs) with good driving performance, wide operating frequency band, light weight, fast response, no electromagnetic interference, low energy consumption, good electromechanical coupling characteristics, and easy control.

[0008] The present invention provides a cantilever plate shell vibration reduction control method combining MFC and variable frequency TMD, comprising the following steps:

[0009] S1: using ANSYS to establish a finite element model of the cantilever plate-shell structure, and determining the maximum deformation point of the cantilever plate-shell structure;

[0010] S2: The variable frequency TMD is arranged at the maximum deformation point of the cantilever plate-shell structure, and the MFC is arranged on the cantilever plate-shell structure according to the optimal arrangement criterion of the controllable / observable Gramian matrix;

[0011] The present invention places the variable frequency TMD at the maximum deformation position where the vibration response of the controlled structure is large, that is, the top free end, and adheres the macro fiber composite material MFC to the cantilever plate shell structure according to the optimization layout principle to form a vibration reduction control system for the cantilever plate shell structure;

[0012] S3: Identify the natural frequency of the variable frequency TMD, use a current source to apply current to the coil of the variable frequency TMD, adjust the stiffness of the variable frequency TMD, make the vibration frequency of the variable frequency TMD consistent with the vibration frequency of the cantilever plate-shell structure, and reduce the overall vibration of the cantilever plate-shell structure;

[0013] S4: Write an MCS adaptive control algorithm to control the MFC to generate driving force, change the input voltage to adjust the driving force of the MFC, and reduce the local vibration response of the cantilever plate-shell structure; cooperate with the variable frequency TMD to perform multi-directional and multi-dimensional vibration reduction on the cantilever plate-shell structure.

[0014] Furthermore, the method for determining the maximum deformation point of the cantilever plate shell structure in step S1 includes:

[0015] ANSYS is used to establish a finite element model of the cantilever plate and shell structure, and modal analysis is performed on the finite element model to obtain the frequencies and vibration modes of the first three modes, and to extract the mass stiffness matrix of the cantilever plate and shell structure. The internal balance reduction method is used to reduce the order of the cantilever plate and shell structure calculation model, and the low-order modes that account for a large proportion of the controlled structural modes are retained. The reduced-order calculation model is obtained according to the accuracy requirements, and the optimization layout criterion based on the controllable / observable Gramian matrix is ​​used to take the minimum control energy and the maximum sensor energy as the optimization goals.

[0016] Furthermore, the method of arranging the MFC in step S2 includes:

[0017] Based on the optimization layout criterion of the controllable / observable Gramian matrix, the minimum control energy and the maximum sensor energy are taken as the optimization targets, the layout positions of the MFC driver plate and the sensor plate on the cantilever plate shell structure are determined, and the MFC driver plate and the MFC sensor plate are pasted to the corresponding positions of the cantilever plate shell structure. The MFC sensor plate is connected to the input end of the real-time simulation system. When the cantilever plate shell structure is vibrated by external excitation, the vibration response of the corresponding position of the real-time plate shell structure is measured by the MFC sensor plate, and the measured data is transmitted to the real-time simulation system; the output end of the real-time simulation system is connected to the input end of the high-voltage amplifier, and the data of the real-time simulation system is transmitted to the high-voltage amplifier after being calculated by the MCS adaptive control algorithm in the computer; the output end of the high-voltage amplifier is connected to the MFC driver plate, and the high-voltage amplifier provides voltage for the MFC, and the driving force of the MFC driver plate is changed in real time by adjusting the voltage, thereby reducing the local vibration of the plate shell structure and forming a closed-loop control.

[0018] Furthermore, the variable frequency TMD in step S3 includes: a spring, an additional mass block, a magnetorheological elastomer intelligent material and a magnetic circuit structure that changes the external magnetic field. By changing the current passed into the variable frequency TMD, the shear modulus of the magnetorheological elastomer can be changed, thereby changing the stiffness of the variable frequency TMD.

[0019] Furthermore, the method of identifying the natural frequency of the variable frequency TMD in step S3 includes:

[0020] The first three frequencies of the cantilever plate-shell structure are identified by combining Hilbert-Huang and natural excitation techniques and compared with the results calculated by ANSYS.

[0021] Furthermore, the method of making the vibration frequency of the variable frequency TMD consistent with the vibration frequency of the cantilever plate shell structure in step S3 includes:

[0022] By adjusting the magnitude of the current passed through the coil of the variable frequency TMD, the vibration frequency of the variable frequency TMD is ensured to be consistent with the vibration frequency of the cantilever plate shell structure, thereby absorbing the energy in the vibration to the greatest extent and reducing the overall vibration of the cantilever plate shell structure.

[0023] Further, the method of writing the MCS adaptive control algorithm in step S4 includes:

[0024] The motion equation of the cantilever plate-shell structure is established and transformed into the state-space equation; the MCS adaptive control algorithm of the cantilever plate-shell structure mathematical model is constructed in matlab / simulink.

[0025] Furthermore, the method of controlling the MFC to generate driving force in step S4 includes:

[0026] The vibration state of the cantilever plate-shell structure is fed back to the MCS algorithm through the MFC sensor sheet, the optimal output of the MFC is calculated in the computer, and the optimal output is converted into a voltage signal, which is transmitted to the high-voltage amplifier by the real-time processing system. The voltage required for the optimal output of the MFC is applied to the MFC through the high-voltage amplifier, and the inverse piezoelectric effect of the MFC is used to convert the control signal received in the form of electrical signal into mechanical energy to act on the cantilever plate-shell structure, thereby controlling the local vibration of the cantilever plate-shell structure.

[0027] The present invention also provides a computer-readable storage medium having a computer program stored thereon, and when the program is executed by a processor, the steps of the cantilever plate shell vibration reduction control method combining MFC and variable frequency TMD described above are implemented.

[0028] The present invention also provides a computer device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the steps of the cantilever plate shell vibration reduction control method combining MFC and variable frequency TMD as described above are implemented.

[0029] The present invention has the following characteristics:

[0030] 1. From the working principle of TMD, it can be known that only when its natural frequency is consistent with the natural frequency of the structure, can the vibration of the structure of this order frequency be suppressed. However, the natural frequency of the actual structure will change to a certain extent during use, and the control ability will be greatly weakened at this time, and the purpose of reducing structural vibration cannot be achieved. The semi-active control of the variable frequency TMD by controlling the current size is more effective, and has adjustment ability and better robustness;

[0031] 2. The macrofiber composite material (MFC) used in the present invention has the advantages of wide operating frequency band, good driving performance, good temperature stability, low energy consumption, good electromechanical coupling, small additional mass and additional stiffness, and has little effect on the controlled structure;

[0032] 3. The present invention arranges the MFC driver slices according to the optimized arrangement rule, which is more reasonable than the general arrangement method and has a better control effect.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] The present invention adopts variable frequency TMD and MFC to jointly reduce the vibration of the cantilever plate shell structure. The variable frequency TMD reduces the overall vibration of the cantilever plate shell structure, and the MFC reduces the local vibration of the cantilever plate shell structure, thereby realizing multi-directional and multi-dimensional vibration reduction control of the cantilever plate shell structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the following detailed description of the preferred embodiment.The drawings are only for the purpose of illustrating the preferred embodiments and are not to be construed as limiting the invention.

[0036] In the attached picture:

[0037] Figure 1 It is a flow chart of a vibration reduction control method of a cantilever plate-shell structure combining MFC and variable frequency TMD of the present invention;

[0038] Figure 2 A schematic diagram of the structure of a computer device according to an embodiment of the present invention;

[0039] Figure 3 This is a control flow chart of the combination of variable frequency TMD and MFC according to an embodiment of the present invention;

[0040] Figure 4 It is the MFC control working roadmap of the embodiment of the present invention;

[0041] Figure 5 This is a schematic diagram of the power of the cantilever plate shell structure of the MFC embodiment of the present invention.

[0042] Attached photos Figure 4 The mark in the middle is:

[0043] 1. MFC driver chip; 2. MFC sensor chip; 3. Real-time processing system; 4. Computer; 5. High-voltage amplifier. DETAILED DESCRIPTION

[0044] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and products consistent with some aspects of the present disclosure as detailed in the appended claims.

[0045] The terms used in this disclosure are for the purpose of describing specific embodiments only and are not intended to limit the disclosure. The singular forms of "a", "said" and "the" used in this disclosure and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0046] It should be understood that although the terms first, second, third, etc. may be used in the present disclosure to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present disclosure, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0047] The embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

[0048] The embodiment of the present invention provides a cantilever plate shell vibration reduction control method combining MFC and variable frequency TMD, see Figure 1 As shown, the following steps are included:

[0049] S1: using ANSYS to establish a finite element model of the cantilever plate-shell structure, and determining the maximum deformation point of the cantilever plate-shell structure;

[0050] The method for determining the maximum deformation point of the cantilever plate shell structure comprises:

[0051] ANSYS is used to establish a finite element model of the cantilever plate-shell structure, and a modal analysis is performed on the finite element model to obtain the frequencies and vibration modes of the first three modes, and to extract the mass stiffness matrix of the cantilever plate-shell structure; the internal balance order reduction method is used to reduce the order of the cantilever plate-shell structure calculation model, and the low-order modes that account for a large proportion of the controlled structure modes are retained. The reduced-order calculation model is obtained according to the accuracy requirements, and the minimum control energy and the maximum sensor energy are used as the optimization goals through the optimization layout criterion based on the controllable / observable Gramian matrix;

[0052] S2: The variable frequency TMD is arranged at the maximum deformation point of the cantilever plate-shell structure, and the MFC is arranged on the cantilever plate-shell structure according to the optimal arrangement criterion of the controllable / observable Gramian matrix;

[0053] In the embodiment of the present invention, the variable frequency TMD is placed at the maximum deformation position where the vibration response of the controlled structure is large, that is, the top free end, and the macro fiber composite material MFC is pasted on the cantilever plate shell structure according to the optimization layout criteria to form a vibration reduction control system of the cantilever plate shell structure;

[0054] The method for arranging the MFC comprises:

[0055] See also Figure 4 As shown, based on the optimization layout criterion of the controllable / observable Gramian matrix, the minimum control energy and the maximum sensor energy are taken as the optimization goals, the layout positions of the MFC driver sheet and the sensor sheet on the cantilever plate shell structure are determined, and the MFC driver sheet 1 and the MFC sensor sheet 2 are pasted to the corresponding positions of the cantilever plate shell structure. The MFC sensor sheet is connected to the input end of the real-time simulation system 3. When the cantilever plate shell structure is vibrated by external excitation, the vibration response of the corresponding position of the real-time plate shell structure is measured by the MFC sensor sheet 2, and the measured data is transmitted to the real-time simulation system 3; the output end of the real-time simulation system 3 is connected to the input end of the high-voltage amplifier 5, and the data of the real-time simulation system 3 is transmitted to the high-voltage amplifier 5 after being calculated by the MCS adaptive control algorithm in the computer 4; the output end of the high-voltage amplifier 5 is connected to the MFC driver sheet 1, and the high-voltage amplifier 5 provides voltage for the MFC, and the driving force of the MFC driver sheet 1 is changed in real time by adjusting the voltage, thereby reducing the local vibration of the cantilever plate shell structure to form a closed-loop control;

[0056] See also Figure 5 The figure shows the force of the MFC on the cantilever plate shell structure according to the embodiment of the present invention;

[0057] S3: Identify the natural frequency of the variable frequency TMD, use a current source to apply current to the coil of the variable frequency TMD, adjust the stiffness of the variable frequency TMD, make the vibration frequency of the variable frequency TMD consistent with the vibration frequency of the cantilever plate-shell structure, and reduce the overall vibration of the cantilever plate-shell structure;

[0058] The variable frequency TMD comprises: a spring, an additional mass block, a magnetorheological elastomer intelligent material and a magnetic circuit structure for changing an external magnetic field. By changing the current passed into the variable frequency TMD, the shear modulus of the magnetorheological elastomer can be changed, thereby changing the stiffness of the variable frequency TMD.

[0059] The method for identifying the natural frequency of the variable frequency TMD comprises:

[0060] The first three frequencies of the cantilever plate-shell structure are identified by combining Hilbert-Huang and natural excitation techniques and compared with the results calculated by ANSYS.

[0061] The method for making the vibration frequency of the variable frequency TMD consistent with the vibration frequency of the cantilever plate shell structure comprises:

[0062] By adjusting the magnitude of the current in the coil of the variable frequency TMD, the vibration frequency of the variable frequency TMD is ensured to be consistent with the vibration frequency of the cantilever plate shell structure, thereby absorbing the energy in the vibration to the greatest extent and reducing the overall vibration of the cantilever plate shell structure;

[0063] S4: Write an MCS adaptive control algorithm to control the MFC to generate driving force, change the input voltage to adjust the driving force of the MFC, and reduce the local vibration response of the cantilever plate-shell structure; cooperate with the variable frequency TMD to perform multi-directional and multi-dimensional vibration reduction on the cantilever plate-shell structure.

[0064] The method for writing the MCS adaptive control algorithm comprises:

[0065] The motion equation of the cantilever plate-shell structure is established and transformed into the state-space equation; the MCS adaptive control algorithm of the cantilever plate-shell structure mathematical model is constructed in matlab / simulink.

[0066] The method for controlling the MFC to generate driving force comprises:

[0067] The vibration state of the cantilever plate-shell structure is fed back to the MCS algorithm through the MFC sensor sheet, the optimal output of the MFC is calculated in the computer, and the optimal output is converted into a voltage signal, which is transmitted to the high-voltage amplifier by the real-time processing system. The voltage required for the optimal output of the MFC is applied to the MFC through the high-voltage amplifier, and the inverse piezoelectric effect of the MFC is used to convert the control signal received in the form of electrical signal into mechanical energy to act on the cantilever plate-shell structure, thereby controlling the local vibration of the cantilever plate-shell structure.

[0068] See also Figure 3 The figure shows the control flow of the combination of variable frequency TMD and MFC according to an embodiment of the present invention.

[0069] The embodiments of the present invention have the following characteristics:

[0070] 1. From the working principle of TMD, it can be known that only when its natural frequency is consistent with the natural frequency of the structure, can the vibration of the structure of this order frequency be suppressed. However, the natural frequency of the actual structure will change to a certain extent during use, and the control ability will be greatly weakened at this time, and the purpose of reducing the vibration of the structure cannot be achieved. However, the semi-active control of the variable frequency TMD by controlling the current size in this embodiment is more effective, and has adjustment ability and better robustness;

[0071] 2. The macrofiber composite material (MFC) used in this embodiment has the advantages of a wide operating frequency band, good driving performance, good temperature stability, low energy consumption, good electromechanical coupling, small additional mass and additional stiffness, and has little effect on the controlled structure;

[0072] 3. This embodiment uses an optimized layout rule to arrange the MFC driver slices, which is more reasonable than the general layout method and has a better control effect.

[0073] 4. The embodiment of the present invention adopts variable frequency TMD and MFC to jointly reduce the vibration of the cantilever plate shell structure. The variable frequency TMD reduces the overall vibration of the cantilever plate shell structure, and the MFC reduces the local vibration of the cantilever plate shell structure, thereby realizing multi-directional and multi-dimensional vibration reduction control of the cantilever plate shell structure.

[0074] The embodiment of the present invention further provides a computer device, Figure 2 is a schematic diagram of the structure of a computer device provided by an embodiment of the present invention; see the accompanying drawings Figure 2 As shown, the computer device includes: an input device 23, an output device 24, a memory 22 and a processor 21; the memory 22 is used to store one or more programs; when the one or more programs are executed by the one or more processors 21, the one or more processors 21 implement the cantilever plate shell vibration reduction control method combining MFC and variable frequency TMD as provided in the above embodiment; wherein the input device 23, the output device 24, the memory 22 and the processor 21 can be connected by a bus or other means, Figure 2 The example of connecting through bus is taken in the following.

[0075] The memory 22 is a readable and writable storage medium of a computing device, and can be used to store software programs and computer executable programs, such as the program instructions corresponding to the cantilever plate shell vibration reduction control method combined with MFC and variable frequency TMD described in the embodiment of the present invention; the memory 22 can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system and at least one application required for a function; the data storage area can store data created according to the use of the device, etc.; in addition, the memory 22 can include a high-speed random access memory, and can also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device; in some instances, the memory 22 can further include a memory remotely arranged relative to the processor 21, and these remote memories can be connected to the device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0076] The input device 23 may be used to receive input digital or character information, and to generate key signal input related to user settings and function control of the device; the output device 24 may include a display device such as a display screen.

[0077] The processor 21 executes various functional applications and data processing of the device by running the software programs, instructions and modules stored in the memory 22, that is, realizes the cantilever plate shell vibration reduction control method combining the above-mentioned MFC and variable frequency TMD.

[0078] The computer device provided above can be used to execute the active control method of controlling MFC drive by the MCS algorithm provided in the above embodiment, and has corresponding functions and beneficial effects.

[0079] The embodiment of the present invention also provides a storage medium containing computer executable instructions, which are used to execute the cantilever plate shell vibration control method combined with MFC and variable frequency TMD as provided in the above embodiment when executed by a computer processor. The storage medium is any of various types of memory devices or storage devices, and the storage medium includes: installation media, such as CD-ROM, floppy disk or tape device; computer system memory or random access memory, such as DRAM, DDR RAM, SRAM, EDO RAM, Rambus RAM, etc.; non-volatile memory, such as flash memory, magnetic media (such as hard disk or optical storage); registers or other similar types of memory elements, etc.; the storage medium may also include other types of memory or combinations thereof; in addition, the storage medium may be located in the first computer system in which the program is executed, or may be located in a different second computer system, the second computer system is connected to the first computer system via a network (such as the Internet); the second computer system may provide program instructions to the first computer for execution. The storage medium includes two or more storage media that can reside in different locations (for example, in different computer systems connected via a network). The storage medium can store program instructions (for example, specifically implemented as a computer program) that can be executed by one or more processors.

[0080] Of course, the storage medium containing computer executable instructions provided in an embodiment of the present invention is not limited to the cantilever plate shell vibration reduction control method combining MFC and variable frequency TMD as described in the above embodiment, and can also execute related operations in the cantilever plate shell vibration reduction control method combining MFC and variable frequency TMD provided in any embodiment of the present invention.

[0081] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

[0082] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A cantilever plate shell vibration control method combining MFC and variable frequency TMD, characterized in that: The following steps are involved: S1: using ANSYS to establish a finite element model of the cantilever plate-shell structure, and determining the maximum deformation point of the cantilever plate-shell structure; S2: The variable frequency TMD is arranged at the maximum deformation point of the cantilever plate-shell structure, and the MFC is arranged on the cantilever plate-shell structure according to the optimal arrangement criterion of the controllable / observable Gramian matrix; S3: Identify the natural frequency of the variable frequency TMD, use a current source to apply current to the coil of the variable frequency TMD, adjust the stiffness of the variable frequency TMD, make the vibration frequency of the variable frequency TMD consistent with the vibration frequency of the cantilever plate-shell structure, and reduce the overall vibration of the cantilever plate-shell structure; S4: Write an MCS adaptive control algorithm to control the MFC to generate driving force, change the input voltage to adjust the driving force of the MFC, and reduce the local vibration response of the cantilever plate-shell structure; cooperate with the variable frequency TMD to perform multi-directional and multi-dimensional vibration reduction on the cantilever plate-shell structure.

2. The cantilever plate shell vibration reduction control method combining MFC and variable frequency TMD according to claim 1 is characterized in that: The method for determining the maximum deformation point of the cantilever plate shell structure in step S1 includes: ANSYS is used to establish a finite element model of the cantilever plate and shell structure, and modal analysis is performed on the finite element model to obtain the frequencies and vibration modes of the first three modes, and to extract the mass stiffness matrix of the cantilever plate and shell structure. The internal balance reduction method is used to reduce the order of the cantilever plate and shell structure calculation model, and the low-order modes that account for a large proportion of the controlled structural modes are retained. The reduced-order calculation model is obtained according to the accuracy requirements, and the optimization layout criterion based on the controllable / observable Gramian matrix is ​​used to take the minimum control energy and the maximum sensor energy as the optimization goals.

3. The cantilever plate shell vibration reduction control method combining MFC and variable frequency TMD according to claim 1 is characterized in that: The method for arranging the MFC in step S2 includes: Based on the optimization layout criterion of the controllable / observable Gramian matrix, the minimum control energy and the maximum sensor energy are taken as the optimization targets, the layout positions of the MFC driver plate and the sensor plate on the cantilever plate shell structure are determined, and the MFC driver plate and the MFC sensor plate are pasted to the corresponding positions of the cantilever plate shell structure. The MFC sensor plate is connected to the input end of the real-time simulation system. When the cantilever plate shell structure is vibrated by external excitation, the vibration response of the corresponding position of the real-time plate shell structure is measured by the MFC sensor plate, and the measured data is transmitted to the real-time simulation system; the output end of the real-time simulation system is connected to the input end of the high-voltage amplifier, and the data of the real-time simulation system is transmitted to the high-voltage amplifier after being calculated by the MCS adaptive control algorithm in the computer; the output end of the high-voltage amplifier is connected to the MFC driver plate, and the high-voltage amplifier provides voltage for the MFC, and the driving force of the MFC driver plate is changed in real time by adjusting the voltage, thereby reducing the local vibration of the plate shell structure and forming a closed-loop control.

4. The cantilever plate shell vibration reduction control method combining MFC and variable frequency TMD according to claim 1 is characterized in that: The variable frequency TMD in step S3 includes: a spring, an additional mass block, a magnetorheological elastomer smart material and a magnetic circuit structure that changes the external magnetic field. By changing the current passed into the variable frequency TMD, the shear modulus of the magnetorheological elastomer can be changed, thereby changing the stiffness of the variable frequency TMD.

5. The cantilever plate and shell vibration reduction control method combining MFC and variable frequency TMD according to claim 1 is characterized in that: The method of identifying the natural frequency of the variable frequency TMD in step S3 includes: The first three frequencies of the cantilever plate-shell structure are identified by combining Hilbert-Huang and natural excitation techniques and compared with the results calculated by ANSYS.

6. The cantilever plate and shell vibration reduction control method combining MFC and variable frequency TMD according to claim 1 is characterized in that: The method of making the vibration frequency of the variable frequency TMD consistent with the vibration frequency of the cantilever plate shell structure in step S3 includes: By adjusting the magnitude of the current passed through the coil of the variable frequency TMD, the vibration frequency of the variable frequency TMD is ensured to be consistent with the vibration frequency of the cantilever plate shell structure, thereby absorbing the energy in the vibration to the greatest extent and reducing the overall vibration of the cantilever plate shell structure.

7. The cantilever plate and shell vibration reduction control method combining MFC and variable frequency TMD according to claim 1 is characterized in that: The method for writing the MCS adaptive control algorithm in step S4 includes: The motion equation of the cantilever plate-shell structure is established and transformed into the state-space equation; the MCS adaptive control algorithm of the cantilever plate-shell structure mathematical model is constructed in matlab / simulink.

8. The cantilever plate and shell vibration reduction control method combining MFC and variable frequency TMD according to claim 1 is characterized in that: The method of controlling the MFC to generate driving force in step S4 comprises: The vibration state of the cantilever plate-shell structure is fed back to the MCS algorithm through the MFC sensor sheet, the optimal output of the MFC is calculated in the computer, and the optimal output is converted into a voltage signal, which is transmitted to the high-voltage amplifier by the real-time processing system. The voltage required for the optimal output of the MFC is applied to the MFC through the high-voltage amplifier, and the inverse piezoelectric effect of the MFC is used to convert the control signal received in the form of electrical signal into mechanical energy to act on the cantilever plate-shell structure, thereby controlling the local vibration of the cantilever plate-shell structure.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the cantilever plate shell vibration reduction control method combining MFC and variable frequency TMD as described in any one of claims 1 to 8 are implemented.

10. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the steps of the cantilever plate shell vibration reduction control method combining MFC and variable frequency TMD as described in any one of claims 1 to 8 are implemented.

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