Control method, system, device and medium for active vibration isolation system of precision equipment

Abstract

The embodiment of the application provides a control method, system, equipment and medium of a precision equipment active vibration isolation system, and belongs to the cross field of precision equipment vibration control and intelligent control. By constructing a new type of vector type direct barrier function, the physical hard constraint of the system output is equivalently converted into the boundedness requirement of the variable in the transformation space, which is more direct and universal. A distributed fuzzy logic system network is used to parallelly approximate the unknown nonlinear dynamics appearing in the backstepping design, and by adjusting the square of the weight vector norm online, the calculation complexity is greatly reduced. In the recursive design of the backstepping control law, the hyperbolic tangent function and the projection operator are integrated, so that the amplitude of the virtual control law and the actual control law has a priori known upper bound, thereby satisfying the input saturation constraint, and the internal saturation design of the controller is realized.

Description

Technical Field

[0001] This invention relates to the field of cross-disciplinary technology of vibration control and intelligent control for precision equipment, and specifically to a control method, system, equipment and medium for an active vibration isolation system for precision equipment. Background Technology

[0002] With the rapid development of high-end manufacturing, integrated circuits, biomedicine, and other fields, the requirements for the working environment of precision equipment (such as scanning electron microscopes, atomic force microscopes, and precision CNC machine tools) are becoming increasingly stringent. Even minor mechanical vibrations can lead to decreased processing accuracy, reduced product yield, or even direct equipment failure. Active vibration isolation systems, by detecting vibrations in real time and applying reverse control forces, have become a key technology for ensuring the stability of the working environment for precision equipment.

[0003] However, the control design of active vibration isolation systems for precision equipment faces multiple challenges:

[0004] Strong nonlinearity and uncertainty: Damping and stiffness in vibration isolation systems often exhibit nonlinear characteristics, and system parameters change with load, service life, and ambient temperature, making accurate modeling difficult. Furthermore, the system is also affected by unknown external disturbances such as those from the ground and human operation.

[0005] Strict output constraints: For safety and performance reasons, the displacement of the vibration isolation platform must be strictly limited to a safe physical range. For example, excessive displacement may cause precision equipment to collide with surrounding structures or cause actuators to exceed their effective stroke, resulting in irreversible damage.

[0006] Inherent input saturation: The actuators in the system (such as voice coil motors and piezoelectric actuators) have a physical upper limit to their output force and cannot provide infinite control force. If the influence of this saturation nonlinearity is ignored in the controller design, it can easily lead to system performance degradation or even instability.

[0007] High requirements for control performance: It is necessary not only to ensure the stability of the system, but also to ensure that the system output can quickly and accurately track the desired reference trajectory (usually zero displacement or a specific trajectory) and have good dynamic quality.

[0008] Traditional control methods, such as classic PID control, perform well in handling linear and time-invariant systems, but struggle to effectively address nonlinearities, constraints, and uncertainties simultaneously. While existing backstepping control, adaptive control, and methods based on barrier Lyapunov functions have made theoretical progress, practical applications often suffer from complex controller structures, heavy computational burdens, or failure to simultaneously address output constraints and input saturation. Therefore, there is an urgent need for a practical and robust control scheme that can systematically solve all of these challenges. Summary of the Invention

[0009] The purpose of this invention is to provide a control method, system, device, and medium for an active vibration isolation system for precision equipment. This system can ensure that the displacement output of the vibration isolation platform does not violate preset constraints and that the control input is always within the physical saturation limit of the actuator, without relying on a precise system model. Furthermore, it is known from prior knowledge that the system is consistently bounded for all closed-loop signals and achieves excellent reference signal tracking performance.

[0010] To achieve the above objectives, embodiments of the present invention provide a control method for an active vibration isolation system for precision equipment, comprising:

[0011] Establish a rigorous feedback nonlinear model for the active vibration isolation system;

[0012] Construct a barrier function related to the displacement of the vibration isolation platform in the active vibration isolation system, so as to transform the physical output constraint of the displacement of the vibration isolation platform into the bounded control objective of the barrier function;

[0013] A fuzzy logic system is used to approximate the unknown nonlinear vector function in the strictly feedback nonlinear model.

[0014] Based on the backstepping method, and combining the hyperbolic tangent function and the projection operator, virtual control law and actual control law are recursively designed to ensure that the control command is always within the physical saturation limit of the actuator in the active vibration isolation system. In particular, by introducing the hyperbolic tangent function and using the projection operator to perform bounded correction on the parameter estimates of the fuzzy logic system, the amplitude of each component of the virtual control law and the actual control law has a priori determined upper bound, thereby satisfying the input saturation constraint of the active vibration isolation system.

[0015] The design employs an adaptive law for parameters to update the parameter estimates of the fuzzy logic system online, and utilizes a projection operator to ensure the boundedness of the parameter estimates during the update process.

[0016] Optionally, the strictly feedback nonlinear model is expressed as:

[0017] ;

[0018] ;

[0019] ;

[0020] In the formula, The system state vector is composed of the states of multiple vibration isolation units. To control the input vector, For the output vector, Given a known, non-singular control gain matrix. For an unknown continuous nonlinear vector function, Given a time-varying unknown disturbance vector, the output constraint is defined as follows: ,in, Represents the individual inequalities of vector elements. Let the lower bound constraint vector be... This is the upper bound constraint vector.

[0021] Optionally, the barrier function is as follows:

[0022] ;

[0023] In the formula, For the output of the active vibration isolation system, and These are the lower and upper bounds of the output, respectively.

[0024] Optionally, a fuzzy logic system can be used to approximate the unknown nonlinear vector function. Its approximate form is:

[0025] ;

[0026] In the formula, For the ideal weight vector, For fuzzy basis function vectors, The approximation error is bounded.

[0027] Optional, virtual control law The components are:

[0028] ;

[0029] In the formula, To control the gain, These are adjustable positive design parameters. For error variables, The parameter norm estimate is obtained through the adaptive law with projection. For fuzzy basis function vectors, It includes known coupling terms and the differential term of the reference signal. It is the hyperbolic tangent function.

[0030] Optional, actual control law No. The components are:

[0031] ;

[0032] In the formula, For the control gain function, These are adjustable positive design parameters. For the first The error variable of the step, The parameter norm estimate is obtained through the adaptive law with projection. For fuzzy basis function vectors, It is the hyperbolic tangent function.

[0033] Optionally, the parameter estimates can be updated online according to the following formula:

[0034] ;

[0035] In the formula, This is the parameter estimate for the Kth iteration. Sampling time, It is an adaptive function. For projection operators, For adaptive gain.

[0036] Secondly, the present invention also provides a control system for an active vibration isolation system for precision equipment, comprising:

[0037] The model building unit is used to build a strictly feedback nonlinear model of the active vibration isolation system.

[0038] Function construction unit, used to construct barrier functions so that output constraints are transformed into boundedness requirements of the barrier functions;

[0039] The function approximation unit is used to approximate the unknown nonlinear vector function in the strictly feedback nonlinear model using a fuzzy logic system.

[0040] The control law design unit is used to design bounded virtual and actual control laws by combining the backstepping method, hyperbolic tangent function and projection operator. By introducing the hyperbolic tangent function and combining it with the projection operator to perform bounded correction on the parameter estimates of the fuzzy logic system, the amplitude of each component of the virtual and actual control laws has a priori known upper bound, thereby satisfying the input saturation constraint of the active vibration isolation system.

[0041] The parameter update unit is used to design the parameter adaptive law, update the parameter estimate online, and use the projection operator to ensure the boundedness of the parameter estimate.

[0042] Thirdly, the present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of the control method for the above-described active vibration isolation system for precision equipment.

[0043] Fourthly, the present invention also provides a storage medium storing a computer program thereon, wherein the computer program, when executed by a processor, implements the steps of the control method for the above-described active vibration isolation system for precision equipment.

[0044] Through the above technical solution, a novel vector-type direct barrier function is constructed to equivalently transform the physical hard constraints of the system output into boundedness requirements of variables in the transformation space. This method is more direct and universal than the traditional barrier Lyapunov function. Secondly, a distributed fuzzy logic system network is used to approximate the unknown nonlinear dynamics encountered in the backstepping design in parallel, and the computational complexity is significantly reduced by adjusting only the square of the norm of the weight vector online. Then, in the recursive design of the backstepping control law, the hyperbolic tangent function and the projection operator are integrated, so that the amplitudes of the virtual control law and the final actual control law have a priori known upper bounds, thus naturally satisfying the input saturation constraint and realizing the "intrinsic saturation" design of the controller. Finally, by constructing a Lyapunov function composed of a logarithmic hyperbolic cosine function and parameter estimation error, and utilizing the key properties of the projection operator, it is rigorously proven that all signals in the closed-loop system are uniformly and ultimately bounded, ensuring that the output constraint is never violated and that tracking performance is excellent.

[0045] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0046] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings:

[0047] Figure 1 This is a flowchart illustrating the implementation of a control method for an active vibration isolation system for precision equipment, as provided in an embodiment of the present invention.

[0048] Figure 2 This is a schematic diagram of the structure of an active vibration isolation system provided in an embodiment of the present invention;

[0049] Figure 3 This is a schematic diagram of the control system of an active vibration isolation system for precision equipment provided in an embodiment of the present invention;

[0050] Figure 4 This is a schematic diagram of the hardware structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0051] Various embodiments of this disclosure will be described more fully in the following detailed description. This disclosure may have various embodiments, and adjustments and changes may be made therein. However, it should be understood that there is no intention to limit the various embodiments of this disclosure to the specific embodiments disclosed herein, but rather this disclosure should be understood to cover all adjustments, equivalents, and / or alternatives falling within the spirit and scope of the various embodiments of this disclosure.

[0052] In the following, the terms “comprising” or “may include”, which may be used in various embodiments of this disclosure, indicate the presence of the disclosed functions or operations and do not limit the addition of one or more functions or operations. Furthermore, as used in various embodiments of this disclosure, the terms “comprising,” “having,” and their cognates are intended only to indicate a specific feature, number, step, operation, or combination of the foregoing and should not be construed as primarily excluding the presence of one or more other features, numbers, steps, operations, or combinations of the foregoing, or the possibility of adding one or more features, numbers, steps, operations, or combinations of the foregoing.

[0053] In various embodiments of this disclosure, the expression "or" or "at least one of A and / or B" includes any combination or all combinations of the words listed simultaneously. For example, the expression "A or B" or "at least one of A and / or B" may include A, may include B, or may include both A and B.

[0054] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0055] See Figure 1 The diagram shows a flowchart of a control method for an active vibration isolation system for precision equipment in a specific embodiment, including the following execution steps:

[0056] Step 100: Establish a strict feedback nonlinear model of the active vibration isolation system.

[0057] Specifically, the dynamic model of the vibration isolation system is normalized into a multi-input multi-output strict feedback system in the following vector form, that is, the strict feedback nonlinear model is expressed as:

[0058] ;

[0059] ;

[0060] ;

[0061] In the formula, The system state vector is composed of the states of multiple vibration isolation units. To control the input vector, For the output vector, Given a known, non-singular control gain matrix. For an unknown continuous nonlinear vector function, Given a time-varying unknown disturbance vector, the output constraint is defined as follows: ,in, Represents the individual inequalities of vector elements. Let the lower bound constraint vector be... This is the upper bound constraint vector. Preferably, Displacement of the vibration isolation platform (system output) ), Represents platform speed. Higher-order states can represent internal states related to actuator dynamics.

[0062] In one specific embodiment, the structure of the active vibration isolation system is as follows: Figure 2 As shown, the system includes a vibration isolation platform for supporting precision equipment; a sensor module comprising displacement and velocity sensors for real-time detection of the platform's displacement and velocity signals; and an actuator module, such as a throttle valve for air-bearing vibration damping, a voice coil motor, or a piezoelectric actuator, for applying active control force to the platform based on control signals. The controller module, at its core a bounded adaptive tracking controller based on a fuzzy logic system, receives sensor signals and outputs bounded control signals to the actuator module. The process of outputting the bounded control signals is described in [reference needed]. Figure 1 The control method implementation process of the precision equipment active vibration isolation system is shown.

[0063] Step 101: Construct a barrier function related to the displacement of the vibration isolation platform in the active vibration isolation system, so as to transform the physical output constraint of the displacement of the vibration isolation platform into the bounded control objective of the barrier function.

[0064] Specifically, the barrier function is as follows:

[0065] ;

[0066] In the formula, For the output of the active vibration isolation system, and These are the lower and upper bounds of the output, respectively.

[0067] In one specific implementation, to address the output constraints in vector form, this application constructs a vector-valued barrier function. , its first Each component is defined as:

[0068]

[0069] This mapping is a differential homeomorphism within the constrained domain. This property is crucial because it guarantees the invertibility of the transformation and the... The stability can be uniquely deduced from the original output. Stability and constraint satisfaction. For Taking the derivative, we get:

[0070]

[0071] in, It is a positive definite diagonal matrix, thus avoiding control over singularities.

[0072] Step 102: Use a fuzzy logic system to approximate the unknown nonlinear vector function in the strictly feedback nonlinear model.

[0073] Specifically, a fuzzy logic system is used to approximate an unknown nonlinear vector function. Its approximate form is:

[0074] ;

[0075] In the formula, For the ideal weight vector, For fuzzy basis function vectors, The approximation error is bounded.

[0076] In one specific implementation, for each subsystem Unknown nonlinear vector functions This invention designs a parallel fuzzy system network for approximation. The first subsystem Each component Approximated by an independent fuzzy system:

[0077]

[0078] To simplify and improve robustness, we introduce a key technical simplification: we do not estimate the full weight vector for each fuzzy system. Instead, it only estimates the square of its norm, i.e. This significantly reduces the number of parameters to be adapted. According to the general approximation theorem for fuzzy systems, there exists an ideal weight vector on a compact set such that the approximation error... Bounded.

[0079] Step 103: Based on the backstepping method, combined with the hyperbolic tangent function and projection operator, recursively design the virtual control law and the actual control law to ensure that the control command is always within the physical saturation limit of the actuator in the active vibration isolation system.

[0080] By introducing the hyperbolic tangent function and using the projection operator to perform bounded correction on the parameter estimates of the fuzzy logic system, the amplitude of each component of the virtual control law and the actual control law has a priori determined upper bound, thereby satisfying the input saturation constraint of the active vibration isolation system.

[0081] In one specific implementation, the controller and Lyapunov function are constructed recursively using a backstepping method.

[0082] Vectorized definition of error coordinates:

[0083]

[0084]

[0085] in, It is obtained by mapping the reference signal through the same barrier function.

[0086] Construction of Lyapunov functions: in the first... Step 1: Select Lyapunov function candidates in the following form:

[0087]

[0088] in, This is the estimation error of the norm squared. The function possesses global positive definiteness and radial unboundedness, and its derivative naturally derives from this. This lays the foundation for bounded control.

[0089] Specifically, by making ( In the form of reverse engineering, virtual control laws are designed. Virtual control law The components are:

[0090] ;

[0091] In the formula, To control the gain, These are adjustable positive design parameters. For error variables, The parameter norm estimate is obtained through the adaptive law with projection. For fuzzy basis function vectors, It includes known coupling terms and the differential term of the reference signal. It is the hyperbolic tangent function.

[0092] Specifically, the actual control law No. The components are:

[0093] ;

[0094] In the formula, For the control gain function, These are adjustable positive design parameters. For the first The error variable of the step, The parameter norm estimate is obtained through the adaptive law with projection. For fuzzy basis function vectors, It is the hyperbolic tangent function.

[0095] In one specific implementation, to ensure that the controller is bounded, the following improved smooth projection operator is used:

[0096]

[0097] in, , These are design parameters.

[0098] Based on the properties of the projection operator and Properties of functions, each component of virtual and actual control laws and All conditions are met:

[0099]

[0100]

[0101] These upper realms and The controller is completely known and computable during the design phase. This is achieved through the appropriate selection of design parameters. and projection boundary This ensures that control commands are always within the physical limits of the actuator.

[0102] This demonstrates that the virtual control law serves as a strategic intermediate command, guiding the system state through a progressive manner within a mathematical "safe space" and providing an adaptive interface for handling unknown dynamics. The actual control law, on the other hand, is a tactical final command, directly driving physical actuators and serving as a pre-proven safety control signal with bounded amplitudes that do not exceed limits. The two are organically combined through backstepping and integrate four core technologies: obstacle function (handling output constraints), tanh function (inherent amplitude limitations), fuzzy adaptation (handling uncertainties), and projection operator (ensuring bounded parameters). This systematically and fundamentally solves the three major control challenges in active vibration isolation of precision equipment: "unknown model, limited output, and input saturation," achieving a balance between safety and performance.

[0103] Step 104: Design a parameter adaptive law to update the parameter estimates of the fuzzy logic system online, and use a projection operator to ensure the boundedness of the parameter estimates during the update process.

[0104] Specifically, the parameter estimates are updated online according to the following formula:

[0105] ;

[0106] In the formula, This is the parameter estimate for the Kth iteration. Sampling time, It is an adaptive function. For projection operators, For adaptive gain.

[0107] In one specific implementation, the Lyapunov function of the entire system is constructed. Differentiate it along the system trajectory and substitute it into all control laws and adaptive laws.

[0108] Using Young's inequality and lemmas in matrix analysis, we handle cross-coupling terms; utilizing key properties of the projection operator, we handle parameter estimation error terms; and utilizing... (or similar inequalities) correlation The derivative of the Lyapunov function. After a series of rigorous scaling operations, it was finally proven that there exist positive constants. , so that:

[0109]

[0110] in, According to the theory of uniform eventual boundedness of nonlinear systems, this inequality proves that: all error signals and parameter estimation error It is uniformly bounded, the system state and controller output It is uniformly bounded, because Boundedness (by (Guaranteed by bounded and barrier function properties), output constraints For all time Established. Tracking error. Ultimately, it will converge to a compact set, the size of which can be adjusted by modifying the design parameters. To shrink arbitrarily.

[0111] The beneficial effects achieved by this application are as follows: Simultaneous processing of dual constraints: For the first time in the vibration isolation control of precision equipment, the two key physical constraints of output constraint and input saturation are handled simultaneously and directly through a unified framework.

[0112] Strong robustness and adaptability: It uses fuzzy logic systems to approximate unknown dynamics and disturbances without requiring a precise mathematical model of the system, and has good robustness to changes in internal parameters and external disturbances.

[0113] The controller is bounded and its upper bound is known: By combining the hyperbolic tangent function and the projection operator, the upper bound of the controller's output amplitude can be predicted during the design phase, providing a clear basis for actuator selection and effectively avoiding performance degradation caused by saturation.

[0114] Balancing performance and safety: While ensuring that the output does not exceed the limits and the input does not saturate, high-precision vibration tracking control is still achieved, taking into account both the transient and steady-state performance of the system.

[0115] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0116] In a specific example, taking a vibration isolation system for precision equipment as an example, the implementation method is introduced:

[0117] 1. System initialization and parameter settings:

[0118] System modeling: Determining the order of the vibration isolation system Identify or estimate the control gain function Clearly define the output displacement Constraint boundary functions and Determine the maximum output force of the actuator. .

[0119] Fuzzy system configuration: For each fuzzy system Define its input variables The universe of discourse is defined, a fuzzy set is defined for each input variable, and a membership function is selected. Based on expert experience or system data, a preliminary fuzzy rule base is established, with a certain number of rules. This determines the dimension and approximation capability of the fuzzy system.

[0120] Controller parameter selection: feedback gain This mainly affects the system's convergence speed and tracking accuracy. A larger value results in faster convergence, but may lead to excessively high control inputs, requiring consideration of other factors. Make a selection. Adaptive gain. and This affects the parameter adaptation speed; a larger value results in faster learning but may cause overshoot and oscillation. Leakage term coefficient. : Used to ensure the boundedness of parameter estimation under no sustained excitation, usually taking a small value. Projection operator parameters: Set upper bounds for the parameters based on prior knowledge of system uncertainties. , and Use very small positive numbers to ensure performance.

[0121] 2. Real-time control loop:

[0122] In each control cycle (by the sampling time of the digital controller) Within the scope of the decision, perform the following steps:

[0123] Signal acquisition: Reading the system output displacement through sensors (and speed) (and other available states).

[0124] Obstacle function calculation: based on current displacement and constraint boundaries , Real-time calculation of obstacle function and related items , .

[0125] Reference signal generation: Calculation of auxiliary reference signal and its derivative .

[0126] Error calculation: Calculate the error variable and (for ).

[0127] Forward computation of fuzzy logic system: for each step Based on the current input vector Calculate the fuzzy basis function vector .

[0128] Control law calculation:

[0129] Starting from the first step, calculate the virtual control law sequentially. Finally, calculate the actual control law. .

[0130] Adaptive law update:

[0131] For each step, calculate the uncorrected adaptive function. Applying the projection operator The parameter estimates are updated using numerical integration methods (such as the Euler method):

[0132]

[0133] in Sampling time.

[0134] Control output: The calculated control force The output is given to the actuator because The design already ensures that the amplitude is bounded, so no additional saturation limiting processing is needed.

[0135] State update: Update the state for the next control cycle (e.g., if some states are unmeasurable, they need to be estimated using a state observer).

[0136] 3. Parameter tuning and optimization:

[0137] In practical applications, online fine-tuning may be necessary: ​​if the tracking error converges slowly, the adjustment can be appropriately increased. If the system has steady-state error or insufficient response to dynamic disturbances, the torque can be appropriately increased. and To accelerate the adaptive speed, if the system oscillates, the speed can be appropriately reduced. , , or increase .

[0138] By constructing a novel vector-based direct barrier function, the physical hard constraints of the system output are equivalently transformed into boundedness requirements of variables in the transformation space. This method is more direct and universal than the traditional barrier Lyapunov function. Secondly, a distributed fuzzy logic system network is used to approximate the unknown nonlinear dynamics encountered in the backstepping design in parallel, and the computational complexity is significantly reduced by adjusting only the square of the norm of the weight vector online. Then, in the recursive design of the backstepping control law, the hyperbolic tangent function and the projection operator are integrated, ensuring that the amplitudes of the virtual control law and the final actual control law have a priori known upper bounds, thus naturally satisfying the input saturation constraint and realizing the "intrinsic saturation" design of the controller. Finally, by constructing a Lyapunov function composed of a logarithmic hyperbolic cosine function and parameter estimation error, and utilizing the key properties of the projection operator, it is rigorously proven that all signals in the closed-loop system are uniformly and ultimately bounded, ensuring that the output constraint is never violated and that tracking performance is excellent.

[0139] like Figure 3 As shown, the following is an embodiment of the control system of the active vibration isolation system for precision equipment provided in this disclosure. It belongs to the same inventive concept as the control method of the active vibration isolation system for precision equipment in the above embodiments. For details not described in detail in the embodiment of the control system of the active vibration isolation system for precision equipment, please refer to the embodiment of the control method of the active vibration isolation system for precision equipment described above.

[0140] The control system of the active vibration isolation system for precision equipment includes:

[0141] The model building unit is used to build a strictly feedback nonlinear model of the active vibration isolation system.

[0142] Function construction unit, used to construct barrier functions so that output constraints are transformed into boundedness requirements of the barrier functions;

[0143] The function approximation unit is used to approximate the unknown nonlinear vector function in the strictly feedback nonlinear model using a fuzzy logic system.

[0144] The control law design unit is used to design bounded virtual and actual control laws by combining the backstepping method, hyperbolic tangent function, and projection operator. This ensures that the control commands are always within the physical saturation limits of the actuators in the active vibration isolation system. Specifically, by introducing the hyperbolic tangent function and combining it with the projection operator to perform bounded correction on the parameter estimates of the fuzzy logic system, the amplitude of each component of the virtual and actual control laws has a priori known upper bound, thereby satisfying the input saturation constraints of the active vibration isolation system.

[0145] The parameter update unit is used to design the parameter adaptive law, update the parameter estimate online, and use the projection operator to ensure the boundedness of the parameter estimate.

[0146] Figure 4 This is a schematic diagram of the hardware structure of an electronic device that implements various embodiments of the present invention.

[0147] The control method for the active vibration isolation system of precision equipment provided in this application embodiment can be applied to electronic devices. Those skilled in the art will understand that the electronic device structure involved in the embodiments of this invention does not constitute a limitation on the electronic device. An electronic device may include more or fewer components than illustrated, or combine certain components, or have different component arrangements. In the embodiments of this invention, the electronic device includes, but is not limited to, laptop computers, desktop computers, workbenches, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the embodiments of this application described and / or claimed herein.

[0148] Electronic devices may include processors, external memory interfaces, internal memory, universal serial bus (USB) interfaces, charging management modules, power management modules, batteries, wireless communication modules, audio modules, speakers, microphones, sensor modules, buttons, cameras, displays, and SIM card interfaces, etc.

[0149] It is understood that the structures illustrated in the embodiments of this application do not constitute a specific limitation on the electronic device. In other embodiments of this application, the electronic device may include more or fewer components than illustrated, or combine some components, or split some components, or have different component arrangements. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

[0150] A processor may include one or more processing units, such as: a central processing unit (CPU), an application processor (AP), a modem processor, a graphics processing unit (GPU), an image signal processor (ISP), a controller, memory, a video codec, a digital signal processor (DSP), a baseband processor, and / or a neural network processing unit (NPU). Different processing units may be independent devices or integrated into one or more processors.

[0151] The processor can serve as the nerve center and command center of an electronic device. The controller can generate operation control signals based on the instruction opcode and timing signals to control the fetching and execution of instructions.

[0152] The processor may also include memory for storing instructions and data. In some embodiments, the memory in the processor is a cache memory. This memory can store instructions or data that the processor has just used or that are used repeatedly. If the processor needs to use the instruction or data again, it can retrieve it directly from this memory. This avoids repeated accesses, reduces processor latency, and thus improves system efficiency.

[0153] An external storage interface (ESI) can be used to connect external memory cards, such as microSD cards, to expand the storage capacity of electronic devices. The external memory card communicates with the processor through the ESI to perform data storage functions, such as saving music and video files on the external memory card.

[0154] Internal memory can be used to store computer executable program code, which includes instructions. The processor executes various functional applications and data processing of electronic devices by running the instructions stored in internal memory. Internal memory can include a program storage area and a data storage area. Internal memory can include high-speed random access memory, and can also include non-volatile memory, such as at least one disk storage device, flash memory device, universal flash storage (UFS), etc.

[0155] Wireless communication functionality in electronic devices can be achieved through antennas, wireless communication modules, modem processors, and baseband processors.

[0156] Wireless communication modules can provide solutions for wireless communication applications in electronic devices, including wireless local area networks (WLANs) (such as wireless fidelity (Wi-Fi) networks), Bluetooth (BT), global navigation satellite system (GNSS), frequency modulation (FM), near field communication (NFC), and infrared (IR) technologies.

[0157] Electronic devices can implement audio functions through audio modules, speakers, receivers, microphones, headphone jacks, and application processors.

[0158] Electronic devices can achieve shooting functions through ISPs, cameras, video codecs, GPUs, displays, and application processors.

[0159] Electronic devices can achieve display functions through GPUs, displays, and application processors.

[0160] A GPU is a microprocessor for image processing, connected to the display screen and application processor. GPUs perform mathematical and geometric calculations for graphics rendering. A processor may include one or more GPUs, which execute program instructions to generate or modify display information.

[0161] A display screen is used to display images, videos, etc. A display screen includes a display panel.

[0162] The storage medium provided in this application stores a program product that enables a control method for implementing an active vibration isolation system for precision equipment.

[0163] The control method for an active vibration isolation system for precision equipment includes: establishing a strict feedback nonlinear model of the active vibration isolation system; constructing a barrier function related to the displacement of the isolation platform in the active vibration isolation system to transform the physical output constraint of the isolation platform displacement into a bounded control objective of the barrier function; using a fuzzy logic system to approximate the unknown nonlinear vector function in the strict feedback nonlinear model; recursively designing virtual and actual control laws based on the backstepping method, combined with the hyperbolic tangent function and the projection operator, to ensure that the control command is always within the physical saturation limit of the actuator in the active vibration isolation system. Specifically, by introducing the hyperbolic tangent function and using the projection operator to perform bounded correction on the parameter estimates of the fuzzy logic system, the amplitude of each component of the virtual and actual control laws has a priori determined upper bound, thereby satisfying the input saturation constraint of the active vibration isolation system; and designing a parameter adaptive law to update the parameter estimates of the fuzzy logic system online, and using the projection operator to ensure the boundedness of the parameter estimates during the update process.

[0164] In some possible implementations, the subject matter of this disclosure, namely the control method and system for an active vibration isolation system for precision equipment, can be implemented as a program product comprising program code that, when the program product is run on a terminal device, causes the terminal device to perform the steps described in the "Exemplary Methods" section of this specification according to various exemplary embodiments of this disclosure.

[0165] The storage medium disclosed herein may be any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples (a non-exhaustive list) of readable storage media include: an electrical connection having one or more wires, a portable disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof.

[0166] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A control method for an active vibration isolation system for precision equipment, characterized in that, include: Establish a rigorous feedback nonlinear model for the active vibration isolation system; Construct a barrier function related to the displacement of the vibration isolation platform in the active vibration isolation system, so as to transform the physical output constraint of the displacement of the vibration isolation platform into the bounded control objective of the barrier function; A fuzzy logic system is used to approximate the unknown nonlinear vector function in the strictly feedback nonlinear model. Based on the backstepping method, and combining the hyperbolic tangent function and the projection operator, virtual control law and actual control law are recursively designed to ensure that the control command is always within the physical saturation limit of the actuator in the active vibration isolation system. In particular, by introducing the hyperbolic tangent function and using the projection operator to perform bounded correction on the parameter estimates of the fuzzy logic system, the amplitude of each component of the virtual control law and the actual control law has a priori determined upper bound, thereby satisfying the input saturation constraint of the active vibration isolation system. The design parameter adaptive law is used to update the parameter estimates of the fuzzy logic system online, and the projection operator is used to ensure the boundedness of the parameter estimates during the update process. The barrier function is as follows: ； In the formula, For the output of the active vibration isolation system, and These are the lower and upper bounds of the output, respectively; Using fuzzy logic systems to approximate unknown nonlinear vector functions Its approximate form is: ； In the formula, For the ideal weight vector, For fuzzy basis function vectors, The approximation error is bounded. Virtual control law The components are: ； In the formula, To control the gain, These are adjustable positive design parameters. For error variables, The parameter norm estimate is obtained through the adaptive law with projection. For fuzzy basis function vectors, It includes known coupling terms and the differential term of the reference signal. It is the hyperbolic tangent function; Actual control law No. The components are: ； In the formula, For the control gain function, These are adjustable positive design parameters. For the first The error variable of the step, The parameter norm estimate is obtained through the adaptive law with projection. For fuzzy basis function vectors, It is the hyperbolic tangent function.

2. The control method for the active vibration isolation system of precision equipment according to claim 1, characterized in that, The strictly feedback nonlinear model is expressed as follows: ； ； ； In the formula, The system state vector is composed of the states of multiple vibration isolation units. To control the input vector, For the output vector, Given a known, non-singular control gain matrix. For an unknown continuous nonlinear vector function, Given a time-varying unknown disturbance vector, the output constraint is defined as follows: ,in, Represents the individual inequalities of vector elements. Let the lower bound constraint vector be... This is the upper bound constraint vector.

3. The control method for the active vibration isolation system of precision equipment according to claim 1, characterized in that, The parameter estimates are updated online according to the following formula: ； In the formula, This is the parameter estimate for the Kth iteration. Sampling time, It is an adaptive function. For projection operators, For adaptive gain.

4. A control system for an active vibration isolation system of precision equipment, applied to the control method of the active vibration isolation system of precision equipment according to any one of claims 1-3, characterized in that, include: The model building unit is used to build a strictly feedback nonlinear model of the active vibration isolation system. Function construction unit, used to construct barrier functions so that output constraints are transformed into boundedness requirements of the barrier functions; The function approximation unit is used to approximate the unknown nonlinear vector function in the strictly feedback nonlinear model using a fuzzy logic system. The control law design unit is used to design bounded virtual and actual control laws by combining the backstepping method, hyperbolic tangent function, and projection operator. This ensures that the control commands are always within the physical saturation limits of the actuators in the active vibration isolation system. Specifically, by introducing the hyperbolic tangent function and combining it with the projection operator to perform bounded correction on the parameter estimates of the fuzzy logic system, the amplitude of each component of the virtual and actual control laws has a priori known upper bound, thereby satisfying the input saturation constraints of the active vibration isolation system. The parameter update unit is used to design the parameter adaptive law, update the parameter estimate online, and use the projection operator to ensure the boundedness of the parameter estimate.

5. An electronic 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, it implements the steps of the control method for the active vibration isolation system of precision equipment as described in any one of claims 1 to 3.

6. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the control method for the active vibration isolation system of precision equipment as described in any one of claims 1 to 3.

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