Multi-modal resonance and disturbance cooperative suppression precision motion control method and system

Abstract

The present application relates to the technical field of precision motion control and vibration suppression, and proposes a precision motion control method and system for multi-modal resonance and disturbance collaborative suppression. Through multi-modal parameter identification and frequency band division, the dominant resonance mode is divided into an instruction excitation frequency band and a disturbance excitation frequency band, and multi-modal input shaper and multi-channel disturbance estimation and feedforward compensation are respectively used for targeted processing. At the same time, through a joint optimization objective function containing a residual vibration index, a disturbance sensitivity index and a phase difference penalty term, the input shaping channel parameters and the feedforward compensator parameters are collaboratively optimized, so that the instruction excitation vibration suppression and the external disturbance compensation are decoupled and matched in the frequency domain. In the multi-modal vibration and multi-source disturbance environment of the precision motion platform, high-precision and high-stability collaborative control is realized.

Description

Technical Field

[0001] This invention relates to the technical field of precision motion control and vibration suppression, specifically to a precision motion control method and system for the coordinated suppression of multimodal resonance and disturbance. Background Technology

[0002] Precision motion platforms are widely used in integrated circuit manufacturing, photolithography, and micro / nano fabrication. These platforms typically feature a rigid-flexible coupling structure to balance large stroke and high stiffness. Simultaneously, their design prioritizes lightweight construction and high responsiveness, enabling them to exhibit multiple low-damped resonant modes. In practical operation, these platforms must not only meet nanometer-level or even sub-nanometer-level positioning accuracy requirements but also maintain high stability under various operating conditions, including high-speed scanning, stepping, and holding. However, these platforms are susceptible to multi-source disturbances, including ground vibration, environmental noise, nonlinear errors in the drive system, and temperature drift. These disturbances superimpose across different frequency bands, resulting in complex, multi-modal vibration responses that severely threaten motion accuracy and system stability.

[0003] Existing commonly used control methods mainly include single-mode input shaping and active disturbance rejection control based on extended state observers (ESOs). Single-mode input shaping only suppresses vibration in a single frequency band of the command excitation, offering limited suppression of multi-mode resonances and lacking real-time compensation for external disturbances. While single-channel ESOs or active disturbance rejection control methods can estimate the total disturbance, they struggle to finely handle multi-frequency disturbances and cannot adequately suppress resonant vibrations from rapidly changing command excitations. Furthermore, existing methods may generate phase conflicts or disturbance accumulation under multi-channel superposition or complex operating conditions, leading to decreased system stability or substandard control performance. They also lack parameter adjustment mechanisms for different motion phases, failing to simultaneously achieve rapid tracking and disturbance suppression during the scanning, stepping, and holding phases. Summary of the Invention

[0004] To address the aforementioned problems, this invention proposes a precision motion control method and system for the coordinated suppression of multimodal resonance and disturbance, achieving high-precision and high-stability coordinated control in the context of multimodal vibration and multi-source disturbance of a precision motion platform.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: One or more embodiments provide a precision motion control method for the coordinated suppression of multimodal resonance and disturbance, comprising the following steps: The frequency and damping ratio of the dominant resonant mode of the controlled precision motion platform are obtained, and the dominant resonant mode is divided into command excitation frequency band and disturbance excitation frequency band. A multi-mode input shaper is designed for the command excitation frequency band to shape the acquired trajectory command into a vibration suppression shaping command; A multi-channel disturbance estimator is constructed for the disturbance excitation frequency band to estimate the disturbance in each frequency band in real time, and the total disturbance compensation command is obtained by the feedforward compensation process of the feedforward compensator. The input shaping channel parameters and feedforward compensator parameters of the multimodal input shaper are optimized by constructing a joint optimization objective function J, which includes residual vibration index, disturbance sensitivity index and phase difference penalty term; The vibration suppression and shaping command, the total disturbance compensation command, and the feedback control command of the controlled precision motion platform are combined into a total control command to drive the movement of the precision motion platform.

[0006] A further technical solution involves obtaining the frequency and damping ratio of the dominant resonant mode of the controlled precision motion platform, and dividing the dominant resonant mode into a command excitation frequency band and a disturbance excitation frequency band, including the following steps: Obtain the frequencies and damping ratios of at least the first two dominant resonant modes of the controlled precision motion platform; Based on the system servo bandwidth and the preset frequency band division coefficient, the resonant frequency of the dominant resonant mode is divided into the command excitation frequency band and the disturbance excitation frequency band.

[0007] A further technical solution includes a multi-mode input shaper comprising multiple second-order all-pass filter units connected in series. Each second-order all-pass filter unit serves as an input shaping channel, corresponding to a dominant resonant mode located within the command excitation frequency band, and is used to perform phase shaping and timing redistribution on the trajectory excitation of the acquired trajectory command near the corresponding resonant frequency.

[0008] A further technical solution involves constructing a multi-channel disturbance estimator for the disturbance excitation frequency band, performing real-time estimation of disturbances in each frequency band, and obtaining a total disturbance compensation command through feedforward compensation. This method includes the following steps: The disturbance response signal after the external disturbance is applied to the disturbance excitation frequency band is obtained, and the disturbance signal is divided into frequencies to obtain the frequency band response signal corresponding to each disturbance excitation mode. Construct a multi-channel disturbance estimator, which includes multiple disturbance estimation channels, each corresponding to a disturbance excitation frequency band. A dominant perturbation frequency is identified within the perturbation estimation channel. Each perturbation estimation channel estimates the perturbation based on the frequency band response signal corresponding to each perturbation excitation mode, thus obtaining the perturbation estimate. ; Based on the disturbance estimation values ​​obtained from the disturbance estimation channels, the corresponding compensation commands for each channel are generated through the feedforward compensator; The compensation commands for each channel are weighted and synthesized to obtain the total disturbance compensation command.

[0009] A further technical solution involves determining the estimator gain Lj of the multi-channel perturbation estimator using the pole placement method, such that the error dynamic matrix A0j of the j-th perturbation estimation channel is... The eigenvalues ​​of LjC0j are located within a preset stable region.

[0010] A further technical solution involves combining the vibration suppression and shaping command, the total disturbance compensation command, and the feedback control command of the controlled precision motion platform into a total control command to drive the precision motion platform's movements. Specifically, the vibration suppression and shaping command is used as the desired motion command of the controlled precision motion platform, and a feedback control command is generated based on the real-time feedback state of the controlled precision motion platform. Simultaneously, the total disturbance compensation command is used as a disturbance feedforward compensation amount and superimposed on the feedback control command to form a total control command for driving the controlled precision motion platform.

[0011] A further technical solution uses the vibration damping and shaping command as the desired input to the feedback controller, and generates a feedback control command based on the trajectory tracking error between the vibration damping and shaping command and the actual feedback state of the controlled precision motion platform.

[0012] One or more embodiments provide a precision motion control system for the coordinated suppression of multimodal resonance and disturbance, including: The resonant mode division module is configured to acquire the frequency and damping ratio of the dominant resonant mode of the controlled precision motion platform, and divide the dominant resonant mode into the command excitation frequency band and the disturbance excitation frequency band. The trajectory command shaping module is configured to shape a multi-modal input shaper designed for the command excitation frequency band to shape the acquired trajectory command into a vibration suppression shaping command. The feedforward compensation generation module is configured to build a multi-channel disturbance estimator for the disturbance excitation frequency band, perform real-time estimation of disturbances in each frequency band, and obtain the total disturbance compensation command through the feedforward compensation process of the feedforward compensator. The input shaping channel parameters and feedforward compensator parameters of the multimodal input shaper are optimized by constructing a joint optimization objective function J, which includes residual vibration index, disturbance sensitivity index and phase difference penalty term; The control module is configured to combine the vibration damping and shaping command, the total disturbance compensation command, and the feedback control command of the controlled precision motion platform into a total control command to drive the precision motion platform to move.

[0013] An electronic device includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor, wherein the computer instructions, when executed by the processor, perform the steps in the aforementioned precision motion control method for coordinated suppression of multimodal resonance and disturbance.

[0014] A computer-readable storage medium for storing computer instructions, which, when executed by a processor, perform the steps in the aforementioned precision motion control method for coordinated suppression of multimodal resonance and disturbance.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention identifies and divides the dominant resonant modes into command excitation frequency bands and disturbance excitation frequency bands through multimodal parameter identification and frequency band segmentation, and performs targeted processing using a multimodal input shaper and multi-channel disturbance estimation and feedforward compensation respectively. At the same time, through a joint optimization objective function including residual vibration index, disturbance sensitivity index and phase difference penalty term, the input shaping channel parameters and feedforward compensator parameters are synergistically optimized, so that command excitation vibration suppression and external disturbance compensation are decoupled and coordinated in the frequency domain. By integrating three technical means (frequency domain division of labor, joint optimization phase constraint, and multi-channel disturbance estimation) into the same control framework, it is possible not only to synergistically suppress multimodal resonance, but also to suppress external disturbances simultaneously, achieving ultra-high precision and high stability motion control effects. Thus, this invention can overcome the problems that single-mode input shaping can only suppress a single command excitation frequency band, single-channel ESO is difficult to finely process multi-frequency disturbances, and simple superposition of multiple channels is prone to phase conflicts. It achieves synergistic suppression of multimodal resonance and external disturbances, improving the trajectory tracking accuracy, disturbance suppression capability, and control stability of precision motion platforms.

[0016] The advantages of the present invention, as well as its additional advantages, will be described in detail in the following specific embodiments. Attached Figure Description

[0017] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute a limitation thereof.

[0018] Figure 1 This is a flowchart of the control method of Embodiment 1 of the present invention; Figure 2 This is an overall structural block diagram of the control system of Embodiment 2 of the present invention; Figure 3 This is a comparative schematic diagram of the traditional single-mode suppression target and the multi-mode suppression target of this embodiment in the comparative experiment of Embodiment 1 of the present invention; Figure 4 This is a comparison curve of residual vibration between a traditional single-mode input shaper and the multi-mode input shaper of the present invention in a comparative experiment of Embodiment 1 of the present invention. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0020] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0021] It should be noted that the terminology used herein is for describing particular embodiments only and is not intended to limit the exemplary embodiments of the present invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof. It should be noted that, without conflict, the various embodiments and features within those embodiments can be combined with each other. The embodiments will now be described in detail with reference to the accompanying drawings.

[0022] Explanation of technical terms: Multimodal resonance refers to the presence of two or more structural resonance peaks at different frequencies in a precision motion platform due to rigid-flexible coupling design.

[0023] Command excitation frequency band: The range of high-frequency resonant frequencies excited by rapid changes in motion commands (such as acceleration and deceleration).

[0024] Disturbance excitation frequency band: The range of low-frequency resonant frequencies excited by external environment (such as ground vibration, airflow disturbance) or internal coupling disturbance.

[0025] Input shaper: A feedforward control technique that eliminates or suppresses residual vibrations of a system at a specific frequency by preprocessing the reference command (such as filtering or convolution).

[0026] All-pass filter: A filter that does not change the amplitude-frequency characteristics of the input signal, but only changes its phase-frequency characteristics. In this invention, it is used to construct a multi-mode input shaper.

[0027] Example 1 In one or more of the technical solutions disclosed in the embodiments, such as Figures 1 to 4 As shown, a precision motion control method for synergistic suppression of multimodal resonance and disturbance includes the following steps: S1: Obtain the frequency and damping ratio of the dominant resonant mode of the controlled precision motion platform, and divide the dominant resonant mode into the command excitation frequency band and the disturbance excitation frequency band; S2: Design a multi-mode input shaper for the command excitation frequency band to shape the acquired trajectory command to obtain the vibration suppression shaping command; S3: Construct a multi-channel disturbance estimator for the disturbance excitation frequency band, estimate the disturbance in each frequency band in real time, and obtain the total disturbance compensation command through the feedforward compensation process of the feedforward compensator. The input shaping channel parameters and feedforward compensator parameters of the multimodal input shaper are optimized by constructing a joint optimization objective function J, which includes residual vibration index, disturbance sensitivity index and phase difference penalty term; S4: Combine the vibration suppression and shaping command, the total disturbance compensation command, and the feedback control command of the controlled precision motion platform into a total control command to drive the movement of the precision motion platform.

[0028] By acquiring the dominant resonant mode frequency and damping ratio of the controlled precision motion platform, and dividing the dominant resonant mode into command excitation frequency band and disturbance excitation frequency band, subsequent control can address different vibration sources separately, avoiding the mixing of command-excited vibration and external disturbance response. By designing a multi-mode input shaper for the command excitation frequency band and shaping the trajectory command to obtain a vibration suppression shaping command, multiple command-excited resonant modes can be synergistically suppressed, reducing residual vibration caused by the trajectory command at the dominant resonant frequency and improving the trajectory tracking stability of the precision motion platform. Furthermore, by constructing a multi-channel disturbance estimator for the disturbance excitation frequency band, disturbances in each frequency band are estimated in real time, and a total disturbance compensation command is generated via a feedforward compensator. This allows for channel-specific estimation and compensation of disturbance components within different disturbance frequency bands, compared to a single total disturbance estimation method. This improves the identification accuracy and compensation targeting of multi-band disturbances. By constructing a joint optimization objective function that includes residual vibration index, disturbance sensitivity index, and phase difference penalty term for the input shaping channel parameters of the multi-mode input shaper and the parameters of the feedforward compensator, it is possible to reduce the phase conflict between the input shaping channel and the disturbance feedforward channel while reducing the residual vibration and disturbance sensitivity caused by the command-induced vibration. This avoids the accumulation of disturbances or the degradation of control performance caused by the simple superposition of multi-channel control quantities. By combining the vibration suppression shaping command, the total disturbance compensation command, and the feedback control command of the controlled precision motion platform into a total control command, the total control command can simultaneously reflect the functions of trajectory tracking, command-induced vibration suppression, and external disturbance compensation. This improves the motion accuracy, vibration suppression effect, and control stability of the precision motion platform under the combined action of multi-mode resonance and external disturbances.

[0029] This embodiment integrates three techniques—frequency domain division of labor, joint optimization of phase constraints, and multi-channel disturbance estimation—into a single control framework. This not only synergistically suppresses multimodal resonances but also simultaneously suppresses external disturbances, achieving ultra-high precision (sub-nanometer / picometer level) and high stability motion control. It avoids phase conflicts between command and disturbance channels and improves multimodal vibration suppression efficiency.

[0030] Step S1 involves multimodal parameter identification and frequency band division of the system; obtaining the frequency and damping ratio of the dominant resonant mode of the controlled precision motion platform, and dividing the dominant resonant mode into command excitation frequency band and disturbance excitation frequency band, including the following steps: Step S11: Obtain the frequencies and damping ratios of at least the first two dominant resonant modes of the controlled precision motion platform; In some embodiments, the frequencies of at least the first two dominant resonant modes of the controlled precision motion platform are obtained through experimental modal analysis or online identification techniques. , , ... and its damping ratio , , ... Subsequently, based on the source of vibration, the dominant resonant frequency was divided into the command excitation frequency band. and disturbance excitation frequency band Experimental modal analysis includes hammer impact testing, frequency sweep excitation testing, or frequency response function analysis; online identification techniques can include frequency response identification based on operational data, recursive least squares identification, subspace identification, or closed-loop frequency response identification, etc. Step S12: Based on the system servo bandwidth and the preset frequency band division coefficient, the resonant frequency of the dominant resonant mode is divided into the command excitation frequency band and the disturbance excitation frequency band. Specifically, frequencies exceeding a preset multiple of the servo bandwidth are assigned to the command excitation band, while the rest are assigned to the disturbance excitation band; the preset multiple is determined by a preset band division coefficient. The division formula is as follows: ; in, The servo bandwidth of the controlled precision motion platform system is known. The preset frequency band division coefficients; This represents the set of dominant resonant frequencies corresponding to the command excitation frequency band; This represents the set of dominant resonant frequencies corresponding to the perturbation excitation frequency band; Configurable frequency band division coefficient The value range is from 0.2 to 0.5.

[0031] S2: Design a multi-mode input shaper for the command excitation frequency band to shape the trajectory command to obtain the vibration suppression shaping command; In some embodiments, the trajectory instruction is a desired motion trajectory instruction generated by the motion planning module based on the target displacement, maximum velocity, maximum acceleration, and maximum jerk constraints. It is used as an instruction signal input to the servo controller and is the target trajectory desired by the control system. Specifically, the multimodal input shaper includes multiple second-order all-pass filter units connected in series; each second-order all-pass filter unit serves as an input shaping channel, corresponding to a frequency band located in the command excitation band. The dominant resonant mode within is used to perform phase shaping and timing redistribution on the trajectory excitation of the acquired trajectory command near the corresponding resonant frequency, thereby reducing the residual vibration of the resonant mode after the motion ends.

[0032] For the i-th element located in the command excitation frequency band The dominant resonant mode within, and its corresponding all-pass filter unit. The transfer function is: ; in, and These are the filter coefficients; achievable, filter coefficients and The residual vibration at the resonant frequency of the mode is minimized. Specifically, the filter system is obtained by minimizing the residual vibration evaluation function, which is used to characterize the residual vibration amplitude or residual vibration energy generated at the corresponding dominant resonant mode after the original trajectory command is processed by the corresponding second-order all-pass filter unit.

[0033] By cascading all the all-pass filter units designed for command-triggered modes, a multimode input shaper is constructed. : ; Its output is a shaping command after vibration suppression preprocessing of the original trajectory command.

[0034] Alternative technical solutions include all-pass filters for multi-mode input shapers. Besides using a second-order IIR structure, higher-order all-pass filters or finite impulse response filters can also be used; the key is to ensure that the amplitude-frequency response is fully pass-through and that the required phase compensation is provided at multiple command excitation frequencies. The design method for all-pass filters is not limited to minimizing residual vibrations; direct phase matching methods can also be employed.

[0035] In step S3, a multi-channel disturbance estimator is constructed for the disturbance excitation frequency band to estimate the disturbance in each frequency band in real time, and the total disturbance compensation command is obtained through feedforward compensation. Specifically, the disturbance response signal is first collected, then the disturbance of each mode is estimated by channel according to the disturbance excitation frequency band, and finally the disturbance estimates of each channel are converted into feedforward compensation commands and synthesized into a total disturbance compensation command.

[0036] In some embodiments, an acceleration sensor is installed on the base of the motion system, the macromotion platform, or other locations susceptible to external disturbances to collect the vibration response signal y(t) characterizing the effect of external disturbances in real time. Based on the disturbance excitation frequency band obtained in step S1... A multi-channel perturbation estimator is constructed, comprising multiple perturbation estimation channels, each corresponding to a perturbation excitation frequency band. A dominant perturbation frequency within; The method for constructing a multi-channel disturbance estimator for the disturbance excitation frequency band in step S3, estimating the disturbance in each frequency band in real time, and obtaining the total disturbance compensation command through feedforward compensation includes the following steps: S31: Obtain the disturbance response signal after the external disturbance action corresponding to the disturbance excitation frequency band, perform frequency division processing on the disturbance signal, and obtain the frequency band response signal corresponding to each disturbance excitation mode; The accelerometer is used to measure the vibration response signal caused by external disturbances, i.e., the disturbance response signal. In this embodiment, the sensor for measuring disturbances, in addition to the accelerometer, can also be replaced by a force sensor, displacement sensor or velocity sensor, depending on the specific application scenario and the type of disturbance that can be measured.

[0037] S32: Construct a multi-channel disturbance estimator, which includes multiple disturbance estimation channels, each corresponding to a disturbance excitation frequency band. A dominant perturbation frequency is identified within the perturbation estimation channel. Each perturbation estimation channel estimates the perturbation based on the frequency band response signal corresponding to each perturbation excitation mode, thus obtaining the perturbation estimate. ; Specifically, a multi-channel perturbation estimator is constructed, which internally contains frequencies corresponding to the perturbation excitation band. For multiple independent estimation channels at various frequencies, the state equation for the j-th estimation channel is: ; in, Let j be the channel state vector estimated for the j-th perturbation. These represent the generalized displacement (or vibration displacement) corresponding to the j-th perturbation excitation mode and the velocity (i.e., the rate of change of displacement) corresponding to the j-th perturbation excitation mode, respectively. This represents the disturbance estimate for the corresponding frequency band; The estimator gain for the j-th perturbation estimation channel; , , These are the state-space parameters determined based on the resonant frequency, damping ratio, and sensor mounting position of the j-th perturbation excitation mode; For the current servo drive input or controller output command, This is the estimated output for the j-th perturbation estimation channel. The disturbance response signal obtained from actual measurement is the vibration response signal collected by the sensor, such as the signal output by the accelerometer. The specific form of the internal state equation of a multimodal perturbation estimator can vary. For example, it can be constructed based on extended state observers of different orders, or it can be a combination of a resonant controller and an observer. Further technical solutions include the estimator gain of the multi-channel perturbation estimator. The error dynamic matrix of the j-th perturbation estimation channel is determined using the pole placement method. The eigenvalues ​​are located within a preset stable region, specifically, the observer bandwidth of the disturbance estimation channel satisfies: ; in, The observer convergence bandwidth for the j-th perturbation estimation channel is given by... Let be the resonant angular frequency of the j-th disturbance excitation mode; through the above settings, the disturbance estimation channel can quickly track the disturbance changes within the corresponding disturbance excitation frequency band.

[0038] S33: The disturbance estimate obtained from the j-th disturbance estimation channel The feedforward compensator generates compensation commands for each channel. ; In some embodiments, the feedforward compensator is constructed based on the inverse model principle: ; in, For the system's nominal model, Let j be the nominal model of the j-th disturbance channel. For low-pass filters, low-pass filters Used to limit the operating frequency band of the feedforward compensator, preventing the feedforward compensator from amplifying high-frequency noise or unmodeled high-order modes.

[0039] : Represents the nominal model of a precision motion platform system, i.e., from the control input To the actual output of the platform The transfer function is an idealized model obtained through system identification or theoretical modeling, used to describe the dynamic characteristics of the platform under undisturbed conditions.

[0040] : indicates the first The nominal model of a disturbance channel, i.e., the external disturbance corresponding to that channel. The disturbance response signal obtained from the sensor measurement The transfer function describes how disturbances in a specific frequency band affect the vibration response of the platform.

[0041] Feedforward compensator design principle: According to the inverse model principle, in order to cancel the disturbance The compensation instruction for the impact on platform output should be: ; In actual implementation, a low-pass filter is introduced. To limit high-frequency gain and avoid amplifying noise or exciting unmodeled modes, the feedforward compensator is written as follows: ; S34: Weight and synthesize the compensation commands from each channel to obtain the total disturbance compensation command. ; ; in, This is the total disturbance compensation command. The compensation command generated for the j-th disturbance estimation channel. Here, m represents the weighting coefficient corresponding to the j-th perturbation estimation channel, and m is the perturbation excitation frequency band. The number of internal disturbance excitation modes.

[0042] In some embodiments, the weighting coefficients are dynamically determined based on the real-time perturbation energy proportion of each perturbation excitation frequency band.

[0043] Specifically, the real-time perturbation energy of the j-th perturbation estimation channel is: ; in, For the j-th disturbance estimation channel, the real-time disturbance energy is... This indicates energy smoothing filtering processing; This is the estimated value of the disturbance; The weighting coefficient for the j-th perturbation estimation channel is: ; in, To prevent positive numbers with a denominator of zero; This enables the total disturbance compensation command to be dynamically allocated according to the real-time disturbance strength of each disturbance excitation frequency band, thereby improving the pertinence and stability of disturbance compensation.

[0044] Further, in step S301, a joint optimization objective function J is established to simultaneously optimize the input shaping channel parameters of the multimodal input shaper and the disturbance feedforward compensator parameters, ensuring that the two channels do not interfere with each other in the frequency domain. The objective function is a joint optimization objective function J that includes residual vibration index, disturbance sensitivity index, and phase difference penalty term: ; Set phase constraint conditions: ; in, For input shaping channels at frequency The residual vibration amplitude at that location, For the feedforward channel at frequency Perturbation sensitivity at the location. and The two channels are respectively at the frequency Phase response at; , , This is a weighting coefficient, which can be adjusted according to specific project requirements. The general principle is: if the system has high requirements for instruction tracing, increase the weighting coefficient. If the system requires high anti-interference capabilities, then increase... ; To ensure phase decoupling, a smaller value is usually chosen.

[0045] The optimization constraints are: , Dominant resonant frequency. It can be less than 15°; Optionally, optimization algorithms such as Sequential Quadratic Programming (SQP), genetic algorithms, and particle swarm optimization can be used to solve the problem, ensuring that the two channels satisfy phase constraints at the resonant frequency, thus achieving frequency domain decoupling and synergistic effects. The optimization variables are the input shaping channel parameters (filter coefficients in S2) and the disturbance feedforward compensator parameters (feedforward gain and low-pass filter parameters in S3); the output result is the globally optimal solution, ensuring that the two channels do not interfere with each other and achieve synergistic effects at the resonant frequency.

[0046] S301's offline optimization is performed separately for different motion stages, resulting in multiple parameter sets (e.g., scan stage parameter set, stepping stage parameter set, hold stage parameter set), each set representing the optimal solution for that stage. S302, on the other hand, runs online and directly calls the corresponding parameter set based on the current motion stage, without recalculating or adjusting parameters online. Therefore, the two are not contradictory; they represent a process of first optimizing offline in stages, then switching between them online.

[0047] Furthermore, to improve the overall performance at different motion stages, this method also includes joint optimization and online scheduling of the input shaper parameters and feedforward compensator parameters: S301: Offline joint optimization, for different motion stages such as scanning, stepping, and holding, solves for the corresponding optimal input shaper parameters and feedforward compensator parameters respectively, and obtains multiple sets of optimal parameter sets.

[0048] S302: During online operation, the current stage is identified based on the real-time motion status (speed, acceleration, etc.), and the optimal parameter group for the corresponding stage in S301 is called to realize the scheduling and switching of control parameters.

[0049] A further technical solution involves the following online scheduling and switching process for S302: Scanning phase: When the system speed is greater than the first speed threshold and the absolute value of acceleration is less than the first acceleration threshold, the notch width of the input shaper is set to be greater than 0.3 times the system servo bandwidth, and the bandwidth of the disturbance feedforward compensator is set to be less than 0.1 times the system servo bandwidth; Stepping phase: When the system speed is less than or equal to the first speed threshold and greater than zero, or the absolute value of acceleration is greater than or equal to the first acceleration threshold, the notch width of the input shaper is set to be less than or equal to 0.3 times and greater than 0.05 times the system servo bandwidth, and the bandwidth of the disturbance feedforward compensator is set to be greater than or equal to 0.1 times and less than 0.3 times the system servo bandwidth. Hold Phase: When the system speed is zero and the duration is greater than the first time threshold, the input shaper is disabled and the feedforward compensator bandwidth is reduced to less than 0.05 times the system servo bandwidth, for example, below 50Hz, but the specific value can be calibrated according to the actual system. The system is configurable, with a first velocity threshold of 0.5 m / s, a first acceleration threshold of 1 m / s², a first time threshold of 100 ms, and a preset low frequency value of 50 Hz. The motion phase division thresholds are set based on a typical ultra-precision motion platform. For different application scenarios, these thresholds can be recalibrated and adjusted according to the actual system's dynamic characteristics and accuracy requirements.

[0050] Specifically, during the scanning phase: when the system speed v>0.5m / s and the acceleration |a|<1m / s², a notch width greater than 0.3 times the system servo bandwidth and a disturbance feedforward bandwidth less than 0.1 times the system servo bandwidth are used to prioritize ensuring the smoothness of trajectory tracking; Stepping phase: System speed 0 <v ≤ 0.5m s 或加速度 |a| ≥ 1m s² 时，采用大于0.05倍且小于等于0.3倍系统伺服带宽的陷波宽度和大于等于0.1倍且小于0.3倍系统伺服带宽的扰动前馈带宽，平衡快速性与稳定性； 保持阶段：系统速度 v="0" 且持续时间 t>At 100ms, the input shaper is disabled, and the disturbance feedforward bandwidth is reduced to less than 0.05 times the system servo bandwidth (e.g., 50Hz) to fully suppress external disturbances and achieve ultra-precise positioning.

[0051] S4 combines the vibration damping and shaping command, the total disturbance compensation command, and the feedback control command of the controlled precision motion platform into a total control command to drive the movement of the precision motion platform. Specifically, the vibration suppression and shaping command obtained in step S2 is used as the desired motion command of the controlled precision motion platform, and a feedback control command is generated based on the real-time feedback state of the controlled precision motion platform. At the same time, the total disturbance compensation command obtained in step S3 is used as the disturbance feedforward compensation amount and superimposed on the feedback control command to form a total control command for driving the controlled precision motion platform.

[0052] In this process, the vibration damping and shaping command is used as the desired input of the feedback controller. Based on the trajectory tracking error between the vibration damping and shaping command and the actual feedback state of the controlled precision motion platform, the feedback controller (such as PID) generates a feedback control command. This command, together with the vibration damping and shaping command and the total disturbance compensation command, forms the total control command.

[0053] Simultaneously, a trajectory feedforward command is generated based on the vibration suppression and shaping command, and the trajectory feedforward command, feedback control command, and total disturbance compensation command are superimposed to obtain a total control command to drive the precision motion platform to move.

[0054] To illustrate the effectiveness of the method in this embodiment, a comparative experiment was conducted, which is described below; Figure 3 This is a comparative diagram of traditional single-mode suppression targets and the multi-mode suppression targets established in this invention. The horizontal axis represents frequency, and the vertical axis represents amplitude. Figure 3 The data shows multiple resonance peaks (50Hz, 85Hz, 120Hz) in the system. Traditional single-mode shaping only forms a suppression valley at a single frequency, while the multi-mode shaping designed in this embodiment forms deep suppression valleys at multiple resonance frequencies, achieving comprehensive suppression of broadband vibrations.

[0055] Figure 4 This is a comparison curve of residual vibration between a traditional single-mode input shaper and the multi-mode robust input shaper of this invention. The horizontal axis represents frequency, covering... , Nearby frequency bands; the vertical axis represents the residual vibration amplitude. It can be seen that single-mode shaping only occurs in... The vibration is lower at that location. Significant vibrations still exist at this location; while the multimodal shaping in this embodiment... , It maintains a low vibration level near multiple frequencies, and the vibration amplitude is below the set threshold throughout the entire frequency band.

[0056] Example 2 Based on Example 1, this example provides a precision motion control system for coordinated suppression of multimodal resonance and disturbance, including: The resonant mode division module is configured to acquire the frequency and damping ratio of the dominant resonant mode of the controlled precision motion platform, and divide the dominant resonant mode into the command excitation frequency band and the disturbance excitation frequency band. The trajectory command shaping module is configured to shape a multi-modal input shaper designed for the command excitation frequency band to shape the acquired trajectory command into a vibration suppression shaping command. The feedforward compensation generation module is configured to build a multi-channel disturbance estimator for the disturbance excitation frequency band, perform real-time estimation of disturbances in each frequency band, and obtain the total disturbance compensation command through the feedforward compensation process of the feedforward compensator. The input shaping channel parameters and feedforward compensator parameters of the multimodal input shaper are optimized by constructing a joint optimization objective function J, which includes residual vibration index, disturbance sensitivity index and phase difference penalty term; The control module is configured to combine the vibration damping and shaping command, the total disturbance compensation command, and the feedback control command of the controlled precision motion platform into a total control command to drive the precision motion platform to move.

[0057] Specifically, the system workflow in this embodiment is as follows: The desired trajectory command is first fed into the multimodal input shaper. The internal structure of this multimodal input shaper consists of multiple all-pass filters connected in series, and its parameters are set by the joint optimization module based on the system identification results and motion phase information. Its core function is to preprocess the command and suppress high-frequency resonances excited by rapid command changes.

[0058] Meanwhile, vibration sensors mounted on the system base collect external disturbance signals in real time and send them to a multi-channel disturbance estimator. The multi-channel disturbance estimator contains multiple parallel estimation channels, each corresponding to a specific low-frequency disturbance band, capable of accurately estimating the disturbance dynamics of each band. The disturbance estimates from each channel are processed by a feedforward compensator to generate corresponding compensation signals, which are then weighted and fused in a weighted summation module based on the real-time energy proportion of each band to form the total disturbance compensation signal.

[0059] The shaping command output by the multimodal input shaper is added to the total disturbance compensation signal output by the weighted summation module in the first summation unit to form the total feedforward control quantity.

[0060] The actual output of the system is compared with the expected vibration damping and shaping command to generate a tracking error. This error is sent to the feedback controller to generate a feedback control quantity.

[0061] The total feedforward control quantity and the feedback control quantity are added together in the second summing unit to generate the final drive signal, which is applied to the precision motion platform.

[0062] During this process, the joint optimization module continuously monitors the system status and dynamically adjusts key parameters in the multimodal input shaper, feedforward compensator, and weighted summation module, such as notch width, observer bandwidth, and weighting coefficients, according to different motion stages such as scanning, stepping, and holding, to achieve adaptive switching of the control system.

[0063] Through the aforementioned frequency domain division of labor, joint optimization, and motion adaptive mechanism, this invention achieves synergistic suppression of command-induced resonance and external disturbance vibration, significantly improving the positioning stability and trajectory tracking accuracy of the ultra-precision optomechanical system under complex working conditions.

[0064] It should be noted that each module in this embodiment corresponds one-to-one with each step in embodiment 1, and their specific implementation process is the same, so it will not be repeated here.

[0065] Example 3 Based on Embodiment 1, this embodiment provides an electronic device, including a memory and a processor, as well as computer instructions stored in the memory and running on the processor. When the computer instructions are executed by the processor, they complete the steps in the precision motion control method for coordinated suppression of multimodal resonance and disturbance described in Embodiment 1.

[0066] Example 4 Based on Embodiment 1, this embodiment provides a computer-readable storage medium for storing computer instructions. When the computer instructions are executed by a processor, they complete the steps in the precision motion control method for coordinated suppression of multimodal resonance and disturbance described in Embodiment 1.

[0067] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0068] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.< / v>

Claims

1. A precision motion control method for coordinated suppression of multimodal resonance and disturbance, characterized in that, Includes the following steps: The frequency and damping ratio of the dominant resonant mode of the controlled precision motion platform are obtained, and the dominant resonant mode is divided into command excitation frequency band and disturbance excitation frequency band. A multi-mode input shaper is designed for the command excitation frequency band to shape the acquired trajectory command into a vibration suppression shaping command; A multi-channel disturbance estimator is constructed for the disturbance excitation frequency band to estimate the disturbance in each frequency band in real time, and the total disturbance compensation command is obtained by the feedforward compensation process of the feedforward compensator. The input shaping channel parameters and feedforward compensator parameters of the multimodal input shaper are optimized by constructing a joint optimization objective function J, which includes residual vibration index, disturbance sensitivity index and phase difference penalty term; The vibration suppression and shaping command, the total disturbance compensation command, and the feedback control command of the controlled precision motion platform are combined into a total control command to drive the movement of the precision motion platform.

2. The precision motion control method for coordinated suppression of multimodal resonance and disturbance as described in claim 1, characterized in that, The process of obtaining the frequency and damping ratio of the dominant resonant mode of the controlled precision motion platform, and dividing the dominant resonant mode into command excitation frequency band and disturbance excitation frequency band, includes the following steps: Obtain the frequencies and damping ratios of at least the first two dominant resonant modes of the controlled precision motion platform; Based on the system servo bandwidth and the preset frequency band division coefficient, the resonant frequency of the dominant resonant mode is divided into the command excitation frequency band and the disturbance excitation frequency band.

3. The precision motion control method for coordinated suppression of multimodal resonance and disturbance as described in claim 1, characterized in that, The multimodal input shaper includes multiple second-order all-pass filter units connected in series. Each second-order all-pass filter unit serves as an input shaping channel, corresponding to a dominant resonant mode located within the command excitation frequency band, and is used to perform phase shaping and timing redistribution on the trajectory excitation of the acquired trajectory command near the corresponding resonant frequency.

4. The precision motion control method for coordinated suppression of multimodal resonance and disturbance as described in claim 1, characterized in that, A method for constructing a multi-channel disturbance estimator for the disturbance excitation frequency band, estimating disturbances in each frequency band in real time, and obtaining the total disturbance compensation command through feedforward compensation includes the following steps: The disturbance response signal after the external disturbance is applied to the disturbance excitation frequency band is obtained, and the disturbance signal is divided into frequencies to obtain the frequency band response signal corresponding to each disturbance excitation mode. Construct a multi-channel disturbance estimator, which includes multiple disturbance estimation channels, each corresponding to a disturbance excitation frequency band. A dominant perturbation frequency is identified within the perturbation estimation channel. Each perturbation estimation channel estimates the perturbation based on the frequency band response signal corresponding to each perturbation excitation mode, thus obtaining the perturbation estimate. ; Based on the disturbance estimation values ​​obtained from the disturbance estimation channels, the corresponding compensation commands for each channel are generated through the feedforward compensator; The compensation commands for each channel are weighted and synthesized to obtain the total disturbance compensation command.

5. The precision motion control method for coordinated suppression of multimodal resonance and disturbance as described in claim 1, characterized in that, The estimator gain Lj of the multi-channel disturbance estimator is determined by the pole placement method, so that the eigenvalues ​​of the error dynamic matrix of the j-th disturbance estimation channel are located within a preset stable region.

6. The precision motion control method for coordinated suppression of multimodal resonance and disturbance as described in claim 1, characterized in that, The vibration suppression and shaping command, the total disturbance compensation command, and the feedback control command of the controlled precision motion platform are combined into a total control command to drive the precision motion platform's actions. Specifically, the vibration suppression and shaping command is used as the desired motion command of the controlled precision motion platform, and a feedback control command is generated based on the real-time feedback state of the controlled precision motion platform. At the same time, the total disturbance compensation command is used as the disturbance feedforward compensation amount and superimposed on the feedback control command to form a total control command for driving the controlled precision motion platform.

7. The precision motion control method for coordinated suppression of multimodal resonance and disturbance as described in claim 1, characterized in that, The vibration damping and shaping command is used as the desired input to the feedback controller, and the feedback control command is generated based on the trajectory tracking error between the vibration damping and shaping command and the actual feedback state of the controlled precision motion platform.

8. A precision motion control system for coordinated suppression of multimodal resonance and disturbance, characterized in that, include: The resonant mode division module is configured to acquire the frequency and damping ratio of the dominant resonant mode of the controlled precision motion platform, and divide the dominant resonant mode into the command excitation frequency band and the disturbance excitation frequency band. The trajectory command shaping module is configured to shape a multi-modal input shaper designed for the command excitation frequency band to shape the acquired trajectory command into a vibration suppression shaping command. The feedforward compensation generation module is configured to build a multi-channel disturbance estimator for the disturbance excitation frequency band, perform real-time estimation of disturbances in each frequency band, and obtain the total disturbance compensation command through the feedforward compensation process of the feedforward compensator. The input shaping channel parameters and feedforward compensator parameters of the multimodal input shaper are optimized by constructing a joint optimization objective function J, which includes residual vibration index, disturbance sensitivity index and phase difference penalty term; The control module is configured to combine the vibration damping and shaping command, the total disturbance compensation command, and the feedback control command of the controlled precision motion platform into a total control command to drive the precision motion platform to move.

9. An electronic device, characterized in that, It includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor, which, when executed by the processor, perform the steps in the precision motion control method for coordinated suppression of multimodal resonance and disturbance as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, Used to store computer instructions, which, when executed by a processor, complete the steps in the precision motion control method for coordinated suppression of multimodal resonance and disturbance as described in any one of claims 1-7.

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