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1
Oliinyk, O. Yu. "VIBRATION FREQUENCY DENSITY CONTROL METHOD IN VIBRATION CONDITIONS." METHODS AND DEVICES OF QUALITY CONTROL, no. 2(43) (December 24, 2019): 41–47. http://dx.doi.org/10.31471/1993-9981-2019-2(43)-41-47.
Повний текст джерелаАнотація:
The use of existing vibration frequency measuring instruments for monitoring technological parameters inside apparatus and equipment is limited due to the presence of vibrations and industrial noise. The lack of data on the use of part of the technological apparatus as flow resonators through the unexplored basic analytical equations for determining the amplitude-frequency characteristics of such resonators determined the direction of these studies. The article is devoted to studies aimed at establishing the relationship between the vibrational field of the resonator, which is used as part of the technological apparatus with a controlled environment, and its reaction in the form of a change in the frequency or amplitude of the resonator’s own vibrations, which carries information about the properties of the substance in the apparatus. The experimental setup diagram, experimental methodology, and data on determining the oscillation frequency of the resonator under vibration conditions for metallic (corrosion-resistant steel) and non-metallic (organic glass) resonators are presented. The curves obtained from the experimental values were approximated using linear and hyperbolic approximations. It was found that the use of hyperbolic approximation reduces the average approximation error by more than six times. It was found that the error of the hyperbolic approximation error does not exceed 0.022% for a metal resonator and 0.05% for an organic glass resonator. The conducted experimental studies confirm the presence of a determinate coupling of the measured frequency characteristics of the resonator with the density, which was measured inside the equipment. The obtained data was used to develop the scientific and methodological foundations of the vibrational frequency control method in conditions of vibration using a part of the device as a resonator of the vibrational frequency sensor.
2
Barrault, Guillaume, Dunant Halim, and Colin Hansen. "High frequency spatial vibration control using method." Mechanical Systems and Signal Processing 21, no. 4 (May 2007): 1541–60. http://dx.doi.org/10.1016/j.ymssp.2006.08.013.
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3
Jiao, Z., P. Chen, Q. Hua, and S. Wang. "Adaptive vibration active control of fluid pressure pulsations." Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering 217, no. 4 (June 1, 2003): 311–18. http://dx.doi.org/10.1177/095965180321700407.
Повний текст джерелаАнотація:
Conventionally, passive hydraulic absorbers are utilized in order to reduce the vibrations of the fluid power supply systems. It is very difficult to adapt the variable operation conditions, such as inconsistent vibration frequency and varying loads. This paper presents a new vibration active control method to diminish the vibrations of the fluid power supply efficiently. This method is adaptive and robust in controlling the fluctuating frequencies and load disturbances and is capable of keeping the vibrations at a minimum level under variable pump speeds. This paper illustrates the theory and experimentation of vibration active control of a fluid power supply pipeline system in detail. The multilayer piezoelectric technology (PZT) driven orifice valve is designed with characteristics of a proportional opening area to the control voltage, a high-frequency bandwidth and small size. The adaptive-optimum control method is adopted to adjust the control parameters at any instant against emerging disturbances. Based on the test rig, different vibration control methods were applied; the results indicate and confirm the validity of this principle.
4
Cheng, Mingke, Feng Gao, and Yan Li. "Vibration Detection and Experiment of PMSM High Speed Grinding Motorized Spindle Based on Frequency Domain Technology." Measurement Science Review 19, no. 3 (June 1, 2019): 109–25. http://dx.doi.org/10.2478/msr-2019-0017.
Повний текст джерелаАнотація:
Abstract The spindle vibrations of the high-speed grinding motorized spindle largely determine the machining quality and precision. In order to accurately predict the spindle vibrations of the PMSM high-speed grinding motorized spindle, the vibration causes are explored and analyzed. The radial vibration, inclined vibration, and axial vibration model are established. The experimental modal analysis method is proposed to analyze the dynamic response of the spindle and to identify the modal parameters of the spindle structure. Thereafter, the frequency response function (FRF) is calculated by self-power spectrum and cross-power spectrum. It is transformed into the vibration spectrum analysis of the spindle. The least-square method is used to fit the radial trajectory of the spindle. This paper aims to propose double standard spheres for 5- DOF spindle vibrations used to detect the spindle vibrations. In the experiment, the method proposed in this paper can effectively and accurately determine the causes of the spindle vibrations. The spectrum analysis and the trajectory are common tools in the spindle vibration detection.
5
Du, Xiangyu, Rong Huang, Balaji Vengatachalam, and Zishun Liu. "Vibration control for slotted plate using structural intensity method." International Journal of Computational Materials Science and Engineering 07, no. 01n02 (June 2018): 1850006. http://dx.doi.org/10.1142/s2047684118500069.
Повний текст джерелаАнотація:
In this paper, we study the vibration performance of simply supported slotted plate using structural intensity (SI) method. First, the SI distribution of the slotted plate under given excitation for different slot depths is obtained using finite element methods. The SI streamline of each case shows that the SI distribution can be significantly affected by adjusting the slot depth. The optimal position of dampers which can effectively implement vibration control of slotted plate for the fixed value of exciting frequency can be obtained from the SI streamline distribution. In case of changing vibrating frequencies, a new strategy of vibration control by adding soft material (hydrogel) layers is proposed. The main advantage of this strategy is that the properties of hydrogel can be easily adjusted by changing the chemical potential, thereby achieving the desired vibration control for different excitation conditions. The effectiveness of the proposed vibration control using hydrogel layers is investigated using SI method. The SI distribution and SI streamlines of the slotted plate with the new vibration control show that the proposed strategy is convenient. Our proposed method conceptualizes a new approach toward vibration control using constrained hydrogel layer.
6
Zheng, Yangbo, Ni Mo, Zhe Sun, Yan Zhou, and Zhengang Shi. "Study on Unbalanced Magnetic Pulling Analysis and Its Control Method for Primary Helium Circulator of High-Temperature Gas-Cooled Reactor." Energies 12, no. 19 (September 26, 2019): 3682. http://dx.doi.org/10.3390/en12193682.
Повний текст джерелаАнотація:
In addition to providing an extremely clean environment for primary loop of high-temperature gas-cooled reactor (HTR), the primary helium circulator (PHC) using electromagnetic levitation technology also provides an effective means for vibration control. Besides synchronous vibration produced by mass imbalance and sensor runout, double-frequency vibration produced by unbalanced magnetic pull (UMP) is serious in PHC engineering prototype (PHC-EP). In this paper, we firstly analyzed the mechanism of UMP and the multi-frequency vibration characteristics in combination with the PHC-EP. Then we put forward a distributed iterative learning control (ILC) algorithm and a parallel control scheme to suppress the periodic vibrations. Finally, we verified the methods by carrying out experimental researches on the active magnetic bearing (AMB) bench of PHC-EP. The results show that the methods put forward in this paper have significant control effect on the double-frequency vibration generated by UMP of the PHC-EP and provide theoretical and practical references for the PHC safe operation in HTR.
7
Ma, Xibin, Zhangwei Chen, Huinong He, and Yugang Zhao. "Research on Control Technologies for a High-Precision Multi-Source Vibration Simulation System." Energies 11, no. 11 (October 29, 2018): 2956. http://dx.doi.org/10.3390/en11112956.
Повний текст джерелаАнотація:
Vehicles commonly suffer from the narrow-band noises and vibrations, usually a superposition of multiple sinusoidal signals, due to the excitations of engines, electrical motors, gear boxes, and other rotating mechanical parts. These excitations are transmitted to a reference point of some structure with certain transmission paths. The vibration signal measured at the reference point can be used for power system monitoring, fault diagnosis, modal analysis, noise analysis, etc. For convenience, researchers in a laboratory usually use shakers to generate expected narrow-band vibration signals acting on the vehicle structure reference points to simulate the vibration signals. However, there is a prominent difficulty in ensuring the amplitude and phase accuracy of each sub-frequency component simultaneously. In order to improve the accuracy of generating the expected vibration signal, this paper presents a multi-source vibration simulation control technology based on the tracking filter method. The main idea is to use the tracking filter to estimate the amplitude and phase of the target sub-frequency component accurately. Further, on the target sub-frequency, the drive signal of shakers is then corrected based on the amplitude and phase errors to achieve a more accurate target vibration signal. The amplitude and phase of each sub-frequency component in the excitation signal can be controlled independently. Compared with other Fast Fourier Transform (FFT)-based frequency domain analysis algorithms and numerical methods by solving the equations, the tracking filter method has a higher frequency resolution and higher accuracy. It can be easily realized in real time applications due to its simplicity. Finally, verification experiments are completed. The experimental results show that the multi-source vibration simulation control technology presented in this paper can achieve high-precision amplitude and phase on each sub-frequency component of the target vibration signals, which contain up to eight sub-frequency components.
8
Shiota, Ryosuke, Tatsuya Furuki, Toshiki Hirogaki, and Eiichi Aoyama. "Investigation of Control Methods of Chatter Vibration Based on Analysis of End-Milling Chatter Mark." Advanced Materials Research 1136 (January 2016): 639–44. http://dx.doi.org/10.4028/www.scientific.net/amr.1136.639.
Повний текст джерелаАнотація:
Chatter vibration generated by coupling a work-piece, machine tools, and cutting tool is a serious problem for engineers. A regular pattern forms the machined surface when chatter vibration occurs. There must be a direct relationship between the relative displacement and machined surface. We propose a method for controlling chatter vibration of end-milling from a machined surface. Hammering tests were first carried out to determine the natural frequencies of machine tools and the tool system, which are likely to be the cause of vibration. We also propose a technique of applying reverse analysis to end-milling surfaces. The machined surface is assumed to include an essential index to easily control chatter vibration at the factory. We found that chatter vibration occurs near the frequency of the cutting tool, tool holder, and their coupling, not at the natural frequency, and the chatter vibration frequency can be calculated by analyzing the surface pattern and cutting conditions. Moreover, the proposed method was effective in analyzing chatter vibrations including more than two kinds of natural frequencies at the same time.
9
Zhang, Laixi, Chenming Zhao, Feng Qian, Jaspreet Singh Dhupia, and Mingliang Wu. "A Variable Parameter Ambient Vibration Control Method Based on Quasi-Zero Stiffness in Robotic Drilling Systems." Machines 9, no. 3 (March 21, 2021): 67. http://dx.doi.org/10.3390/machines9030067.
Повний текст джерелаАнотація:
Vibrations in the aircraft assembly building will affect the precision of the robotic drilling system. A variable stiffness and damping semiactive vibration control mechanism with quasi-zero stiffness characteristics is developed. The quasi-zero stiffness of the mechanism is realized by the parallel connection of four vertically arranged bearing springs and two symmetrical horizontally arranged negative stiffness elements. Firstly, the quasi-zero stiffness parameters of the mechanism at the static equilibrium position are obtained through analysis. Secondly, the harmonic balance method is used to deal with the differential equations of motion. The effects of every parameter on the displacement transmissibility are analyzed, and the variable parameter control strategies are proposed. Finally, the system responses of the passive and semiactive vibration isolation mechanisms to the segmental variable frequency excitations are compared through virtual prototype experiments. The results show that the frequency range of vibration isolation is widened, and the stability of the vibration control system is effectively improved without resonance through the semiactive vibration control method. It is of innovative significance for ambient vibration control in robotic drilling systems.
10
Zhou, Chun. "Control Lorenz System with Vibration Estimation with Averaging Method." Applied Mechanics and Materials 43 (December 2010): 36–39. http://dx.doi.org/10.4028/www.scientific.net/amm.43.36.
Повний текст джерелаАнотація:
The vibrational control theory stems from the well-known of stabilization of the upper unstable equilibrium position of the inverted pendulum having suspension point vibration along the vertical line with amplitude as small as desired and a frequency reason high. Chaotic phenomena have been found in many nonlinear systems including continuous time and discrete time. The chaotic systems are characterized by their extreme sensitivity to initial conditions, nonperiodic and boundary. The trajectories start even from close initial states will diverge from each other at an exponential rate as time goes. The vibrational control method was applied to Lorenz system. The effect of the control can be estimated with the APAZ method. It was showed that vibrational control brought the controlled Lorenz system to stable equilibrium with appropriate parameters. Numerical simulation demonstrated validity of the proposed method.
11
Nagai, Nobuyuki, Seiji Hashimoto, Yoshimitsu Fujikura, Jyunpei Takahashi, Shunji Kumagai, Makoto Kasai, Kenji Suto, and Hiroaki Okada. "Reproduction of Vehicle Vibration by Acceleration-Based Multi-Axis Control." Applied Mechanics and Materials 251 (December 2012): 129–33. http://dx.doi.org/10.4028/www.scientific.net/amm.251.129.
Повний текст джерелаАнотація:
This paper presents the development of the 3-axis vibrating machine precisely reproducing vehicle's acceleration characterized with multi-mode vibration. For the reproduction in vertical axis, at first, the system identification experiment of the vibrator is carried out. Using the identified model, the feedforward control based on the pole-zero cancellation method is applied to realize the ideal transfer gain of one from the acceleration reference to its output. Next, for reproducing the acceleration in horizontal plane, the continuous-path tracking (CPT) control system is constructed using the precision XY stage. In the CPT control system, the disturbance observer is introduced focusing on the accurate reproduction within limited frequency. Finally, the experimental verification of the proposed 3-axis acceleration vibration reproduction system is shown using the developed DSP-controlled 3-axis vibrating machine.
12
Yang, B., and C. D. Mote. "Frequency-Domain Vibration Control of Distributed Gyroscopic Systems." Journal of Dynamic Systems, Measurement, and Control 113, no. 1 (March 1, 1991): 18–25. http://dx.doi.org/10.1115/1.2896350.
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A new method is presented for vibration control of distributed gyroscopic systems. The control is formulated in the Laplace transform domain. The transfer function of a closed-loop system, consisting of the plant, a feedback control law and the dynamics of the sensing and actuation devices, is derived. Stability analyses of the closed-loop system use both the root locus method and the generalized Nyquist criterion. Two stability criteria are obtained. Design of stabilizing controllers is carried out for both colocation and noncolocation of the sensor and actuator. The effects of time-delay and noncolocation of the sensor and actuator on the system stability are analyzed. In addition, the relationship between the root locus method and the generalized Nyquist criterion is discussed.
13
Cole, M. O. T., P. S. Keogh, and C. R. Burrows. "Control of multifrequency rotor vibration components." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 216, no. 2 (February 1, 2002): 165–77. http://dx.doi.org/10.1243/0954406021525106.
Повний текст джерелаАнотація:
A method is developed for the control of rotor lateral vibration using multiple frequency components. The control strategy uses a generalized algorithm for the real-time calculation of the amplitude and phase of the vibration components. The complex amplitudes are evaluated successively at the controller sample frequency and can therefore be used for dynamic feedback control. Parallel control of all frequency components is achieved using frequency-matched control signals with amplitude and phase dictated by the control algorithm. The strategy is evaluated experimentally using a flexible rotor system with magnetic bearings. The controller gain matrices are calculated from frequency response identification. The controller sample frequency is the rotational frequency, but the vibration frequencies that are controlled simultaneously include harmonics and subharmonics of the rotational frequency. The controller is shown to be effective in reducing rotor vibration arising from various sources and having a number of discrete frequency components.
14
Gong, Qingmei, Canchang Liu, Yingzi Xu, Chicheng Ma, Jilei Zhou, Ruirui Jiang, and Changcheng Zhou. "Nonlinear vibration control with nanocapacitive sensor for electrostatically actuated nanobeam." Journal of Low Frequency Noise, Vibration and Active Control 37, no. 2 (August 21, 2017): 235–52. http://dx.doi.org/10.1177/1461348417725953.
Повний текст джерелаАнотація:
The model of a clamped–clamped Euler–Bernoulli beam is presented in order to study nonlinear vibration control of electrostatically actuated nanobeam with nanocapacitive sensor, considering primary and superharmonic resonances. The capacitance of nanobeam capacitor changes with the nanobeam deformation. The nanocapacitive sensor is applied to extract vibration signals and to transform enlarged signals into controller to control nanobeam vibrations. The method of multiple scales is used to obtain the first-order approximate solutions and derive the amplitude–frequency equation. The nonlinear vibration characteristics and amplitude–frequency response of nanobeam vibration system are studied under different excitation voltage, feedback gains, and damping. The relationships between amplitude and system parameters are discussed in detail. The presented analytical and numerical simulations show that dynamic response of nanobeam is stable when the appropriate parameters are chosen. This investigation provides a better understanding of the nonlinear vibration of nanoelectromechanical systems devices based on nanobeam.
15
Song, Chunsheng, Yao Xiao, Chuanchao Yu, Wei Xu, and Jinguang Zhang. "H∞ active control of frequency-varying disturbances in a main engine on the floating raft vibration isolation system." Journal of Low Frequency Noise, Vibration and Active Control 37, no. 2 (August 21, 2017): 199–215. http://dx.doi.org/10.1177/1461348417725944.
Повний текст джерелаАнотація:
Reducing the vibration of marine power machinery can improve warships' capabilities of concealment and reconnaissance. Being one of the most effective means to reduce mechanical vibrations, the active vibration control technology can overcome the poor effect in low frequency of traditional passive vibration isolation. As the vibrations arising from operation of marine power machinery are actually the frequency-varying disturbances, the H∞ control method is adopted to suppress frequency-varying disturbances. The H∞ control method can solve the stability problems caused by the uncertainty of the model and reshape the frequency response function of the closed loop system. Two-input two-output continuous transfer function models were identified by using the system identification method and are validated in frequency domain of which all values of best fit exceeds 89%. The method of selecting the weighting functions on the mixed sensitivity problem is studied. Besides, the H∞ controller is designed for a multiple input multiple output (MIMO) system to suppress the single-frequency-varying disturbance. The numerical simulation results show that the magnitudes of the error signals are reduced by more than 50%, and the amplitudes of the dominant frequencies are attenuated by more than 10 dB. Finally, the single excitation source dual-channel control experiments are conducted on the floating raft isolation system. The experiment results reveal that the root mean square values of the error signals under control have fallen by more 74% than that without control, and the amplitudes of the error signals in the dominant frequencies are attenuated above 13 dB. The experiment results and the numerical simulation results are basically in line, indicating a good vibration isolation effect.
16
Zhao, HM, DY Li, W. Deng, and XH Yang. "Research on vibration suppression method of alternating current motor based on fractional order control strategy." Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 231, no. 4 (March 8, 2016): 786–99. http://dx.doi.org/10.1177/0954408916637380.
Повний текст джерелаАнотація:
At present, the changing structure, material and increasing device are used to suppress the vibration of motor in general. These methods increase system complexity in the different degree. So a novel vibration suppression method based on fractional order Proportional-Integral-Derivative (PID) controller is proposed in this article. First, the digital realization process of fractional order PID controller is illustrated in detail. Then the integer order PID controller and fractional order PID controller are, respectively, used to adjust the input current of inverter to control the 1.5 kW alternating current motor. The vibration frequency spectrums and stator current frequency spectrums in low-frequency and carrier frequency band are, respectively, studied by using the comparison and analysis methods. At the same time, the vibration frequency spectrum and stator current frequency spectrum of 15 kW alternating current motor are compared and analyzed. And the frequency spectrums near the rotating frequency of stator current of 1.5 kW and 15 kW alternating current motors are amplified to deeply analyze spectrum characteristics. The experimental results show that the fractional order PID controller has the characteristics of multi-point control by comparing with the integer order PID controller. It changes the frequency components of stator current, and then the electromagnetic torque is more stable. So, the fractional order PID controller can better suppress the vibration of alternating current motor. The proposed method can provide a new idea for vibration suppression of rotating machinery.
17
Tanaka, N., and Y. Kikushima. "On the Hybrid Vibration Isolation Method." Journal of Vibration and Acoustics 111, no. 1 (January 1, 1989): 61–70. http://dx.doi.org/10.1115/1.3269824.
Повний текст джерелаАнотація:
For the purpose of isolating the vibration transmission from machines to soil and vice versa, this paper presents a new active vibration isolation method, that is, a hybrid vibration isolation method capable of isolating the vibration in the whole frequency range. The hybrid isolation method contains the following three characteristics: (1) a low-pass filter of a conventional elastic support method; (2) a high-pass filter of an active vibration isolation method; (3) suppression of a resonant peak due to an elastic support by a servo damper method; First, this paper presents the principle of the hybrid vibration isolation method and shows a fundamental structure of the system. Then by making the active isolator work as a damper, the suppression of a resonant peak due to an elastic support is achieved. Next, taking into consideration both the control effect and the stability of the system, the design procedure of the hybrid vibration isolation system is shown. Moreover, a control chart to estimate the control effect for suppressing the force transmissibility is presented. Finally, an experiment is carried out, demonstrating that the hybrid isolation method is capable of suppressing the exciting force in almost all the frequency range.
18
Xu, Fanghui, Dawei Dong, Bing Yan, Shizhe Song, Rui Zhang, and Yan Huang. "An abnormal vibration diagnosis and control method for internal combustion power plant." Journal of Physics: Conference Series 2184, no. 1 (March 1, 2022): 012012. http://dx.doi.org/10.1088/1742-6596/2184/1/012012.
Повний текст джерелаАнотація:
Abstract Focusing on the difficulty in vibration control of internal combustion power plant because of its diverse substructures and complex excitation, an abnormal vibration diagnosis and attenuation method based on the system’s whole-body vibration signals is proposed. The characteristics of the exciting forces, such as toppling torque, inertia force (or moment) and coupling centrifugal force, are analyzed. The resonance frequency distribution of the power unit is obtained by modal analysis. Then an expression that could reveal the relationship between the whole-body vibration intensity and the exciting force amplitude is established, and conclusion is drawn that different excitations would drive the system to vibrate at different frequencies. Based on this basic relation, a fault diagnosis method relying on comprehensive analysis of vibration signals in both time and frequency domain is proposed. Vibration attenuation methods targeted at specific faults are also put forward. Finally, the validity of the proposed method is verified by applying it to a 12V280 diesel generator set.
19
He, Shuilong, Tao Tang, Enyong Xu, Mingsong Ye, and Weiguang Zheng. "Vibration control analysis of vehicle steering system based on combination of finite-element analysis and modal testing." Journal of Vibration and Control 26, no. 1-2 (September 18, 2019): 88–101. http://dx.doi.org/10.1177/1077546319876798.
Повний текст джерелаАнотація:
Determining the natural frequency distribution is of great importance in studying the vibration of the steering system in a commercial vehicle. A high-speed vibration frequency sweep experiment on an unladen commercial vehicle was conducted to determine the resonance frequency of the vehicle components. A vibration waterfall plot of the collected vibration data revealed that the cause of the vibration was frequency coupling resonance between the steering wheel vibration frequency and the second-order rotation frequency of the tire. Thus, a combined optimization of the structure of the rigid bearing parts of the steering fixed support and the steering column structure was proposed. A combination of finite-element analysis and modal testing method was undertaken to verify the effectiveness of the proposed combined structural improvement; the results demonstrated the consistency of the combined methods and showed that the natural frequency of the improved steering structures, together with the vibration amplitude, had changed. This study demonstrated the feasibility of the combined modal testing and finite-element analysis method, provided more information on the vibration transfer characteristics related to the vehicle subsystems, and provided a reference for the structural design of steering systems with reduced vibration.
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Wang, Na, Yuan Du, Qingtao Gong, Ning Liu, and Yao Teng. "Research on the low-frequency multiline spectrum vibration control of offshore platforms." REVIEWS ON ADVANCED MATERIALS SCIENCE 61, no. 1 (January 1, 2022): 55–67. http://dx.doi.org/10.1515/rams-2021-0075.
Повний текст джерелаАнотація:
Abstract With the increasing scale, complexity and diversity of supporting equipment of offshore platform, the low-frequency vibration of equipment such as dynamic positioning system and the main engine is difficult to attenuate in the propagation process of the platform structure, which causes a local resonance of platform, aggravates the fatigue damage of structure and causes discomfort to the human body. Dynamic vibration absorption is widely used in the low-frequency vibration control of offshore platforms; however, there is little research about the multiline spectrum vibration control method in the local resonance region of platforms. In the current research, we first take the stiffened plate under multipoint excitation as the research object, and the effectiveness of the optimal homology design method of dynamic vibration absorption is verified. Subsequently, the low-frequency multiline spectrum vibration control method about the local resonance region of the offshore platform is proposed. Finally, a large offshore platform is chosen as the research object and the measured load of the main engine is taken as the input to calculate the vibration response of the platform. The effect of distributed dynamic vibration absorption of the resonance area verifies the effectiveness of the vibration control method presented in the article and provides a basis for the engineering application.
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Ying, Zu-Guang, and Yi-Qing Ni. "Vibrational Amplitude Frequency Characteristics Analysis of a Controlled Nonlinear Meso-Scale Beam." Actuators 10, no. 8 (August 3, 2021): 180. http://dx.doi.org/10.3390/act10080180.
Повний текст джерелаАнотація:
Vibration response and amplitude frequency characteristics of a controlled nonlinear meso-scale beam under periodic loading are studied. A method including a general analytical expression for harmonic balance solution to periodic vibration and an updated cycle iteration algorithm for amplitude frequency relation of periodic response is developed. A vibration equation with the general expression of nonlinear terms for periodic response is derived and a general analytical expression for harmonic balance solution is obtained. An updated cycle iteration procedure is proposed to obtain amplitude frequency relation. Periodic vibration response with various frequencies can be calculated uniformly using the method. The method can take into account the effect of higher harmonic components on vibration response, and it is applicable to various periodic vibration analyses including principal resonance, super-harmonic resonance, and multiple stationary responses. Numerical results demonstrate that the developed method has good convergence and accuracy. The response amplitude should be determined by the periodic solution with multiple harmonic terms instead of only the first harmonic term. The damping effect on response illustrates that vibration responses of the nonlinear meso beam can be reduced by feedback control with certain damping gain. The amplitude frequency characteristics including anti-resonance and resonant response variation have potential application to the vibration control design of nonlinear meso-scale structure systems.
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Qiu, Zhi-Cheng, and Si-Ma Zhang. "RBF neural network-based sliding mode vibration control of a flexible cantilever plate using laser displacement measurement." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 231, no. 8 (June 14, 2016): 1492–508. http://dx.doi.org/10.1177/0954410016654182.
Повний текст джерелаАнотація:
This paper is concerned with active vibration control of a flexible piezoelectric cantilever plate using a nonlinear radial basis neural network sliding mode control (RBFNN-SMC) algorithm and laser displacement measurement. In order to decouple the low-frequency vibration signals of the bending and torsional modes on measurement, two laser displacement sensors are used. The decoupling method is provided. A hyperbolic tangent function is used instead of the sign function, and the chattering phenomenon is alleviated. Also, the RBFNN is utilized to adjust the switching control gain adaptively to balance the chattering phenomenon and the control effect. The controllers for bending and torsional modes are designed independently. Experimental setup of the flexible piezoelectric cantilever plate with two laser displacement sensors is constructed. Experiments on vibration measurement and control are conducted by using the decoupling method and the designed controller, compared with the classical proportional and derivative (PD) control algorithm. The experimental results demonstrate that the proposed method can decouple the low-frequency bending and torsional vibration signals on measurement. Furthermore, the designed nonlinear RBFNN-SMC can suppress both the bending and torsional vibrations more quickly than the traditional linear PD controller, especially for the small amplitude residual vibration.
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Hong, Dongwoo, and Byeongil Kim. "Quantification of Active Structural Path for Vibration Reduction Control of Plate Structure under Sinusoidal Excitation." Applied Sciences 9, no. 4 (February 18, 2019): 711. http://dx.doi.org/10.3390/app9040711.
Повний текст джерелаАнотація:
The engines of electric and hybrid vehicles cause vibration and noise with complex frequency spectra. This tendency is observed especially for mid-frequency components. Therefore, there are limitations in achieving vibration attenuation using only structural changes, which is the conventional isolation method. A smart structure-based active engine mounting system is a core technology that can continuously improve the noise, vibration, and harshness performance under various operating conditions by continuously controlling the dynamic characteristics of the mount. It can replace the existing mount technology which supports the engine by realizing both static and dynamic stiffness. This study focuses on vibration reduction for a typical mid-frequency excitation. Based on a source–path–receiver structure, a mathematical model for a 3D plate structure with three active paths is proposed. The amplitude and phase of the actuator were calculated for the reduction of given vibrations on the basis of the model. When controlling with the proposed method, it was necessary to perform a large amount of computation and to newly define the modeling according to the structural change. To solve this inconvenience, the NLMS (normalized least mean squares) algorithm was applied, and the results were compared. It is shown that the application of the NLMS algorithm to perform the overall vibration reduction is more effective than the previous method.
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Yaroshenko, Leonid, Roman Chubyk, and Iryna Derevenko. "JUSTIFICATION OF PARAMETERS OF THE CONTROL SYSTEM OF ELECTROMECHANICAL DEBALANCE VIBRODRIVE OF VIBRATION MACHINES ON THE BASIS OF ARTIFICIAL NEURAL NETWORK." Vibrations in engineering and technology, no. 3(102) (September 28, 2021): 52–63. http://dx.doi.org/10.37128/2306-8744-2021-3-6.
Повний текст джерелаАнотація:
The article analyzes and proposes an approach to the construction of a control system for electromechanical debalance vibrodrive for vibration machines based on an artificial neural network. As a result of the analysis of various methods of managing dynamic objects it is concluded that the most appropriate and perfect for this type of machine is neurocontrol method of predictive model neurocontrol, which allows to expand the functionality of these vibrating machines and significantly save energy for vibratory drive of their oscillations. A direct neuro-emulator is used to predict the future behavior of the oscillating mechanical system of the vibration technological machines and to calculate errors. An important feature of the predictive neurocontrol model in the proposed method of controlling the operation of vibrating technological machines using an artificial neural system is that there is no neurocontroller that needs to be trained, its place is taken by the optimization algorithm. Applying the proposed method of controlling operation of adaptive vibration technology machines using artificial neural network will optimize the electromechanical control of debalanced vibration drive of vibrating machines and provide optimal resonant modes of its operation (which is energy efficient) in all technological modes of vibrating operation. The technical and economic characteristics of this control method are further improved due to the fact that the proposed control method uses the technology of predictive model neurocontrol and as a result is constantly calculated (forecasted) several cycles in advance and determines the best strategy to control the frequency of forced cyclic vibration. As a result, the mechanical system of vibration machines spends less time in non-resonant mode. This method of control also minimizes the duration of transients when changing the load mass of the working body vibration or changing the mode of vibration parameters and the parameters of their technological process.
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Jianfei, Yao, Gao Jinji, and Wang Weimin. "Multi-frequency rotor vibration suppressing through self-optimizing control of electromagnetic force." Journal of Vibration and Control 23, no. 5 (August 9, 2016): 701–15. http://dx.doi.org/10.1177/1077546315586301.
Повний текст джерелаАнотація:
In this paper, the attention is confined to the suppression of multi-frequency rotor vibration. A method to control rotor’s multi-frequency periodic vibration in rotor-bearings system is proposed which uses active magnetic exciter (AME) to produce active control force to suppress rotor’s vibration and to reach a self-optimizing control of the rotor vibration. The control strategies include an arithmetic to optimize the amplitudes and phases of the control current using on-line self-optimizing algorithms in AME and applied multiple frequency-matched control force that AME generates to reduce the measured amplitudes of rotor. The model of rotor-bearings system with AME is established firstly. An active vibration control scheme for controlling transverse vibration of the rotor due to multi-frequency excitation is designed. The whole circle search algorithm and fast optimizing search algorithm about the amplitude and phase of control current are proposed. Finally, the experiments for controlling multi-frequency vibration of the rotor are carried out on the rotor-bearings test rig. The experimental results indicate that the proposed method can effectively suppress the rotor vibration for multi-frequency components through self-optimizing control of electromagnetic force.
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Cui, Rixin. "Integrated design of passive control methods for mitigating vibration and noise of rails in high-speed railway." Noise Control Engineering Journal 70, no. 1 (January 1, 2022): 90–100. http://dx.doi.org/10.3397/1/37707.
Повний текст джерелаАнотація:
Attachment of constrained layer dampers and dynamic vibration absorbers (DVAs) on rails are two effective passive control methods used for mitigating vibration and noise of railways at the source. An integrated passive control method in which constrained layer dampers and DVAs were simultaneously attached on the rail was proposed to attenuate the vibration and noise of the rail in a broad frequency range and to suppress the maximum vibration emitted by the first pinned-pinned resonance of the rail. The design method for the integrated application was developed based on the optimum design theory of DVA for multiple-degree-of-freedom damping structures. The vibration and noise reduction properties of the integrated control method were analyzed using a vibroacoustic model established based on the sequential finite element method–boundary element method and evaluated through laboratory tests. The results show that the integrated control method fully demonstrates the advantages of the two passive vibration control methods, which can improve the longitudinal transmission loss of the rail by 5.3 dB/m at the first pinned-pinned resonant frequency and reduce the maximum acoustic power of the rail by 7.8 dB(A) as well as achieve an overall rail noise reduction of 4.0 dB(A) within 3000 Hz. The vibration and noise reduction properties of the integrated control method are improved as the mass ratio increases in the frequency range above 600 Hz. The test results show that the integrated control method decreases the rail web vibration and rail noise by more than 40%.
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Hao, Donghao, Changlu Zhao, and Ying Huang. "A Reduced-Order Model for Active Suppression Control of Vehicle Longitudinal Low-Frequency Vibration." Shock and Vibration 2018 (2018): 1–22. http://dx.doi.org/10.1155/2018/5731347.
Повний текст джерелаАнотація:
Establishing a prediction model, with linearity and few dof (degree of freedom), is a key step for the design of a control algorithm based on the modern control theory. In this paper, such a model is needed for active suppression of vehicle longitudinal low-frequency vibration. However, many dynamic processes in the vehicle have different effects on the vibration. Therefore, a detailed coupling model is firstly established, considering the dynamics of the torsional vibrations of the driveline and the tire, the tire force nonlinearity, and the vehicle vertical and pitch vibrations. Based on this model, sensitivity analysis is conducted and the results show that the tire slip, the torsional stiffness of the half-shaft, and the tire have great influences on the longitudinal vibration. Then a three-dof model is obtained by linearizing the tire slip into damping. A parameter estimation method is designed to obtain the model parameters. Finally, the model is validated. The time domain response, error analysis, and frequency response results demonstrate that the 3-dof model has a good consistency with the detailed coupling model. It is suitable as a control-oriented model.
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Qin, Hui, Hongbo Zheng, Wenyuan Qin, and Zhiyi Zhang. "Lateral vibration control of a shafting-hull coupled system with electromagnetic bearings." Journal of Low Frequency Noise, Vibration and Active Control 38, no. 1 (November 18, 2018): 154–67. http://dx.doi.org/10.1177/1461348418811516.
Повний текст джерелаАнотація:
In order to suppress lateral vibration transmission and reduce acoustic radiation of a shafting-hull coupled system, a new approach using electromagnetic bearings in the shafting system is proposed. The dynamic characteristics of the electromagnetic bearings, especially the equivalent stiffness and damping as well as the applicable scope of linearization of the electromagnetic bearings, are analysed at first. With the equivalent parameters, a dynamic model of the shafting-hull coupled system is established subsequently by using the frequency response synthesis method to derive frequency response functions associated with the lateral vibrations. Finally, the influence of the control parameters of the electromagnetic bearings on vibration transmission in the shafting-hull system is studied. Analysis results indicate that lateral vibration responses are suppressed significantly when electromagnetic bearings are introduced into the shafting-hull system, and as a result, sound radiation of the system is reduced, which demonstrates that the proposed approach is effective in controlling vibration transmission in the shafting system.
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Zhou, Mengde, Wei Liu, Qinqin Wang, Bing Liang, Linlin Tang, Yang Zhang, and Xiaochun Cui. "A Decoupled Unified Observation Method of Stochastic Multidimensional Vibration for Wind Tunnel Models." Sensors 20, no. 17 (August 20, 2020): 4694. http://dx.doi.org/10.3390/s20174694.
Повний текст джерелаАнотація:
Active vibration control is the most effective method for stochastic multidimensional vibration in wind tunnel tests, in which vibration monitoring is the core foundation. Vibrations are induced by the disturbances of several complex air flow instabilities under extreme test conditions with high attack angles. Here, a decoupled unified observation method is proposed in order to fully monitor stochastic multidimensional vibration. First, stochastic multidimensional vibration is explained using the Cartesian coordinate system. Then, the multidimensional vibration decoupling of the pitch plane and the yaw plane is realized according to the proposed decoupling design principle of the long cantilever sting. A unified observation method is presented, based on inertial force theory, to observe multidimensional vibration due to acceleration in each decoupling plane. Verification experiments were conducted in lab and a transonic wind tunnel, using an established real-time monitoring system. The results of lab experiments indicate that, in the frequency region of 0–120 Hz, three vibration modes of a selected stochastic vibration can be decoupled and observed through the vibration components in pitch plane and yaw plane. In addition, wind tunnel tests were carried out according to the working conditions (α = −4~10° with γ = 45°) at Ma = 0.6 and Ma = 0.7, respectively. The results show that six vibration modes of two selected stochastic vibrations can be decoupled and observed through the vibration components in pitch plane and yaw plane. The experimental results prove that stochastic vibration can be fully monitored in multiple dimensions through the vibration components in pitch plane and yaw plane using the proposed decoupled unified observation method. Therefore, these results lay the foundation for active vibration control.
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She, Tian Li, Feng Gao, and Shu Lin Ma. "The Application of Negative Feedback to Active Control in Vibration Isolation." Applied Mechanics and Materials 511-512 (February 2014): 1068–71. http://dx.doi.org/10.4028/www.scientific.net/amm.511-512.1068.
Повний текст джерелаАнотація:
Ultralow frequency vibration tables can easily be imposed external vibration interferences when they work. These interferences result to output distortion and the reduction of the calibration precision. A system with active vibration isolation control can effectively reduce the measure distortion. The principle of active control is the negative feedback method in vibration isolation. A composite feedback system was introduced that based on several different feedback variables. The frequency characteristic of the system was analysed. We simulated MATLAB at 0.1Hz and 1Hz. It is obvious that a better vibration isolation is effective by composite feedback system based on negative feedback method.
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Liu, Youyong, He Wen, Zongying Ding, Lei Xu, Hongjiang Chen, and Janusz Smulko. "An Instantaneous Engine Speed Estimation Method Using Multiple Matching Synchrosqueezing Transform." Journal of Sensors 2021 (April 8, 2021): 1–11. http://dx.doi.org/10.1155/2021/6650432.
Повний текст джерелаАнотація:
Instantaneous rotational speed measurement of the engine is crucial in routine inspection and maintenance of an automobile engine. Since the contact measurement of rotational speed is not always available, the vibration measurement has been used for noncontact rotational speed estimation methods. Unfortunately, the accuracy of the noncontact estimation methods by analyzing engine vibration frequency is not satisfactory due to the influence of noise and the strong nonstationary characteristic of the vibration signal. To overcome these problems, based on the multiple matching synchrosqueezing transform (MSST) (MMSST, improved MSST with multiple squeeze operations), a novel noncontact method is proposed to accurately estimate the instantaneous rotational speed of automobile engine in this paper. Firstly, a MMSST is proposed to process the vibration signal to obtain a concentrated time-frequency (TF) representation. Secondly, the instantaneous frequency (IF) detection algorithm is employed to extract the fundamental frequency from the TF result. Finally, the rotational speed of the engine is calculated according to the relationship between the fundamental frequency and rotational speed. Results from numerical simulations and test on real engine have proven that the proposed method can obtain much higher frequency resolution and more precise IF estimation of the engine vibration signal and more accurate rotational speed estimation result compared with the MSST method. Furthermore, the proposed method is verified to have a stronger noise robustness and can provide satisfactory estimation results for engine vibration signal containing nonlinear frequency-modulated components.
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Zhang, Xing Wu, Xue Feng Chen, Shang Qin You, Xiao He, Yi Jie Wang, and Zheng Jia He. "Study on Active Control of Structural Frequency Response." Advanced Materials Research 199-200 (February 2011): 1036–40. http://dx.doi.org/10.4028/www.scientific.net/amr.199-200.1036.
Повний текст джерелаАнотація:
As the requirements for industrial operation and military work, the frequency characteristics should be changed artificially sometimes. Active control is a good choice, but the current active control mainly focuses on time domain for vibration control. In this paper, the structural active control on frequency domain is studied through theory and experiment. Firstly, multivariable wavelet finite element method with two kinds of variables (TWFEM) which is suitable for modeling of great and complex structures with high efficiency and precision is used to construct the mathematical model for the controlled structure and do static and dynamic analysis. Then the control algorithm based on neural network including two parts, identification implement and controller is constructed. The present study takes frequency response as control objective, and can not only do vibration control but also change the vibration frequency characteristics, providing a new perspective for active control.
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Gong, Fei, Songlin Nie, Hui Ji, Ruidong Hong, Fanglong Yin, and Xiaopeng Yan. "Pipeline Vibration Control Using Magnetorheological Damping Clamps under Fuzzy–PID Control Algorithm." Micromachines 13, no. 4 (March 28, 2022): 531. http://dx.doi.org/10.3390/mi13040531.
Повний текст джерелаАнотація:
Aiming at the problem of low-frequency vibration of the hydraulic pipeline, a new type of semi-active damping magnetorheological (MR) damping clamp structure is designed. The structure size and material of the MR damping clamp were determined. The control model of the vibration damping system was established, and the control method combining fuzzy control and Proportional-Integral-Derivative (PID) control was used to carry out the numerical simulation, which proved that the fuzzy–PID control algorithm is effective and stable. The results show that the MR damping clamp proposed in this paper can effectively suppress the axial displacement and acceleration of the hydraulic pipeline in the excitation frequency range of 1 Hz~10 Hz. This research provides a new technical approach for low-frequency vibration control of hydraulic pipelines.
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Gosiewski, Zdzisław, and Andrzej Piotr Koszewnik. "Modeling of Beam as Control Plane for a Vibration Control System." Solid State Phenomena 144 (September 2008): 59–64. http://dx.doi.org/10.4028/www.scientific.net/ssp.144.59.
Повний текст джерелаАнотація:
An active vibration damping system with the use of piezoelements fixed to the structure is presented in the paper. The optimal location of the piezo-stripes on the structure is calculated for given cost functions. Coefficient correlations between control forces, strains, mode shapes, frequency changes, modal masses and modal stiffness are analyzed in order to find simpler method for calculation of the quasi-optimal localization of piezo-sensors and piezo-actuators. Reduced model of the open-loop system was identified and the simulations were carried out in order to find the best controller to reduce the amplitude of vibrations. The correctness of the selection of the controller was verified and investigated experimentally.
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Peng, Lijuan, Jian Wang, Guicheng Yu, Zuoxue Wang, Aijun Yin, and Hongji Ren. "Active Vibration Control of PID Based on Receptance Method." Journal of Sensors 2020 (August 14, 2020): 1–8. http://dx.doi.org/10.1155/2020/8811448.
Повний текст джерелаАнотація:
Active vibration control approaches have been widely applied on improving reliability of robotic systems. For linear vibratory systems, the vibration features can be altered by modifying poles and zeros. To realize the arbitrary assignment of the closed-loop system poles and zeros of a linear vibratory system, in this paper, an active PID input feedback vibration control method is proposed based on the receptance method. The establishment and verification of the proposed method are demonstrated. The assignable poles during feedback control are calculated and attached with importance to expand the application of the integral control. Numerical simulations are conducted to verify the validity of the proposed method in terms of the assignment of closed-loop poles, zeros, and both. The results indicate that the proposed method can be used to realize the active vibration control of closed-loop system and obtain the desired damping ratio, modal frequency, and dynamic response.
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Li, Chao, and Zhangwei Chen. "A fast vibration-level adjustment method for low-frequency vibration calibration based on modified filtered-x least mean square algorithm." Measurement and Control 53, no. 3-4 (January 7, 2020): 328–38. http://dx.doi.org/10.1177/0020294019881727.
Повний текст джерелаАнотація:
Traditionally, successive approximation method is applied to the vibration-level adjustment of vibration calibration system, which leads to a time-consuming work for low-frequency vibration calibration. In this paper, a novel control method for low-frequency vibration calibration system is proposed based on adaptive filter. First, the problem of the traditional vibration-level adjustment for low-frequency signals is depicted. Then, an adaptive control algorithm is presented, in which the control input is composed of two weighted sinusoidal signals with a phase difference of 90°. The weighted vector is updated in real time using a modified filtered-x least mean square algorithm. Unlike filtered-x least mean square algorithm, the proposed modified filtered-x least mean square algorithm does not require a pre-identification of the controlled system and has a reduced computational complexity. The convergence property of the proposed method is analyzed in detail. Finally, the proposed method is implemented on a low-frequency vibration calibration system. Experimental results show that the proposed modified filtered-x least mean square algorithm can significantly reduce the time of the vibration-level adjustment in low-frequency band.
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Ren, Yan, Jian Ruan, and Ji Yan Yi. "Separate Control Characteristics of Electro-Hydraulic Vibrator Using a Parallel Mechanism." Advanced Materials Research 199-200 (February 2011): 953–57. http://dx.doi.org/10.4028/www.scientific.net/amr.199-200.953.
Повний текст джерелаАнотація:
A scheme of the separate control technique of electro-hydraulic vibrator is proposed, in which symmetrical hydraulic cylinder is controlled by a parallel mechanism of a two-dimensional valve (named as 2D valve) and a parallel servo valve. The working frequency and vibration amplitude of the electro-hydraulic vibrator are dominated by the rotary speed and the sliding displacement of the spool of the 2D valve respectively, and the vibration central piston is controlled by the sliding displacement of the spool of the parallel servo valve. This paper analyzes the relationship between vibration characteristic values and control parameters using the analytic method based on the hydrodynamic control theory. The experimental system is built to verify that the theoretical analysis is consistent with measured results.
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Zhao, Hui, Haisen Li, Yan Wang, Zhenjun Liu, Jiacong Bian, and Jianguo Chen. "A Thickness-Mode High-Frequency Underwater Acoustic Transducer with a Low Sidelobe Level." Actuators 10, no. 9 (September 8, 2021): 226. http://dx.doi.org/10.3390/act10090226.
Повний текст джерелаАнотація:
Thickness vibration mode is commonly used for high-frequency transducers. For disc piezoelectric ceramics, there is no ideally pure thickness vibration mode because the coupling between the radial and thickness modes always exists. Furthermore, it also deteriorates the transmission voltage response and directivity of the high-frequency transducer. In this paper, based on the theoretical calculation and finite element simulation method, a new method was proposed, and the related experiment was carried out to convince this idea. Both the simulation analysis and experimental results show that drilling a hole at the center of piezoelectric vibration is a simple but effective method to obtain a pure thickness vibration mode of the disc piezoelectric ceramic, and then improve the transmitting ability and directivity of the high-frequency piezoelectric transducer. The sidelobe level is as low as −21.3 dB.
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Qiu, Zhi-cheng, and Tao-xian Wang. "Fuzzy neural network vibration control on a piezoelectric flexible hinged plate using stereo vision detection." Journal of Intelligent Material Systems and Structures 30, no. 4 (January 8, 2019): 556–75. http://dx.doi.org/10.1177/1045389x18818766.
Повний текст джерелаАнотація:
Vibration control on a two-connected piezoelectric flexible hinged plate is investigated, using a fuzzy neural network algorithm based on binocular vision measurement. As for vision sensing, a method to acquire vibration signals of the low frequency bending and torsional mode is investigated. To damp out the residual vibration quickly, the fuzzy neural network is applied to ensure the stability and control effect adaptively. To verify the stereo vision measurement method and the applied controller, an experimental setup of the piezoelectric flexible hinged plate with a binocular stereo vision is constructed. Experiments are conducted by using the binocular stereo vision measurement system and the adopted controller. The experimental results demonstrate the feasibility of the visual measurement method. Furthermore, the designed fuzzy neural network can attenuate the bending and torsional vibrations quickly, in comparison with proportional and derivative control, particularly for the small-level residual vibration.
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Wang, Jia Dian, Chong Liu, and Xiao Zeng Xie. "Vibration Analysis of the Control Valve Coupled Models." Advanced Materials Research 955-959 (June 2014): 894–98. http://dx.doi.org/10.4028/www.scientific.net/amr.955-959.894.
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A marine steam turbine control valve is taken as the research object in this paper, the vibration response is studied under pressure pulse excitation. The transient flow field analysis is made using the method of large eddy simulation to obtain the time-domain information of the pressure pulsation. Then, the analysis of vibration based on coupled modes, research vibration response and resonance problems of the control valve. The study found that the vibration of control valve is strongly in low frequency excitation, but high-frequency excitation makes relatively little impacts on it; The diffuser and downstream of valve is the main area of generating vibration.
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Liu, Yun-Hui. "Application of a Proportional Feedback Controller for Active Control of a Vibration Isolator." Journal of Low Frequency Noise, Vibration and Active Control 24, no. 3 (September 2005): 181–90. http://dx.doi.org/10.1260/026309205775374442.
Повний текст джерелаАнотація:
This paper proposes the application of a proportional controller to active vibration control incorporated with a passive vibration isolator to suppress its resonant oscillation at its natural frequency. Vibration acceleration acquired from an accelerometer is fed to the controller as a feedback signal. The processed signal from the controller is transmitted to the voice coil actuator in order to control the vibration. Firstly, based on the theoretical equations which govern the vibrational system, the physical mechanism of active control in the total system is studied. Then, vibration on a stiff foundation and passive isolator is measured in order to understand the efficiency of the traditional vibration control method. Finally, an experiment on active vibration control is performed to study the suppression efficiency of the oscillation of the passive vibration isolator. The experiment results show that 99% of the vibration energy can be cancelled by active control.
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Shan, Xiaobiao, Henan Song, Chong Zhang, Guangyan Wang, and Jizhuang Fan. "Linear System Identification and Vibration Control of End-Effector for Industrial Robots." Applied Sciences 10, no. 23 (November 29, 2020): 8537. http://dx.doi.org/10.3390/app10238537.
Повний текст джерелаАнотація:
This paper presents the discrete state space mathematical model of the end-effector in industrial robots and designs the linear-quadratic-Gaussian controller, called LQG controller for short, to solve the low frequency vibration problem. Though simplifying the end-effector as the cantilever beam, this paper uses the subspace identification method to determine the output dynamic response data and establishes the state space model. Experimentally comparing the influences of different input excitation signals, Chirp sequences from 0 Hz to 100 Hz are used as the final estimation signal and the excitation signal. The LQG controller is designed and simulated to achieve the low frequency vibration suppression of the structure. The results show that the suppression system can effectively suppress the fundamental natural frequency and lower vibration of end-effector. The vibration suppression percentage is 95%, and the vibration amplitude is successfully reduced from ±20 μm to ±1 μm. The present work provides an effective method to suppress the low frequency vibration of the end-effector for industrial robots.
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Yin, Zhaoqin, Zemin Huang, Xiaohui Lin, Xiaoyan Gao, and Fubing Bao. "Droplet Generation in a Flow-Focusing Microfluidic Device with External Mechanical Vibration." Micromachines 11, no. 8 (July 30, 2020): 743. http://dx.doi.org/10.3390/mi11080743.
Повний текст джерелаАнотація:
The demand for highly controllable droplet generation methods is very urgent in the medical, materials, and food industries. The droplet generation in a flow-focusing microfluidic device with external mechanical vibration, as a controllable droplet generation method, is experimentally studied. The effects of vibration frequency and acceleration amplitude on the droplet generation are characterized. The linear correlation between the droplet generation frequency and the external vibration frequency and the critical vibration amplitude corresponding to the imposing vibration frequency are observed. The droplet generation frequency with external mechanical vibration is affected by the natural generation frequency, vibration frequency, and vibration amplitude. The droplet generation frequency in a certain microfluidic device with external vibration is able to vary from the natural generation frequency to the imposed vibration frequency at different vibration conditions. The evolution of dispersed phase thread with vibration is remarkably different with the process without vibration. Distinct stages of expansion, shrinkage, and collapse are observed in the droplet formation with vibration, and the occurrence number of expansion–shrinkage process is relevant with the linear correlation coefficient.
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Ezure, Katsuhiko, Kazuto Seto, Sinji Mitsuta, and Katsumi Sawatari. "Active Vibration Control of Flexible Structures Arranged in Parallel." Journal of Robotics and Mechatronics 6, no. 3 (June 20, 1994): 243–48. http://dx.doi.org/10.20965/jrm.1994.p0243.
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This paper proposes a vibration control method for flexible structures arranged in parallel. In recent years, tall buildings equipped with active dynamic absorbers have been popularized to maintain living comfort by reducing the vibration of higher floors by strong winds. The higher a tall building the lower its natural frequency. It will be difficult to control the vibration of ultra-tall buildings using active dynamic absorbers because of difficulties in obtaining enough control force under the lower frequency. According to the proposed method, a pair of flexible buildings are controlled actively by controlling each other by means of actuators placed between them. Therefore, it is able to obtain enough control force under the low frequency. In this paper, a reduced-order model expressed by 2DOF systems is proposed for preventing spillover instability. The LQ control theory is applied to the design of the control system. The effectiveness of this method is demonstrated theoretically as well as experimentally.
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Hou, Dongxiao. "Vertical Vibration Control of Cold Rolling Mill’s Rolls Based on Time-delay Feedback Control Method." MATEC Web of Conferences 153 (2018): 06005. http://dx.doi.org/10.1051/matecconf/201815306005.
Повний текст джерелаАнотація:
In this paper, a two degree of freedom nonlinear vertical vibration equation of the cold rolling mill with the dynamic rolling force was established, then the delay feedback control method was introduced into the equation to controlled the vertical vibration of the system. The amplitude-frequency equations of primary resonance of system was carried out by using the multi-scale method, and the resonance characteristics of different parameters of delay feedback control method were obtained by adopting the actual parameters of rolling mill. It is found that the size of the resonance amplitude value was effectively controlled and the resonance region and jumping phenomenon of the system were eliminated by selecting the appropriate time-delay parameters combination, which provides an effective theoretical reference for solving mill vibration problems.
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Ying, Zu-Guang, and Yi-Qing Ni. "A multimode perturbation method for frequency response analysis of nonlinearly vibrational beams with periodic parameters." Journal of Vibration and Control 26, no. 13-14 (December 18, 2019): 1260–72. http://dx.doi.org/10.1177/1077546319892429.
Повний текст джерелаАнотація:
A multimode perturbation method for frequency response analysis of nonlinearly vibrational beams with periodic distribution parameters is proposed. The partial differential equation with spatial varying parameters for nonlinear vibration of beams with periodic parameters under harmonic excitations is derived. The procedure of the multimode perturbation method includes three main steps: first, the nonlinear partial differential equation is transformed into linear partial differential equations with varying parameters by applying perturbation method; second, the linear partial differential equations are transformed into ordinary differential equations with multimode coupling by applying Galerkin method, where multiple vibration modes of the beams are used and the equations are suitable to nonlinear vibration of periodic structures with high parameter-varying wave in wide frequency band; third, the ordinary differential equations are solved by applying harmonic balance method to obtain vibration response of the nonlinear periodic beam, which is used for characteristics analysis of frequency response and spatial mode. Furthermore, the stability problem of nonlinear harmonic vibration as multidegree-of-freedom system with periodic time-varying parameters is solved by applying direct eigenvalue analysis approach. The proposed method can incorporate multiple vibration modes into response analysis of nonlinear periodic structures and consider mode-coupling effects due to structural nonlinearity and parametric periodicity. Finally, a nonlinear beam with periodic supports under harmonic excitations is studied. Numerical results on frequency response of the beam are given to illustrate an application of the proposed method, new frequency response characteristics, and influences of periodic parameters on structural response. The results have potential application to nonlinear structural vibration control and support damage detection of nonlinear structures with periodic supports.
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Li, Jian Liang, Xiao Xi Liu, Shu Qing Li, Zhi Fei Tao, and Lei Ma. "Research on Vibration Isolation System Based on Disturbance Observer PID Control Algorithm." Applied Mechanics and Materials 865 (June 2017): 480–85. http://dx.doi.org/10.4028/www.scientific.net/amm.865.480.
Повний текст джерелаАнотація:
The research mainly focuses on the performance of the controllable hypocenter in the low frequency band. The hybrid vibration isolation method based on the disturbance observer PID control algorithm is used to improve the excitation signal quality. Based on the analysis of the structure and working principle of vibration isolator, the physical model and mathematical model are established, and the simulation test of ZK-5VIC virtual test vibration and control system is carried out. The experimental platform of hybrid vibration isolation system with low frequency interference is set up. The experiment of excitation and acquisition of low frequency signal is carried out, which provides the theoretical basis and guarantee for the vibration isolation technology in the low frequency range below 3Hz.
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Wang, Xi. "Coarse-Fine Self-Learning Active Mass Damper for Frequency Tracking Vibration Control." International Journal of Structural Stability and Dynamics 20, no. 02 (January 14, 2020): 2050024. http://dx.doi.org/10.1142/s0219455420500248.
Повний текст джерелаАнотація:
This paper presents a coarse-fine self-learning active mass damper (AMD) for frequency tracking vibration control. Even though the AMD is under unknown disturbance, it can obtain the exact exciting frequency of primary system after several self tries and achieve significant vibration suppression. The frequency tuning algorithm consists of two improved techniques, namely, the variable-gain frequency estimator and variable learning rate [Formula: see text]-learning algorithm, both aim to accelerate the convergence speed of frequency estimation. The coarse tuning method helps to tune the AMD’s natural frequency in a relatively wide effective bandwidth using frequency estimator and the fine tuning method can achieve precise tune in a tiny-scale bandwidth. The simulation results demonstrate that this coarse-fine learning AMD can help obtain the exact exciting frequency after several times of self-learning, and the vibration of primary system is dramatically attenuated by tuning the AMD’s natural frequency to match with the exciting frequency. This is the first time for the tuning method of mass damper proposed using machine learning, which can help obtain the exact exciting frequency after several self-tries.
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Muthalif, Asan G. A., and Robin S. Langley. "Active control of high-frequency vibration: Optimisation using the hybrid modelling method." Journal of Sound and Vibration 331, no. 13 (June 2012): 2969–83. http://dx.doi.org/10.1016/j.jsv.2012.02.012.
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Lee, Ill-Yeong, Man-Gon Kang, and Sae-Ryung Choi. "2D33 A method for measuring frequency series wave speed in viscoelastic pipes(The 12th International Conference on Motion and Vibration Control)." Proceedings of the Symposium on the Motion and Vibration Control 2014.12 (2014): _2D33–1_—_2D33–8_. http://dx.doi.org/10.1299/jsmemovic.2014.12._2d33-1_.
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