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This paper aims to present a multi-axis actuating approach to attenuate the bending and torsional vibration of the solar array through the reaction wheel (RW) actuators.

The motion equation of the solar array with the RW actuators is derived in modal coordinates for controller design. The reaction torques, induced by the speed change of the RW actuators, are controlled for vibration attenuation through the constraints on the actuators’ rotating speed. The proposed control approach is firstly verified with numerical simulation on the finite element model of a full-scale solar array. Experimental study of a simplified elastic plate model is subsequently performed for feasibility and validity investigation.

Both the numerical and experimental studies demonstrated the success of adopting RW as the actuator. Results from numerical simulation reveal that the vibration response peak can be reduced by 80% with 2% of mass increase by using the RW actuators.

It is demonstrated that the multi-axis actuating method using RW actuators has a great potential in vibration attenuation of the multi-panel deployable solar array.

An approach to reduce bending and torsional vibration of solar array based on RW actuators is investigated. Theoretical analysis, numerical simulation and experimental study are conducted to demonstrate the validity of the proposed vibration attenuation approach and its potential application in the spacecraft design.

The purpose of this paper is to study the preload range of tendon-driven manipulator and the relationship between preload and damping. The flexible joint manipulator (FJM) with joint flexibility is safer than traditional rigid manipulators. A FJM having an elastic tendon is called an elastic tendon-driven manipulator (ETDM) and has the advantages of being driven by a cable and having a more flexible joint. However, the elastic tendon introduces greater residual vibration, which makes the control of the manipulator more difficult. Accurate dynamic modeling is effective in solving this problem.

The present paper derives the relationship between the preload of the ETDM and the friction moment through the analysis of the forces of cables and pulleys. A dynamic model dominated by Coulomb damping is established.

The linear relationship between a decrease in the damping moment of the system and an increase in the ETDM preload is verified by mechanics analysis and experiment, and a curve of the relationship is obtained. This study provides a reference for the selection of ETDM preload.

The method to identify ETDM damping by vibration attenuation experiments is proposed, which is helpful to obtain a more accurate dynamic model of the system and to achieve accurate control and residual vibration suppression of ETDM.

This study aims to explore an active control strategy for attenuation of in-line and transverse flow-induced vibration (FIV) of two tandem-arranged circular cylinders.

The control system is based on the rotary oscillation of cylinders around their axis, which acts according to the lift coefficient feedback signal. The fluid-solid interaction simulations are performed for two velocity ratios (V_r = 5.5 and 7.5), three spacing ratios (L/D = 3.5, 5.5 and 7.5) and three different control cases. Cases 1 and 2, respectively, deal with the effect of rotary oscillation of front and rear cylinders, while Case 3 considers the effect of applied rotary oscillation to both cylinders.

The results show that in Case 3, the FIV of both cylinders is perfectly reduced, while in Case 2, only the vibration of rear cylinder is mitigated and no change is observed in the vortex-induced vibration of front cylinder. In Case 1, by rotary oscillation of the front cylinder, depending on the reduced velocity and the spacing ratio values, the transverse oscillation amplitude of the rear cylinder suppresses, remains unchanged and even increases under certain conditions. Hence, at every spacing ratio and reduced velocity, an independent controller system for each cylinder is necessary to guarantee a perfect vibration reduction of front and rear cylinders.

The current manuscript seeks to deploy a type of active rotary oscillating (ARO) controller to attenuate the FIV of two tandem-arranged cylinders placed on elastic supports. Three different cases are considered so as to understand the interaction of these cylinders regarding the rotary oscillation.

This paper aims to propose a two-stage vibration isolation system for large airborne equipment to isolate aircraft vibration load.

First, the vibration isolation law of the discrete model of large airborne equipment under different damping ratios, stiffness ratios and mass ratios is analyzed, which guides the establishment of a three-dimensional solid model of large airborne equipment. Subsequently, the vibration isolation transfer efficiency is analyzed based on the three-dimensional model of the airborne equipment, and the angular and linear vibration responses of the two-stage vibration isolation system under different frequencies are studied.

Finally, studies have shown that the steady-state angular vibration at the non-resonant frequency changes little. In contrast, the maximum angular vibration at the resonance peak reaches 0.0033 rad, at least 20 times the response at the non-resonant frequency. The linear vibration at the resonant frequency is at least 2.14 times the response at the non-resonant frequency. Obviously, the amplification factor of linear vibration is less than that of angular vibration, and angular vibration has the most significant effect on the internal vibration of airborne equipment.

The two-stage vibration isolation equipment designed in this paper has a positive guiding significance for the vibration isolation design of large airborne equipment.

This paper aims to develop a robust controller to control vibration of a thin plate attached with two piezoelectric patches in the presence of uncertainties in the mass of the plate. The main goal of this study is to tackle dynamic perturbation that could lead to modelling error in flexible structures. The controller is designed to suppress first and second modal vibrations.

Out of various robust control strategies, μ-synthesis controller design algorithm has been used for active vibration control of a simply supported thin place excited and actuated using two piezoelectric patches. Parametric uncertainty in the system is taken into account so that the robust system will be achieved by maximizing the complex stability radius of the closed-loop system. Effectiveness of the designed controller is validated through robust stability and performance analysis.

Results obtained from numerical simulation indicate that implementation of the designed controller can effectively suppress the vibration of the system at the first and second modal frequencies by 98.5 and 88.4 per cent, respectively, despite the presence of structural uncertainties. The designed controller has also shown satisfactory results in terms of robustness and performance.

Although vibration control in designing any structural system has been an active topic for decades, Ordinary fixed controllers designed based on nominal parameters do not take into account the uncertainties present in and around the system and hence lose their effectiveness when subjected to uncertainties. This paper fulfills an identified need to design a robust control system that accommodates uncertainties.

Reducing noise and vibration is an increasingly important objective for designers and users of a wide range of mechanical systems. Lubricants can contribute to reduction of overall noise and vibration generated by machines, both by reducing generation of acoustic energy in lubricated contacts and by modulating the transmission of vibration through the lubricant. This paper outlines various mechanisms by which the lubricant may affect the generation and transmission of acoustic vibration. Examples from the area of refrigeration compressor lubrication are presented, demonstrating that correct design and selection of lubricant can have a significant impact on noise and vibration.

In this paper, improvements in reducing transmitted accelerations in a full vehicle are obtained by optimizing the gain parameters of an active control in a roughness road profile.

For a classically designed linear quadratic regulator (LQR) control, the vibration attenuation performance will depend on weighting matrices Q and R. A methodology is proposed in this work to determine the optimal elements of these matrices by using a genetic algorithm method to get enhanced controller performance. The active control is implemented in an eight degrees of freedom (8-DOF) vehicle suspension model, subjected to a standard ISO road profile. The control performance is compared against a controlled system with few Q and R parameters, an active system without optimized gain matrices, and an optimized passive system.

The control with 12 optimized parameters for Q and R provided the best vibration attenuation, reducing significantly the Root Mean Square (RMS) accelerations at the driver’s seat and car body.

The research has positive implications in a wide class of active control systems, especially those based on a LQR, which was verified by the multibody dynamic systems tested in the paper.

Better active control gains can be devised to improve performance in vibration attenuation.

The main contribution proposed in this work is the improvement of the Q and R parameters simultaneously, in a full 8-DOF vehicle model, which minimizes the driver’s seat acceleration and, at the same time, guarantees vehicle safety.

This paper aims to evaluate the dynamic response of surrounding foundation and study the vibration characteristics of track system.

A double-line underground coupling analysis model was established, which included two moving train, track, liner and the ground field.

Based on the 2.5D (D is diameter) finite element analysis, the influence of the important factors such as the depth of the subway tunnel, the nature of the foundation soil, the relative position relation of the double tunnel, the subway driving speed on the foundation and the orbital vibration are analyzed in this article.

The results in paper may have reference value for the prediction of train induced vibrations and for the research of dynamic response of ground field.

In order to investigate the vibration reduction properties of a three-dimensional elastic metastructure with spherical cavities at low frequencies.

The bandgap characteristics of a three-dimensional elastic metastructure with spherical cavities are studied based on analytical and numerical approaches.

The results of both method revealed that the vibration of the vertexes masses is important for opening bandgaps. The fact that the big sphere cavity radius or short side length of the cube unit leads to a wider bandgap, is noteworthy.

This research provides theoretical guidance for realizing the vibration attenuation application of EMs in practical engineering.

The main purpose of this paper is to investigate the vibration isolation performance of a quasi-zero stiffness (QZS) metastructure by employing the band gap (BG) mechanism.

The metastructure QZS characteristic was investigated through static analysis by numerical simulation. Based on that, the BG mechanism is primarily used in this article to investigate the wave propagation characteristics of this structure. The model's dispersion relation is then examined using theoretical (perturbation method) and finite element techniques. The dynamic response of the finite-size systems and experimental analysis is used to confirm the vibration mitigation property under investigation. Finally, the model's ability to absorb energy was examined and contrasted with a traditional model.

The analytical analysis reveals the dispersion curve and the effect of the nonlinear parameter on the curve shifting. The dispersion curve in the finite element method (FEM) result depicts five complete BGs within the range of 0–1,000 Hz, and the BG width accounted for 67.4% of the frequency concerned (0–1,000 Hz). Eigenmodes of the dispersion curves were analyzed to investigate the BG formation mechanisms. The dependence of BG opening and closure on structure parameters was also studied. Finally, the energy absorption property of the QZS metastructure was evaluated by comparing it with a classical model. The QZS structure absorbs 4.08 J/Kg compared to the 3.69 J/Kg absorbed by the classical model, which reveals that the QZS demonstrates better energy absorption performance. Based on the BG mechanism, it is clear that this model is an excellent vibration isolator, and the study reveals the frequencies at which complete vibration mitigation is achieved. As a result, this model could be a promising candidate for vibration mitigation engineering structures and energy absorption.

The tough vibration issue, which is primarily experienced in mechanical equipment, will be resolved in this study. This study provides a precise understanding of the QZS metastructure's isolation of vibration, including the frequencies at which this isolation occurs.