Structural vibrations could seriously affect the working performance and even cause fatal hazards to host structures. To reduce low frequency vibrations, a locally resonant metamaterial beam coupled by horizontal springs is proposed. The dynamic model of the metamaterial beam is established with the finite element method. The frequency response function of the metamaterial beam is derived, and the

The transfer matrix method for multibody system takes into account the accuracy of the equations of motion and the efficiency of the algorithm. Especially if a system is composed of flexible and rigid components, transfer matrix method for multibody system reduces the dynamics problem to an overall transfer equation which only involves boundary state vectors. The state vectors at the boundary are made

In this article, the coupling effects of the unbalanced magnetic pull and ball bearing on nonlinear vibration of the three-phase asynchronous motor are investigated with the experimental and numerical methods. A test rig of a motor whose rotor supported by ball bearings is used and a 2 degrees of freedom magnetic solid coupling dynamic model of the motor rotor system is presented. The nonlinear dynamic

In this article, an innovative technique to design a robust finite-time state feedback controller for a class of uncertain robotic manipulators is proposed. This controller aims to converge the state variables of the system to a small bound around the origin in a finite time. The main innovation of this article is transforming the model of an uncertain robotic manipulator into a new time-varying form

This article investigates the influence of graphene platelet reinforcements and nonlinear elastic foundations on geometrically nonlinear dynamic response of a partially fluid-filled functionally graded porous cylindrical shell under exponential loading. Material properties are assumed to be varied continuously in the thickness in terms of porosity and graphene platelet reinforcement. In this study

In a feedback control loop, when there exists a delay in processing the control signal (often called computational delay), it is difficult to stabilize the system, particularly when the system exhibits uncertainty. To solve this problem, we proposed a new robust proportional integral control strategy for a class of uncertain systems exhibiting parametric uncertainty. A two-stage scheme is proposed

In this article, bistable laminates are statically and dynamically studied under the existence of nonlinear magnetic force. The bistable laminates with magnetic forces are considered as a nonlinear system for vibration energy harvesting. First, a semi-analytical model was established based on the energy approach for the bistable plate together with magnets. The magnetic force versus distance was measured

To study the correlation between noise and vibration during dry milling of aluminum alloy, a synchronous acquisition system of noise and vibration was established. Based on the experimental data, the effects of three milling parameters on milling noise and milling vibration were analyzed. Based on the least square method and MATLAB software programming, the multiple regression models of milling noise

Because of the nonlinear factors in the standard vibrators, the output waveform of the vibrators is usually distorted, especially in the low-frequency band. Traditionally, the harmonic distortion is suppressed by improved design of the vibrator and feedback control. However, these approaches can just suppress the harmonics to some extent. There are still residual harmonic components which cannot be

Permanent magnet synchronous motor always suffers from air gap field distortion and inverter nonlinearity, which lead to the harmonic components in motor currents. A resonant controller is a remarkable control method to eliminate periodic disturbance, whereas the conventional resonant controller is limited by narrow bandwidth and phase lag. This article presents a novel resonant controller with a precise

Dispersion equation is derived for the propagation of one-dimensional plane waves in a general linear anisotropic isothermal elastic–plastic material with voids. The plasticity of the considered material is defined through the dislocation of a single slip plane and direction. The derived dispersion equation is then reduced for the relevant wave propagation in particular media, namely, monoclinic, orthotropic

A new type of the acoustic black hole beam—a helix-acoustic black hole—is proposed to overcome the spatial restriction on modular acoustic black hole structures. The modular acoustic black hole structure, consisted of a base and several number of acoustic black hole beams, has potential to apply into real engineering world. There are two main sections in an acoustic black hole beam: (1) a uniform thickness

As a hollow cylindrical structure, a nanotube has potential to convey nanoflow, which has opened up a field of research. Functionally graded nanotube as a designable structure with continuous variation of material properties can perform better than uniform nanotube, especially in physical field without introducing large stress concentration. In this article, we take the thermal effect into account

When cracks start to surface in the surrounding areas of the structure, they create a local softness zone and influences on the dynamic response of the structure. The beams are more susceptible to shear and flexural cracks because of being subjected to shear and bending stress. In this study, the dynamic response of the single-span and multi-span damped beam under moving load with multi-crack and elastic

Research indicates that single-walled carbon nanotubes have a unique coupled torsional–radial vibration as one of their fundamental modes. Determination of their vibration frequency is required for efficient use of single-walled carbon nanotube in nano-electromechanical systems. However, there is no mathematical expression for these frequencies and their dependence on single-walled carbon nanotube

The dynamic response of the host structure to a high-frequency actuation is usually used for the detection of tiny damage in structures in the form of breathing crack. The simulation of the microcrack’s effect on the response is essential for several damage identification targets. The conventional finite element method suffers from very small mesh size requirements to address the high-frequency problems

One of the problems associated with vibration pollution is ground vibration. In view of the isolation of objects protected from ground-transmitted vibrations, a novel type of vibration isolation barrier, an open trench–wave impedance block, is proposed. Based on the perfectly matched layer absorbing boundary, the two-dimensional finite element method in the frequency domain is used to investigate the

A novel optimization technique was implemented to investigate the effects of vibrations on comfort of occupants to maintain oscillations in an acceptable zone in accordance with the International Organization for Standardization 2631 standard. In this regard, a newly introduced comfort indicator was defined as discomfort criterion (DiC). The effectiveness of the proposed measure was investigated throughout

Complex disturbances with multifrequency components inevitably exist in the attitude control system of flexible spacecrafts. Multirate iterative learning disturbance observer (MILDO) is a promising solution to estimate and attenuate these disturbances much more accurately. However, measurement delay in the attitude measurement system may severely degrade the estimation performance of MILDO and even

The self-excited vibration of flexible planar 3-RRR parallel manipulators is converted from the residual vibration after high-speed motion and is a resonance of the strongly coupled and nonlinear electromechanical system. This makes the active vibration control quite a challenging task. In this study, we attempt to adopt the radial basis function neural network control algorithm based on acceleration

The static and dynamic pull-in phenomenon of a functionally graded Al/Al2O3 microplate, considering the damping coefficient and fringing field effects, has been analyzed because of its crucial effect in micro-electromechanical systems application, especially in microswitches. The nonlinear equation of motion of functionally graded microplate has been derived using Hamilton’s principle, and solved analytically

To enhance the low-frequency broadband sound absorption, we propose an absorber filled with porous material and establish a relative acoustic model. Based on the critical coupling condition, a Helmholtz absorber was designed to achieve perfect sound absorption at 172 Hz by the complex frequency plane method. Considering the weak adjustability and acoustic impedance of the Helmholtz absorber, we devised

This research work aims to investigate the presence of four nonlinear characteristics (i.e., hysteresis, saturation, creep, and uncertainty vibration) when a piezoelectric patch material acts as an actuator and sensor for the active vibration suppression of a cantilever beam. The parameters such as different operating frequencies and voltages are taken into account for the piezoelectric patch material

Smart structure vibration reduction based on adaptive active vibration control has become a hot research spot in recent years. A filtered-U least mean square algorithm based on an infinite impulse response filter structure is used to solve the interference of controller output to reference signal. The filtered-U least mean square algorithm is very suitable for the nonlinear vibration control of the

Numerous applications have been found in various microelectromechanical systems for shape memory alloys. This study analyzes the nonlinear free vibrations of a sandwiched microbeam, consisting of a shape memory alloy core and two elastic layers on either side. The behavior of the shape memory layer is modeled with the one-dimensional Brinson model. The equation of motion is derived from Hamilton’s

In this article, an adaptive neural network control system is proposed for a quarter car electrohydraulic active suspension system coping with dynamic nonlinearities and uncertainties. The proposed control system is primarily designed to stabilize a sprung mass position of the quarter car electrohydraulic active suspension. Linear controllers such as the proportional–integral–differential controller

Dynamic oscillating behavior of the flexible structure immerged in viscous fluids has attracted growing attention and been widely used in various practical applications. A general electricity-structure-fluid coupled model for the forced dynamic responses of a cantilever immersed in fluids, with partially distributed macro fiber composite, is proposed in this paper. Based on the classical Euler–Bernoulli

In this study, a distributed control problem is addressed for switched affine multi-agent systems. In dynamical systems with an affine control input, the use of error feedback is essential for the realization of consensus protocols, but different from most existing results with affine control multi-agent systems, switched affine multi-agent systems face additional difficulties in the analysis and control;

This study develops an efficient numerical method for optimal control problems governed by fractional Volterra integro-differential equations. A new type of polynomials orthogonal with respect to a discrete norm, namely discrete Hahn polynomials, is introduced and its properties investigated. Fractional operational matrices for the orthogonal polynomials are also derived. A direct numerical algorithm

This study focuses on the vibro-acoustic characteristics of submerged structures with concentrated elements and filled with fluid. A weak formulation is developed based on the modified variational principle. The accurate energy expressions for both structural and acoustic domains are incorporated into the coupled vibro-acoustic model. With introduced Lagrangian multipliers, a domain partitioning technique

In this article, a novel vibration control scheme of suspension systems is proposed. It combines the advantages of quasi-zero stiffness isolator, nonlinear energy sink absorber, and inerter. This proposed scheme can achieve low transmissibility, low amplitude, and low additional weight and resolve the conflict between riding comfort and handling stability. Strong nonlinear vibration equations of a

Smart sandwich cantilevers with aluminum faces and single and double cores, formed by assembled shear-mode piezoceramic patches with same poling, are experimentally and numerically assessed for the first time. To measure the electromechanical coupling efficiency of such vibrating smart structures, the so-called modal effective electromechanical coupling coefficient is used as a performance indicator

A new fractional-order Dickson functions are introduced for solving numerically fractional optimal control and variational problems involving Mittag–Leffler nonsingular kernel. The type of fractional derivative in the proposed problems is the Atangana–Baleanu–Caputo fractional derivative. In the process of the method, we use fractional-order Dickson functions and their properties to provide an accurate

The study shows a new nonlinear model of a rotating cantilever beam with tip mass. The nonlinear model is built with considering axial geometric nonlinear and large curvature. On the basis of the nonlinear Green strain–displacement relations, the nonlinear motion equations are derived using the Hamilton principle. Applying the proposed dynamic model, the effect of various parameters on the natural

In this study, based on parametric excitation originating from airflow oscillation, a novel nonlinear aeroelastic energy harvester is proposed. In this respect, first, the governing equation of the system is derived and studied thoroughly to understand the direct and indirect effects of airflow oscillation on the local and global responses of the system. Then, by using a pseudo-arclength continuation

The lateral position control of the vehicle is analyzed in the presence of time delay. To compensate the negative effects of dead time, the predictor control approach called finite spectrum assignment is applied. This controller includes a linear model of the plant and uses the solution of this model over the delay interval to predict the current system states. The focus of the article is whether to

Relative vibration between the cutter and workpiece has an influence on the surface generation and dimensional accuracy. In the present work, prediction models were developed for roundness and surface roughness of hole in terms of amplitude and frequency of tool vibration. The proposed methodology carried out a theoretical investigation on the effect of tool vibration components in X- and Y-directions

A two-axis gimbaled stabilization system in air vehicles must stabilize the line of sight of the payload toward a target against the external motion induced by air vehicle maneuvering and aerodynamic forces. The target tracking and pointing performances of the air vehicles are largely affected by air vehicle motion decoupling capability. In this work, the H∞ controller design is carried out for a two-axis

This study studies the performance of an integral force feedback controller for increasing the damping of lightweight flexible structures. Both methods of maximum damping and H∞ optimization are used to tune the parameters of the control system. Two modifications of the integral force feedback are proposed to compensate the effects of a soft stiffness to increase the authority of the actuator. Higher

To meet the demands of white noise waves with different and higher energy spectral density, a new white noise wave generation method was proposed and a corresponding wave-making system controlled by a rotary valve was developed. The theoretical model of the new method was established, and the hydraulic transmission function of the wave-making system was solved. After the control parameters of the white

This study deals with the vibration reduction of a cantilever beam using air-jet thruster actuators controlled by the particle swarm optimized quasi bang–bang controller. In this study, the finite element model of a cantilever beam with the lumped mass of actuators is formed for the numerical simulations. Furthermore, the first-order plus dead time transfer function of the air-jet thruster actuator

In this study, an approximation method with an integral operational matrix based on the Muntz wavelets basis is presented to solve the variational problems of moving or fixed boundary conditions and a computational algorithm is given for the suggested approach. First, the integral operational matrix is created through the Muntz wavelets. Then, by using this integral operational matrix with Lagrange

Vibration response and band gap characteristics of the functionally graded frame structures are investigated based on the first-order shear deformation theory. The material properties of functionally graded material rods vary continuously in thickness direction according to a power law. Spectral stiffness matrix of the periodic functionally graded material frame structure in the global coordinate system

Improper selection of cutting parameters leads to regenerative chatter and loss in productivity. In the present work, a methodology has been proposed to select a proper combination of input cutting parameters for stable turning with improved metal removal rate. Chatter signals generated during the turning of Al6061-T6 have been acquired using a microphone. Stability lobes diagram has been plotted to

In this study, the chaotic behavior of a viscoelastic plate under integrated non-Gaussian additive and multiplicative bounded noise is investigated with an analytical approach. First, the governing equation of motion of the system was derived by introducing a set of dimensionless parameters. After that, the modified version of Melinkov’s function in terms of statistical indices was obtained, and then

The use of robots has been rapidly spreading in different daily applications. The transport of liquids by robot arms without causing any slosh is one of such applications which has recently taken the attention of researchers. Liquid transfer by dual-arm robots causes challenging problems because, in the process of dual-arm cooperation, a closed kinematic chain is formed and a set of constraints appears

In this study, free vibration and buckling behaviors of a functionally graded nanoplate supported by the Winkler–Pasternak foundation using a nonlocal classical plate theory are investigated. Eringen’s nonlocal differential model has been used for considering the small-scale effect. The properties of the functionally graded nanoplate are considered to vary transversely following the power law. The

This study proposes a continuous convolution method combined with memoryless nonlinear transformation for multi-input multi-output stationary non-Gaussian random vibration tests. The challenge of the multi-shaker non-Gaussian random vibration test lies in the coupling problems that are manifested in the inherent physical system and in the existence of cross-spectral densities. In the presented method

The free vibration of orthotropic rectangular thin plates with four free edges on two-parameter elastic foundations is studied by the symplectic superposition method. Firstly, by analyzing the boundary conditions, the original vibration problem is converted into two sub-vibration problems of the plates slidingly clamped at two opposite edges. Based on slidingly clamped at two opposite edges, the fundamental

When a wheel rolls over a railway rail, it ‘sees’ a varying stiffness downwards because the rail is periodically supported by sleepers, leading to parametric excitation of the rail/wheel system. This study investigates the importance of parametric excitation on railway noise generation. Because the problem is non-stationary, it is modelled in the time domain. Rail and wheel impulse response functions

Tremor is an involuntary movement that makes many patients suffer, and passive absorbers used in wearable robot are proved to be effective for tremor suppression. A particle damper is a kind of a passive vibration control device taking advantage of energy dissipation and momentum exchange caused by particle collisions. To apply particle damping technology in reducing tremor amplitude in the human hand

After detecting initial delamination damage in a hotspot region of a composite structure monitored through a data-driven approach, the user needs to decide if there is an imminent structural failure or if the system can be kept in operation under monitoring to track the damage progression and its impact on the structural safety condition. Therefore, this study proposes delamination area quantification

Experimental results show that mechanical behaviors of viscoelastic dampers are greatly affected by ambient temperature. Neglecting the ambient temperature effect will lead to an inaccurate seismic evaluation on viscoelastically damped structures. This study investigates the ambient temperature effect on the seismic performance of viscoelastically damped structures. An efficient algorithm is proposed

One of the performance-limiting factors in the design of robust controllers for active magnetic bearing systems is the fact that the controller needs to be robust to the gyroscopic effects, that is rotational speed-dependent dynamics of the system. Studies in the literature show that better performance and stability can be achieved when gyroscopic effects are explicitly handled by a cross-feedback

In this study, a robust adaptive controller is designed to be used in an active tuned mass damper system that can be used to damp undesired vibrations that occurred on the multistory buildings during the earthquake. To realize the controller design, all of the system parameters are assumed to be unknown, and the adaptive structure of the designed controller is obtained by designing adaptive compensation

In crane systems, lifting, carrying and lowering the load from one place have different dynamic effects on the system. One of these dynamic effects is the moving load problem caused by the movement of the load on the crane system. With the increasing technology in recent years, production speeds have increased. For this reason, it has made the requirements for fast-running cranes mandatory for the

A mathematical discussion is introduced to describe the receiver coil characterizing a nuclear magnetic resonance for imaging, starting from a general shape of the conductor. A set of different inductance calculations have been introduced, varying the shape of the conductor. The inductance calculation led to a general expression of the magnetic field of a single coil characterized by a rectangular

Natural frequency and damping behavior of three-layer cylindrical shells with a viscoelastic core layer and functionally graded face layers are studied in this article. Using functionally graded face layers can reduce the stress discontinuity in the face–core interface that causes a catastrophic failure in sandwich structures. The viscoelastic layer is expressed using a fractional-order model, and

Position controllers are used for free motion, whereas force controllers are used for constrained motion of robotic manipulators. The hybrid controller switches between position and force control modes depending on whether the manipulator is in contact with the environment. To improve production efficiency, the velocity of contact between the manipulator and environment is not set to zero. However

In the monitoring of structural systems, the use of multiple high-end sensors may prove to be economically prohibitive. The alternative approach would be to use fewer devices capable of moving across the span of the structural system. In the proposed approach, a velocity sensor that is able to move across the spatial domain and obtain point-wise velocity measurements is combined to a novel dynamic