Vibrational Excitation Research Articles

Integrated design method for protection against vibration of offshore platform plate structure

The paper integrates the modal avoidance method, pedestal design method, and dynamic vibration absorber theory to investigate vibration control technology for offshore platform plate structures. We develop an integrated design method for vibration suppression by controlling the vibration excitation load, vibration transmission, and vibration energy dissipation. Firstly, a modal avoidance design is implemented to suppress vibration transmission along the propagation path of the plate structure. Subsequently, pedestal optimization is conducted for pedestal structure to attenuate vibration excitation at the input end. Finally, dynamic vibration absorber theory is employed to control dominant vibration frequency responses further and achieve multi-target vibration control. Case simulation results demonstrate that the integrated design method reduces the acceleration vibrations level at 113.75, 145.61, and 153 Hz, and this method could guide multi-objective vibration control in offshore platform plate structures.

Analysis of Scraper Conveyor Chain Dynamics under Falling Coal Impact Conditions

The scraper conveyor, essential for mechanized mining, operates in harsh underground environments and is subjected to severe impact loads from coal and rock falls. Such conditions can cause chain jamming, breakage, and other malfunctions, necessitating a detailed study of the system’s dynamic behavior under impact conditions. This study investigates the dynamic characteristics of a scraper conveyor’s chain drive system using a coupled ADAMS-EDEM simulation model. The model analyzes the effects of loaded coal piles on the conveyor’s dynamics during normal and impact conditions. Simulations show that loaded coal piles excite the scraper’s acceleration and sprocket rotation, with the greatest impact in the scraper’s running direction. Longitudinal impact and contact forces on the chain ring are more significant than in other directions under both no-load and loaded conditions. A strong linear relationship exists between the falling coal mass and longitudinal impact force. The coal pile causes prominent longitudinal vibration excitation while inhibiting the overall vibration of the chain drive system to some extent. The findings provide insights for identifying failure-prone areas under impact conditions and offer theoretical guidance for optimizing scraper conveyor design. This enhances mining efficiency and safety in coal operations.

Nonlinear characteristics and radial-bending-torsional vibration of a blade with breathing crack

Rotor failures due to cracked blades are frequently observed in rotating machinery. The identification of cracking state of rotating blade based on vibration characteristics has garnered a lot of attention. However, nonlinear characteristics and vibration combining in radial, bending and torsional directions of a rotating blade induced by the crack breathing is yet not clear. This paper proposes a radial-bending-torsional dynamic model of rotating blade with breathing crack. A time-varying integration method is proposed for determining the crack state based on the strain energy release rate. The crack breathing behavior is described by Boolean operation and the numerical integration are applied to open or close the crack. The model is validated through modal analysis, vibration responses and contact state of crack surface. Frequency veering is changed between the 2nd flap and 1st edgewise frequency due to the existence of crack. Strong nonlinear behaviors are found in the radial and torsional vibrations because of the crack breathing. Nonlinearities are also found in the combined vibrations between the radial-bending and the bending-torsional directions. Radial and torsional vibration amplitude levels can be used as an indication of blade crack failure, but the applicability depends on the absolute response decided by the aerodynamic excitation and resonant vibration. These findings can serve as guidance in crack identification and cracking state monitoring of rotating blades.

Quantum Calculation of the Vibrational Excitation of Nitrogen Molecules by Fast Ions: Can It Contribute to STEVE Formation?

AbstractThe vibrational‐translational (VT) excitation of nitrogen molecules led by collisions with fast ions in subauroral ion drifts (SAID) has been conceived as a potential underlying mechanism contributing to the formation of the Strong Thermal Emission Velocity Enhancement (STEVE) phenomenon (Harding et al., 2020, https://doi.org/10.1029/2020gl087102). In this study, we perform quantum calculations of the VT excitation rates of N2 led by fast‐drifting ions, and evaluate the resulting vibrational distribution of N2 with ionospheric/thermospheric parameters expected under intense SAID condition. We conclude that, while the VT energy transfer led by SAID plays a distinguishable role in the vibrational excitation of N2, it is incapable of populating the high vibrational levels to the required concentration (Harding et al., 2020, https://doi.org/10.1029/2020gl087102) to produce adequate nitric oxide density, and in turn the nitrogen‐dioxide continuum intensity, to account for the STEVE brightness.

Study on the Influence of Volute Throat Jet on Excitation Vibration Alleviation of Radial Turbine Blade

Abstract Turbine blade fracture, resulting from high-cycle fatigue (HCF), is the most commonly observed failure mode of turbochargers. In a vaneless turbine, the radial turbine blade is susceptible to HCF under excessive aerodynamic excitation due to the flow field distortion caused by the volute tongue. The present study explores a technique to mitigate blade excitation by reducing pressure disturbance in the volute tongue area. The gas with higher pressure in the inlet section of the volute is transferred to the low-static pressure area upstream of the volute tongue through a throat jet hole. The usage of high-pressure gas improved the homogeneity of the flow field near the volute tongue. The study investigates the mitigation of high-pressure gas jet on turbine blade excitation, the impact of jet hole geometry on the suppression effect of the blade vibration, and the effect of high-pressure jet on turbine performance using numerical simulation of unsteady flow fields. The results indicate that the jet flow has a substantial impact on dampening the blade vibrations. The harmonic pressure amplitude at the monitor point located within the high blade vibration amplitude region is reduced by up to 56%. Generalized pressure analysis reveals that the aerodynamic excitation of the turbine blades is significantly reduced. Experimental evidence verifies the effectiveness of the jet hole scheme in reducing blade vibration. Moreover, the jet hole has a negligible effect on turbine efficiency. However, there is a degree of increased stress in the volute tongue with a jet hole which needs to be evaluated in engineering applications.

Prediction of rail wear band evolution under excitation by periodic track irregularities and its influence on vehicle dynamic performance

Periodic track irregularities (PTIs) are an important and sensitive source of vehicle vibration and have attracted considerable attention from railway researchers. However, previous studies have mainly focused on the irregularities themselves, with limited investigation of how the rail wear band (RWB) generated by PTIs excitation affects vehicle responses. To assess this, a three-dimensional rail wear prediction model is developed in this study to simulate the evolution of the RWB under PTIs conditions and then the effect of RWB excitation on the vehicle dynamic performance is investigated. The results show that the spatial trace of the rail contact points generated by the PTIs also exhibits clear periodic characteristics. Accordingly, the distribution pattern of the RWB also reflects these periodic features. The excitation of the periodic rail wear band (PRWB) has a negative effect on the vehicle running stability, especially when the vehicle is traveling at speeds that induce coupling resonance, which exacerbates the consequences. As the wear level of the PRWB increases, there is also an escalation in the vibration of the carbody. Furthermore, the amplitude of the change in the wheelset balance position resulting from variations in rail profile is found to serve as an effective descriptor for characterizing the wear intensity of PRWB, and the vibration amplitude of the carbody exhibits a clear linear correlation with PRWB excitation. The research results are helpful for understanding the relationship between PRWB excitation and vehicle vibration behavior and serve as a theoretical basis for track maintenance and profile optimization.

Energy level spectrum and lattice polarization of polaron in metal halide perovskite parabolic quantum wells

In this study, polaron effect in 2D metal halide perovskite materials (TMHPMs), which naturally form quantum well (QW) structures, has been investigated. Polarization of carriers and lattice within these structures was explored based on unitary transformation and variational methods. Specifically, lattice polarization and energy level transition spectra of strong coupling polaron in parabolic potential metal halide perovskite QWs (MAPbCl3, MAPbBr3, and MAPbI3) were studied. Also, we calculated ground and first excited state energies, excitation energy, transition frequency, and vibration frequency of a TMHPM QWs. Our results indicated that parabolic potential confinement intensity affected related physical quantities, which provided insight to investigate metal halide perovskite materials and polaron effect.

Nonlinear interactions of an n-layer X-shape low-frequency vibration isolator equipped with a nonlinear vibration absorber at 1:1 internal resonance: analytical and numerical investigations

This work addresses, for the first time, the nonlinear dynamics of an n− layers bioinspired X− shape low-frequency vibration isolation system equipped with a nonlinear vibration absorber. The comprehensive mathematical model governing the two-degree-of-freedom system has been derived using Lagrangian mechanics. The method of averaging was applied to obtain an accurate analytical solution for the derived mathematical model. Utilizing the established analytical solution, the dynamical characteristics of the X− shape vibration isolator have been explored both as a single-degree-of-freedom system and after coupling with the proposed vibration absorber, as a two-degree-of-freedom system. The influence of different system parameters, including the number of structure layers, the initial inclination angle, the X− shape rod length, and the absorber stiffness and damping coefficients, on the vibration isolation performance has been investigated. The main findings indicate that while the single-degree-of-freedom X− shape low-frequency vibration isolator performs well in eliminating low-frequency vibration excitations, it exhibits strong vibration levels when the base excitation frequency exceeds the structure's natural frequency. Additionally, it was found that coupling a highly damped linear vibration absorber to the X− shape isolator not only eliminates the strong oscillations of the structure when subjected to high-frequency base excitations but also enhances the structure's low-frequency vibration isolation performance. Moreover, it was reported that integrating a nonlinear vibration absorber with either soft or hard spring characteristics instead of a linear one may degrade the vibration isolation performance of the structure rather than enhance it. Finally, numerical validation of all the analytical results was performed, which showed excellent correspondence with the analytical findings.

Mid-Infrared Photoacoustic Stimulation of Neurons through Vibrational Excitation in Polydimethylsiloxane.

Photoacoustic (PA) emitters are emerging ultrasound sources offering high spatial resolution and ease of miniaturization. Thus far, PA emitters rely on electronic transitions of absorbers embedded in an expansion matrix such as polydimethylsiloxane (PDMS). Here, it is shown that mid-infrared vibrational excitation of C─H bonds in a transparent PDMS film can lead to efficient mid-infrared photoacoustic conversion (MIPA). MIPA shows 37.5 times more efficient than the commonly used PA emitters based on carbon nanotubes embedded in PDMS. Successful neural stimulation through MIPA both in a wide field with a size up to a 100µm radius and in single-cell precision is achieved. Owing to the low heat conductivity of PDMS, less than a 0.5°C temperature increase is found on the surface of a PDMS film during successful neural stimulation, suggesting a non-thermal mechanism. MIPA emitters allow repetitive wide-field neural stimulation, opening up opportunities for high-throughput screening of mechano-sensitive ion channels and regulators.

Experimental studies of H2/Ar plasma in a cylindrical inductive discharge with an expansion region

Abstract The electrical parameters of H2/Ar plasma in a cylindrical inductive discharge with an expansion region are investigated by a Langmuir probe, where Ar fractions range from 0% to 100%. The influence of gas composition and pressure on electron density, the effective electron temperature and the electron energy probability functions (EEPFs) at different spatial positions are present. In driver region, with the introduction of a small amount of Ar at 0.3 Pa, there is a rapid increase in electron density accompanied by a decrease in the effective electron temperature. Additionally, the shape of the EEPF transitions from a three-temperature distribution to a bi-Maxwellian distribution due to an increase in electron–electron collision. However, this phenomenon resulting from the changes in gas composition vanishes at 5 Pa due to the prior depletion of energetic electrons caused by the increase in pressure during hydrogen discharge. The EEPFs for the total energy in expansion region is coincident to these in the driver region at 0.3 Pa, as do the patterns of electron density variation between these two regions for differing Ar fractions. At 5 Pa, as the discharge transitions from H2 to Ar, the EEPFs evolved from a bi-Maxwellian distribution with pronounced low energy electrons to a Maxwellian distribution in expansion region. This evolve may be attributed to a reduction in molecular vibrational excitation reactions of electrons during transport and the transition from localized electron dynamics in hydrogen discharge to non-localized electron dynamics in argon discharge. In order to validate the experimental results, we use the COMSOL simulation software to calculate electrical parameters under the same conditions. The evolution and spatial distribution of the electrical parameters of the simulation results agree well with the trend of the experimental results.

Electric Calibration for Heterodyne Laser-Doppler Vibrometers at High Frequency

Abstract Calibration for Heterodyne Laser-Doppler Vibrometers (HLDV) is important for its accuracy and reliability. ISO 166063-41 provides primary and secondary calibration specifications for HLDV only in the frequency range from 0.4Hz to 50kHz, which can’t meet current demand for higher frequency. To be specific, the vibration exciter limits calibration frequency to a higher range. With this in mind, the electric calibration is presented. As a substitution method, the high precision arbitrary waveform generator replaces the optical module to output synthesized Doppler heterodyne signals which can cover all the required frequency. In addition, a commercial demodulator is used for calibration in the frequency range up to 1MHz. By theoretical introduction and experimental verification, this method offers significant improvement and thus potential over existing methods for HLDV calibration.

Dynamics of the Cl + CH3CN reaction on an automatically-developed full-dimensional abinitio potential energy surface.

A full-dimensional analytical potential energy surface (PES) is developed for the Cl + CH3CN reaction following our previous work on the benchmark abinitio characterization of the stationary points. The spin-orbit-corrected PES is constructed using the Robosurfer program and a fifth-order permutationally invariant polynomial method for fitting the high-accuracy energy points determined by a ManyHF-based coupled-cluster/triple-zeta-quality composite method. Quasi-classical trajectory simulations are performed at six collision energies between 10 and 60kcal mol-1. Multiple low-probability product channels are found, including isomerization to isonitrile (CH3NC), but out of the eight possible channels, only the H-abstraction has significant reaction probability; thus, detailed dynamics studies are carried out only for this reaction. The cross sections and opacity functions show that the probability of the H-abstraction reaction increases with increasing collision energy (Ecoll). Scattering angle, initial attack angle, and product relative translational energy distributions indicate that the mechanism changes with the collision energy from indirect/rebound to direct stripping. The distribution of initial attack angles shows a clear preference for methyl group attack but with different angles at different Ecoll values. Post-reaction energy distributions show that the energy transfer is biased toward the products' relative translational energy instead of their internal energy. Rotational and vibrational energy have about the same amount of contribution to the internal energy in the case of both products (HCl and CH2CN), i.e., both of them are formed with high rotational excitations. HCl is produced mostly in the ground vibrational state, while a notable fraction of CH2CN is formed with vibrational excitation.

Hydration structure and dynamics of phosphoric acid and its anions-Ultrafast 2D-IR spectroscopy and abinitio molecular dynamics simulations.

The hydration shells of phosphate ions and phosphate groups of nucleotides and phospholipid membranes display markedly different structures and hydrogen-bond strengths. Understanding phosphate hydration requires insight into the spatial arrangements of water molecules around phosphates and in thermally activated structure fluctuations on ultrafast time scales. Femtosecond two-dimensional infrared spectroscopy of phosphate vibrations, particularly asymmetric stretching vibrations between 1000 and 1200cm-1, and abinitio molecular dynamics (AIMD) simulations are combined to map and characterize dynamic local hydration structures and phosphate-water interactions. Phosphoric acid H3PO4 and its anions H2PO4-, HPO42-, and PO43- are studied in aqueous environments of different pH value. The hydration shells of phosphates providing OH donor groups in hydrogen bonds with the first water layer undergo ultrafast structural fluctuations, which induce a pronounced spectral diffusion of vibrational excitations on a sub-300fs time scale. With a decreasing number of phosphate OH groups, the hydration shell becomes more ordered and rigid. The 2D-IR line shapes observed with hydrated PO43- ions display a pronounced inhomogeneous broadening, reflecting a distribution of hydration geometries without fast equilibration. The AIMD simulations allow for an in-depth characterization of the hydration geometries with different numbers of water molecules in the first hydration layer and different correlation functions of the fluctuating electric field that the water environment exerts on the vibrational phosphate oscillators.

Dynamic and Phase-Frequency Characteristics of Rotor Instability Induced by Steam Flow Excited Vibration in Seals

Steam flow excited vibration in seals seriously affects the seal-rotor stability. A mesh deformation based on user-defined functions was adopted to establish the multi-frequency whirl model, and the reliability of the simulation method was verified by experiments. The average effective damping and working ability of the fluid were proposed to analyse the stability of the seal. The mechanism of seal instability induced by steam flow excited vibration was revealed through the phase-frequency characteristics of exciting forces and displacements. The results show that direct damping decreases gradually with an increase in frequency, and the cross-coupling damping tends to be stable over 15 Hz. The average effective damping is more sensitive and accurate in predicting the seal stability. Effective damping decreases with increased frequency. Therefore, the rotor stability is decreased. Near the 12 Hz and 24 Hz frequencies, the average effective damping of eccentricity fluctuates, so the seal stability is poor. The negative effect of exciting forces increases, and the seal stability is improved when the eccentricity increases. When the phase difference between the excitation force and displacement changes, the seal stability decreases. The fundamental reason for rotor instability induced by steam flow excited vibration in seals is the sharp changes of phase difference caused by pressure fluctuations.

Influence of the Initial Prestress Level on the Distribution of Regions of Dynamic Instability of Geiger Domes

This paper provides a parametric analysis of cable–strut tensegrity domes subjected to periodic loads. This analysis aims at determining the main regions of dynamic instability (unstable regions). From the point of view of the physical interpretation of the phenomenon, if the load occurs in these regions, the amplitudes of the resulting vibrations increase, posing a risk to the durability of the structures. The consideration includes cable–strut structures called Geiger domes. Four dome design solutions known from the literature are compared, i.e., regular (patented by Geiger) and modified domes with a closed and an open upper section. In contrast to conventional cable–strut structures, Geiger domes are characterized by a self-equilibrated system of internal forces (initial prestress), which affects the shape and range of unstable regions. The main purpose is to answer the question as to which type of design solution is more sensitive to the risk of excitation vibrations. A nondimensional parameter λ is introduced for this quantitative assessment. This parameter reliably determines the change in the area of unstable regions as the initial prestress level increases. The range of the parameter λ is defined as a value between 1 and 0. In the case of λ=1, there is potential for the excitation of unstable motion, whereas in the case of λ=0, such a risk is absent. The analysis presented in this paper can be employed in the process of optimizing the initial prestress level, which will constitute the subsequent stage of this research. A geometrically non-linear model is used to evaluate the behavior of the considered structures.

Energy and spectroscopic parameters of neutral and cations isomers of the CnH2 (n = 2-6) families using high-level ab-initio approaches.

Cationic species, previously detected from ion-induced desorption of solid methane by plasma desorption mass spectrometry (PDMS), and neutral species, are investigated using high-level ab-initio approaches. From a set of 25 cationic and 26 neutral structures belonging to CnH2 (n = 2-6) families, it was obtained the energy, rotational constants, harmonic vibrational frequency, charge distribution and excitation energies. The ZPVE-corrected energies, at CCSD(T)-F12; CCSD(T)-F12/RI/(cc-pVTZ-F12, cc-pVTZ-F12-CABS, cc-pVQZ/C) (n = 2-5) and CCSD(T)/cc-pVTZ (n = 6) levels, reveal that the topology of the most stable isomer vary with n and the charge. Out of 674 harmonic frequencies, those with maximum intensity are generally in the 3000-3500 cm-1 range. Analysis of 169 vertical transition energies calculated with the EOM-CCSD approach, suggest three C6H2 species as potential carriers of the diffuse interstellar bands (DIB). Systematic comparison of properties between neutral and cationic species can assist in the structural description of complex matrices.

Molecular Hydrogen Formation via Vibrational Excitation of Partially Superhydrogenated Pyrenes

While polycyclic aromatic hydrocarbons (PAHs) are now accepted to be abundant in interstellar space, the abundance and influence of superhydrogenated PAHs (HPAHs) in the interstellar medium (ISM) are still under investigation. HPAHs may act as catalysts for or reactants in small-molecule formation via hydrogen abstraction reactions, H2 evaporation, and carbon skeleton fragmentation. Here, we present a gas-phase infrared (IR) action spectroscopy study of the HPAH 4, 5, 9, 10-tetrahydropyrene (THP; C16H14), performed at the Free Electron Lasers for Infrared eXperiments facility. IR action spectroscopy was performed on the THP cation, protonated THP, and their fragments produced by collision-induced dissociation in the range from 600 to 1800 cm−1. Calculated IR spectra, at the density functional theory level, agree with experimental IR spectra to a high degree and were utilized to determine molecular structures of the HPAH fragments. Molecular dynamics simulations compared with experimental mass spectra reveal favorable HPAH fragmentation pathways. Molecular hydrogen (H2) is observed to be a primary fragment of [THP+H]+ with superhydrogenated duo groups. This contrasts the notion that HPAHs typically undergo carbon skeleton fragmentation leading to C x H y formation. These observations show that lowered symmetry and duo or trio aliphatic groups on HPAHs uniquely change their IR spectra, stability, and fragmentation patterns. As a result, these species may contribute to H2 formation in the ISM.

Statistical analysis of technical specifications for non-reversible plate vibrators with different types of engines

Introduction. Forward plate compactors are surface soil compaction machines with a flat operating device, which are usually equipped with a single-shaft vibration exciter. Forward plate compactors may be driven by gasoline, diesel or electric engines. When designing and modernizing forward plate compactors, a problem of technical specifications justification may arise, including such parameters as exciting force, vibration exciter oscillation frequency, engine power, base plate width, etc. This statistical analysis of plate compactors with different types of engines was carried out to summarize manufacturers practices and reveal correlations between the technical specifications of forward plate compactors.Materials and methods. This research is based on the information presented on the official websites of forward plate compactors manufacturers and their dealers. 644 models of forward plate compactors were scrutinized. Regression equations and correlation coefficients were derived using Microsoft Excel software.Results. Parameters ranges for forward plate compactors with different types of engines were determined. Regression equations of correlations between oscillation frequency, exciting force, engine power, base plate width, relative exciting force and mass of forward plate compactors with different types of engines were derived, as well as the corresponding correlation coefficients. It was revealed, that most parameters have low or very low correlation coefficient, regardless of the engine type.Conclusion. The ranges of the technical specifications of diesel and gasoline forward plate compactors are quite close to each other. The parameters ranges of electric plate compactors, in most cases, are beyond the ranges of gasoline and diesel plate compactors. Low correlation coefficients and a large scatter of parameters indicate that manufacturers do not have a methodology for justification of the technical specifications of forward plate compactors. Results of the study may be used when clarify ranges of parameters and formulate requirements for a mathematical model of vibration plates behavior.

The effects of acoustic disturbances and mechanical vibration on laminar premixed flames: A comparative study

The energy conversion between the combustion process and acoustic waves is very complex in high-performance propulsion systems, which may trigger large-amplitude combustion instabilities, potentially leading to severe vibration or structural damage. Both acoustic disturbances and mechanical vibration are found to be able to cause the combustion instability, but their differences on the influence of laminar premixed flames are still unknown. In this paper, a premixed methane flame burner was disturbed by either a loudspeaker or an electromagnetic vibration exciter, and the effects of their forcing frequencies and amplitudes on the dynamic responses of the premixed methane flame were evaluated. Specifically, the unsteady heat release rate was measured by a photomultiplier tube, and the flame dynamic behaviors were captured by a high-speed camera with image intensifier. Furthermore, the acoustic disturbances upstream of the flame was measured by the two-microphone method, and the structure vibration was measured by an accelerometer. Then, the flame transfer functions were obtained at various equivalence ratios and mean flow velocities. The results demonstrated that the premixed flame exhibited obvious band-pass filtering characteristics when subjected to external forcing, whether through a loudspeaker or an electromagnetic vibration exciter. In addition, increasing either acoustic or structure excitation amplitude to a large extent can make the flame respond in a nonlinear manner. However, when the flame was subjected to mechanical vibration, the peak frequency corresponding to the maximum gain of the flame transfer function had minimal sensitivity to variations in equivalence ratios and mean flow velocities. In contrast, the acoustic disturbances were more likely to induce the nonlinear flame responses and flame front wrinkling.

Low-Cost and Paper-Based Micro-Electromechanical Systems Sensor for the Vibration Monitoring of Shield Cutters.

Vibration sensors are widely used in many fields like industry, agriculture, military, medicine, environment, etc. However, due to the speedy upgrading, most sensors composed of rigid or even toxic materials cause pollution to the environment and give rise to an increased amount of electronic waste. To meet the requirement of green electronics, biodegradable materials are advocated to be used to develop vibration sensors. Herein, a vibration sensor is reported based on a strategy of pencil-drawing graphite on paper. Specifically, a repeated pencil-drawing process is carried out on paper with a zigzag-shaped framework and parallel microgrooves, to form a graphite coating, thus serving as a functional conductive layer for electromechanical signal conversion. To enhance the sensor's sensitivity to vibration, a mass is loaded in the center of the paper, so that higher oscillation amplitude could happen under vibrational excitation. In so doing, the paper-based sensor can respond to vibrations with a wide frequency range from 5 Hz to 1 kHz, and vibrations with a maximum acceleration of 10 g. The results demonstrate that the sensor can not only be utilized for monitoring vibrations generated by the knuckle-knocking of plastic plates or objects falling down but also can be used to detect vibration in areas such as the shield cut head to assess the working conditions of machinery. The paper-based MEMS vibration sensor exhibits merits like easy fabrication, low cost, and being environmentally friendly, which indicates its great application potential in vibration monitoring fields.