Low-frequency Applications Research Articles

Very low frequency IEPE accelerometer calibration and application to a wind energy structure

Abstract. In this work, we present an experimental setup for very low frequency calibration measurements of low-noise integrated electronics piezoelectric (IEPE) accelerometers and a customised signal conditioner design for using IEPE sensors down to 0.05 Hz. AC-response IEPE accelerometers and signal conditioners have amplitude and phase deviations at low frequencies. As the standard calibration procedure in the low-frequency range is technically challenging, IEPE accelerometers with standard signal conditioners are usually used in frequency ranges above 1 Hz. Vibrations on structures with low eigenfrequencies like wind turbines are thus often monitored using DC-coupled micro-electro-mechanical system (MEMS) capacitive accelerometers. This sensor type suffers from higher noise levels compared to IEPE sensors. To apply IEPE sensors instead of MEMS sensors, in this work the calibration of the entire measurement chain of three different IEPE sensors with the customised signal conditioner is performed with a low-frequency centrifuge. The IEPE sensors are modelled using infinite impulse response (IIR) filters to apply the calibration to time-domain measurement data of a wind turbine support structure. This procedure enables an amplitude and phase-accurate vibration analysis with IEPE sensors in the low-frequency range down to 0.05 Hz.

Handcycling with concurrent lower body low-frequency electromyostimulation significantly increases acute oxygen uptake: implications for rehabilitation and prevention.

BackgroundAcute increases in exercise-induced oxygen uptake (V̇O2) is crucial for aerobic training adaptations and depends on how much muscle mass is involved during exercising. Thus, handcycling is per se limited for higher maximal oxygen uptakes (V̇O2max) due to restricted muscle involvement. Handcycling with additional and simultaneous application of low-frequency electromyostimulation (EMS) to the lower extremities might be a promising stimulus to improve aerobic capacity in disabled and rehabilitative populations.MethodTwenty-six healthy young adults (13 female, age: 23.4 ± 4.5 years, height: 1.77 ± 0.09 m, mass: 71.7 ± 16.7 kg) completed 4 ×10 minutes of sitting (SIT), sitting with concurrent EMS (EMS_SIT), handcycling (60 rpm, 1/2 bodyweight as resistance in watts) (HANDCYCLE) and handcycling with concurrent EMS of the lower extremities (EMS_HANDCYCLE). During EMS_SIT and EMS_HANDCYCLE, low frequency EMS (impulse frequency: 4Hz, impulse width: 350 µs, continuous stimulation) was applied to gluteal, quadriceps and calf muscles. The stimulation intensity was selected so that the perceived pain could be sustained for a duration of 10 minutes (gluteus: 80.0 ± 22.7 mA, quadriceps: 94.5 ± 20.5 mA, calves: 77.5 ± 19.1 mA).ResultsSignificant mode-dependent changes of V̇O2 were found (p < 0.001, ηp2 = 0.852). Subsequent post-hoc testing indicated significant difference between SIT vs. EMS_SIT (4.70 ± 0.75 vs. 10.61 ± 4.28 ml min−1 kg−1, p < 0.001), EMS_SIT vs. HANDCYCLE (10.61 ± 4.28 vs. 13.52 ± 1.40 ml min−1 kg−1, p = 0.005), and between HANDCYCLE vs. EMS_HANDCYCLE (13.52 ± 1.40 vs. 18.98 ± 4.89 ml min−1 kg−1, p = 0.001).ConclusionHandcycling with simultaneous lower body low-frequency EMS application elicits notably higher oxygen uptake during rest and moderately loaded handcycling and may serve as an additional cardiocirculatory training stimuli for improvements in aerobic capacity in wheelchair and rehabilitation settings.

A Review on SIW and Its Applications to Microwave Components

Substrate-integrated waveguide (SIW) is a modern day (21st century) transmission line that has recently been developed. This technology has introduced new possibilities to the design of efficient circuits and components operating in the radio frequency (RF) and microwave frequency spectrum. Microstrip components are very good for low frequency applications but are ineffective at extreme frequencies, and involve rigorous fabrication concessions in the implementation of RF, microwave, and millimeter-wave components. This is due to wavelengths being short at higher frequencies. Waveguide devices, on the other hand, are ideal for higher frequency systems, but are very costly, hard to fabricate, and challenging to integrate with planar components in the neighborhood. SIW connects the gap that existed between conventional air-filled rectangular waveguide and planar transmission line technologies including the microstrip. This study explores the current advancements and new opportunities in SIW implementation of RF and microwave devices including filters, multiplexers (diplexers and triplexers), power dividers/combiners, antennas, and sensors for modern communication systems.

Manufacturing of Pure Iron by Cold Rolling and Investigation for Application in Magnetic Flux Shielding.

The presented work investigates a novel method to manufacture 98.8% pure iron strips having high permeability and better saturation flux density for application in magnetic flux shielding. The proposed method uses electro-deposition and cold rolling along with intermediate annealing in a controlled environment to manufacture 0.05–0.5 mm thick pure iron strips. The presented approach is inexpensive, has better control over scaling/oxidation and requires low energy than that of the conventional methods of pure iron manufacturing by pyrometallurgical methods. Important magnetic and mechanical properties of the pure iron are investigated in the context of the application of the material in magnetic shielding. Magnetic properties of the material are investigated by following IEC60404-4 standard and toroidal coil test to determine hysteresis curve, magnetic permeability and core losses. The microstructure is investigated with an optical microscope and scanning electron microscopy to study grain size and defects after cold rolling and annealing. The properties derived from the experimental methods are used in finite element analysis to study the application of the material for static, low-frequency and high-frequency magnetic shielding. Theoretical simulation results for magnetic shielding around a current-carrying conductor and micro-electromechanical inductive sensor system are discussed. Further shielding performance of the material is compared with that of the other candidate materials, including that of Mu-metal and electrical steel. It is demonstrated that the pure iron strips manufactured in the present study can be used for magnetic shielding in the case of low-frequency applications. In the case of high-frequency applications, a conducting layer can be combined to ensure the required shielding effectiveness in the case of Class 2 applications.

Inductanceless high order low frequency filters for medical applications

&lt;p&gt;In this paper, a designed circuit used for low-frequency filters is implemented and realized the filter is based on frequency-dependent negative resistance (FDNR) as an inductor simulator to substitute the traditional inductance, which is heavy and high cost due to the coil material manufacturing and size area. The simulator is based on an active operation amplifier or operation transconductance amplifier (OTA) that is easy to build in an integrated circuit with a minimum number of components. The third and higher-order Butterworth filter is simulated at low frequency for low pass filter to use in medical instruments and low-frequency applications. The designed circuit is compared with the traditional proportional integral controller enhanced (PIE) and T section ordinary filter. The results with magnitude and phase response were compared and an acceptable result is obtained. The filter can be used for general applications such as medical and other low-frequency filters needed.&lt;/p&gt;

A rotational hybrid energy harvester utilizing bistability for low-frequency applications: Modelling and experimental validation

Rotational energy harvesting is one of the promising approaches for realizing self-powered wireless sensor networks. Incorporation of hybrid energy sources and geometric bistable nonlinearity can be a solution to enhance the energy harvesting performance under low-frequency excitations. This paper proposes a gravity-based rotational hybrid energy harvester by using the bistable mechanism for low-frequency applications. A comprehensive theoretical model considering the newly introduced piezoelectric stack and force magnification frame is derived for the first time based on the extended Hamilton’s principle. The piezoelectric and electromagnetic coupling coefficients are explicitly expressed and analysed. Both numerical and experimental results show that increasing the spring stiffness can amplify the harvested energy at a higher excitation frequency, and narrowing the impact gap can broaden the effective working bandwidth. Furthermore, the maximum power usually occurs with the impact inter-well phenomenon, after which the chaotic and intra-well oscillations appear successively. Besides, the maximum total power output of 2.98 mW is generated at 7.5 Hz with spring stiffness of 4200 N m−1, which is at least one order of magnitude higher than the other state-of-the-art energy harvesters under the same excitation. Based on the validated theoretical model, parametric studies are further performed to investigate the effects of the proof mass and the initial prestress on the piezoelectric stack. It is found that the hybrid rotational energy harvesting system can possess high tunability and adaptability to the frequency-variant environment by adjusting multiple structural parameters.

Transducer design for low-frequency circular close-packed array and its mutual radiation analysis.

Conventional flextensional transducers possess advantages of low frequency, small dimension, and high power [K. D. Rolt, J. Acoust. Soc. Am. 87, 1340 (1990)]. The low-frequency circular array composed of flextensional transducers has a strong mutual radiation effect due to the large vibration amplitude of the radiation surface located inside the circular array and the close distance between array elements [Z. Y. He et al., AIP Conf. Proc. 1272, 345 (2010)]. Here, a single-sided radiation flextensional transducer (SSR FT) is designed for a low-frequency circular close-packed array to diminish the mutual radiation effect. On the basis of the vibration principle of SSR FT, effects of structural parameters on electroacoustic, vibration, and radiation performance are studied for the final design of the transducer. Subsequently, the mutual radiation effect of circular close-packed arrays composed of SSR FTs and their counterparts is qualitatively analyzed on the basis of resonant mass, equivalent circuit, and numerical simulations. Finally, fabricated and tested circular arrays lead to a conclusion that the circular array composed of SSR FTs has a weaker mutual radiation effect and smaller dimensions than its counterpart composed of class IV FTs [K. P. B. Moosad, G. Chandrashekar, M. J. Joseph, and R. John, Appl. Acoust. 72, 127-131 (2011)]. The results confirm that the circular close-packed array provides flexibility in the application of low-frequency and small-dimension underwater acoustic sources.

Design, development, and theoretical and experimental tests of a nonlinear energy harvester via piezoelectric arrays and motion limiters

This paper presents the design, development and test of a nonlinear piezoelectric energy harvesting array with wideband performance under directly and parametrically excited conditions; theoretical verifications of equation-type as well as finite-element-methods are also provided. The array, as the core element, consists of four cantilever beams with attached piezoelectric layers and individual tip masses; two pairs of motion limiters were designed to limit the cantilever motions. By introducing 1-pair motion limiters, a strong hardening frequency response extended the system resonance regime and generated an enhanced bandwidth; when the monotonically increased system response triggered engagement with 2-pair motion limiters, the operational bandwidth was even further extended and formed a fully merged resonance regime for energy harvesting purposes. With motion limiters, the directly excited device achieved a continuous operational frequency bandwidth from 5.7 Hz to 12.3 Hz, which is a frequency bandwidth increase of 240%; by introducing the nonlinear frequency response in parametric resonance to the proposed device, the operational frequency bandwidth is increased by 579%. The corresponding piezoelectric voltage output of the proposed device is compared with conventional no limiter and one limiter counterparts. Theoretical investigations using an equation for the motion of the system along with a time-integration solution, as well as a finite element method using ANSYS, have been carried out to verify the results, showing good agreement. The results reveal that the proposed device has potential for dealing with different excitation levels and low frequency applications while broadening the frequency bandwidth.

EMI Reducing Interdigital Slot on Reference Planes of the PCBs

In some very low noise mixed-signal circuits, designers may use intentional slots in order to create a better isolation between a noisy digital ground and a very quiet analog ground, especially in low-frequency applications ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$&lt; $</tex-math></inline-formula> 1 MHz) when the current spread in the return plane may interfere with the quiet analog ground. Traces on the signal planes, crossing over these slots, are well-known sources for electromagnetic interference (EMI) due to discontinuities on the return current path. This article presents a novel interdigital slot structure used in the reference planes. The interdigital structure increases the coupling and, hence, provides a low impedance path for the return current of the signal line. This, in return, significantly reduces the radiated emission level in the printed circuit boards (PCBs). Furthermore, due to the periodic nature of transmission lines and the slow-wave effect provided by the interdigital structure, the periodically repeating resonance frequencies of the interdigital defect can be tuned by simply changing the geometric parameters such as digit length and the number of digits. It is shown that the electromagnetic radiation from these slots exhibits peak levels at these antiresonance frequencies, which are also the transmission zeros of the circuit. Conversely, radiation levels are minimized at passbands, where a good signal transmission is achieved. Therefore, this relationship would allow designers to tune the slot length to minimize radiation at the frequency of the signal passing through the trace. Four PCBs with three different-size interdigital structures and a traditional slot structure are first simulated and then fabricated. Well-agreed simulation and measurement results show that the EMI is suppressed by as much as 30 dB within the frequency range of 250 MHz–1 GHz. The radiation peaks and dips match with the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$S_{21}$</tex-math></inline-formula> minima (transmission zeros) and maxima, respectively, in measurement results as well.

Simulation & analysis of PZT/ P (VDF-TrFE) cantilever beams for health monitoring of building and structures

The design of a piezoelectric PZT/P(VDF-TrFE) based Microelectromechanical system cantilever beams for a very low frequency applications, using silicon bulk-micromachining technology is described in this paper. The natural frequencies of cantilever beams were calculated using the COMSOL software. For signal output, the cantilever-beam structure contains a layer of PZT/P(VDF-TrFE) as well as chrome-gold interdigitated electrodes. According to the simulation results, the cantilever-beam with dimensions of 10mmx3mmx5µm has a lowest resonant frequency of 95.56 Hz, implying that PZT/P(VDF-TrFE) is an appropriate piezoelectric material for really low frequency uses such as building and structure health monitoring.

Fiber based high power low noise single frequency lasers and applications

Fiber based high power low noise single frequency lasers and applications

Design of Cylindrical Surrounding Double-Gate MOSFET With Fabrication Steps Using a Layer-by-Layer Approach

The semiconductors with nanometer-scale are subjected to various patterns and scaling using the latest technology. The most widely used methods are top-down approaches in the design of complex heterostructures. The top-down approach involves the photolithography to ion sequentially beaming of the materials. In this context, the alternative layer-by-layer approach with cylindrical structures has been discussed and supported by the subsequent results to make Cylindrical Surrounding Double-Gate (CSDG) MOSFETs in this research work. This method involves the making of cylindrical structures with high-resolution morphological structures of CSDG MOSFETs. The process has been described in detail to design the CSDG MOSFETs with high-ƙ dielectric materials to make them suitable for low-frequency RF applications. The fast modulation of the Single Nano Wire (SNW) has been adopted for complex heterostructure modeling. The high-ƙ dielectric materials are placed in between the spacer and the gate material to overcome the Short Channel Effects (SCEs). This method produces symmetrical and concentric cylindrical structures of the CSDG MOSFETs with suitable layers. The minimum layer thickness achieved is about 10 nm axial length along with the core of the SNW. This gives enough insight for the proposed cylindrical structure to fabricate over the core of 2DEG. In this type of structure development, many cylindrical structures with various properties can be designed. The parameters focused on the cylindrical structure will be periodic, non-periodic, symmetric, asymmetric structures, and gaps/dots of nanometer scale. This innovative method introduces the method of designing the symmetric CSDG MOSFET concerning the center core. In this work, the authors focus on the suitable novel technique of designing cylindrical structures with unique dimensions and physical properties using various semiconductor materials.

Biaxial FBG Vibration Sensor With a Single Edge Filter and Matching Demodulation

This work developed, simulated, and characterized a high sensitivity vibration sensor for low-frequency applications. The fiber Bragg grating (FBG) overlapping method was used to demodulate the wavelength shift of the sensing gratings, but only one FBG for each axis was utilized (unlike two FBGs in the common approach), along with another one acting as a filter for both axes and temperature compensator; this enhanced method could measure acceleration in two axes simultaneously, although only the X-axis had constant sensibility in the entire operating range. The difficulty in achieving constant sensitivity in both axes lies in the need to match three Bragg gratings, resulting in a set of gratings with similar Bragg wavelengths. The new results showed constant sensitivity in both accelerometer axes (0.735 and 0.684 V∙m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> ∙ s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> for the X- and Y-axis, respectively). The usable frequency and acceleration amplitude ranges were from 0.5 to 20 Hz and from 14 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-3</sup> to 9 m/s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> , respectively, which both meet the requirements for detecting seismic-induced movements. Furthermore, the present results demonstrate that we can utilize a smaller number of gratings in accelerometer development compared to the common approach.

A facile method to enhance the flexibility and triboelectric output of PDMS using ionic liquid-coated single-wall carbon nanotubes

Energy harvesting devices based on triboelectric effect have gained much attention recently due to their significant potential in low-frequency applications, especially in wearable electronics. To enable these devices, flexible materials with relatively high electrical conductivity and large triboelectric output are needed. In this study, a PDMS composite is fabricated using embedded ionic liquid (IL) coated single-wall carbon nanotubes (SWCNTs). The ratio of IL to SWCNTs is tuned to achieve the desired material properties for wearable triboelectric nanogenerators. The SWCNT-IL-PDMS (IL: SWCNT= 20:1) composite exhibits a relatively high electrical conductivity (0.004 S/m) and an enhanced triboelectric output compared to unmodified PDMS. Specifically, the open-circuit voltage (Voc) and the short-circuit current (Isc) are increased by three folds. The relatively high electrical conductivity enables the composite to transfer charges without electrodes and reduces the internal impedance of triboelectric nanogenerators. The flexibility of the composite is also improved, as demonstrated by the decrease in both the tensile and compressive elastic moduli. In addition, the mechanism behind the change in electrical properties and triboelectric output is proposed and discussed in this paper. Specifically, the increase in the dielectric constant and electrical conductivity of the composites with IL is likely due to the better dispersion of SWCNT in the polymer matrix, and the change in the triboelectric output is a result of (1) the trade-off between dielectric constant and electrical conductivity, and (2) the shifting of triboelectric polarity with the addition of IL. This study not only provides a facile method to simultaneously increase the flexibility, electrical conductivity, and triboelectric output of polydimethylsiloxane (PDMS), but also generalizes the approach and paves the way to explore new flexible and electrically conductive materials for wearable triboelectric nanogenerators.

Application of Very Low Frequency (VLF) Method for Estimating Karst Underground River in Tanjungsari District

Drought is the main problem for clean water needs in Tanjungsari district. This research aims to provide information on the existence of underground river for deep well drilling. The methods used are geologic-structural analysis and application of Very Low Frequency (VLF) methods. Strike and dip measurements of 150 joints were conducted in the research area. Analysis using rosette diagram shows that the main geologic-structure orientation has a direction of Northwest - Southeast and Northeast – Southwest. Very Low Frequency (VLF) acquisition was measured across the possible occurrence of subsurface water flow directions predicted from geologic-structural analysis. The length of the VLF acquisition line is 2500 meters with 30 m spacing and 108 points acquisitions. The direction of VLF line is N 2700 E. The result shows that there are 2 locations that have high conductivity values, appearing at 1800 meters and 2200 meters. The results of this structural and VLF analyses indicate the existence of underground river at the location of 454326 N, 9105870 E.

Design and Implementation of 6 × 6 Array Piezoelectric AlN Hydrophone With High Sensitivity

This paper presents the design, fabrication and characterization of a MEMS piezoelectric hydrophone based on Silicon-On-Insulator (SOI), using Aluminum Nitride (AlN) as the functional piezoelectrical material. The hydrophone has a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${6}\times {6}$ </tex-math></inline-formula> array and a sandwich structure composed of Molybdenum-Aluminum-Molybdenum (Mo-AlN-Mo) films. The three-layered films adhere back cavities that have a radius of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$200~ \boldsymbol {\mu }\text{m}$ </tex-math></inline-formula> and a pitch of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$400~ \boldsymbol {\mu }\text{m}$ </tex-math></inline-formula> . The hydrophone shows proximal resonance frequencies of 479 kHz and 476 kHz under Impedance and Doppler tests, respectively. The initial deformation of the diaphragm is avoided by using a hollow PCB in the packaging to keep the hydrophone in a pressure-equalizing environment. The hydrophone is characterized in both water and air platforms. In water, the hydrophone has a sensitivity of −172.6 dB in the range of 100-2000 Hz, and a linearity of 99% at 1000 Hz, whereas in air it has a linearity of 98% at 1000 Hz. These results demonstrate the potential of high performance miniaturized hydrophone systems for wide-band and low-frequency applications.

Design, Simulation and Analysis of Perforated RF MEMS Capacitive Shunt Switch

Objective: This paper presents the design and simulation of double bridge-type capacitive RF MEMS switch by using FEM Tool. Methods: It is mainly concentrated on a low pull-in voltage, capacitance, and RF analysis. The beam is considered as a gold metal having the length of 595 μm along with the 1μm thickness and the dielectric is taken as Silicon nitride (Si3N4) by using Ashby’s method. The non-uniform meandering technique and perforations are used to reduce the pull-in voltage, by changing different beam thickness, air gap and materials. Results: The pull-in voltage of the proposed RF MEMS switch is 1.2 V. The scattering parameters are simulated by using Ansoft HFSS software. The simulation results of S-parameters such as return loss, insertion losses are, -19.27 dB and -0.20dB. The switch having good isolation is -63.94 dB at 8 GHz. Conclusion: The overall switch is designed with different beam thickness, various gap, and different materials to identify the best performance of the switch for low-frequency applications i.e X-bands.

Acoustic bandgaps in polyatomic chains of 3D-printed resonators

Acoustic bandgaps are ranges of frequencies in a medium at which sound cannot propagate. The classical model often used in solid-state physics is that of a 1D chain of masses and springs, the analysis of which can predict the speed of sound in a material, its dispersive nature, and any forbidden sound frequencies. We use a lumped parameter model for the acoustic inertance and compliance of pipes and cavities to create 1D monatomic, diatomic, and triatomic chains that demonstrate these acoustic bandgaps experimentally. The ease of 3D-printing these devices means that this method can be used to explore bandgap engineering in acoustic systems for low-frequency applications and used as a simple platform for creating acoustic analogs of the solid-state physical problem. Furthermore, it allows us to explore novel polyatomic behavior (e.g., tetratomic and pentatomic) and could ultimately find use as filters for experiments requiring miniaturized acoustic isolation.

A fast tool for the parametric analysis of human body exposed to LF electromagnetic fields in biomedical applications

A numerical procedure for analyzing electromagnetic (EM) fields interactions with biological tissues is presented. The proposed approach aims at drastically reducing the computational burden required by the repeated solution of large scale problems involving the interaction of the human body with EM fields, such as in the study of the time evolution of EM fields, uncertainty quantification, and inverse problems. The proposed volume integral equation (VIE), focused on low frequency applications, is a system of integral equations in terms of current density and scalar potential in the biological tissues excited by EM fields and/or electrodes connected to the human body. The proposed formulation requires the voxelization of the human body and takes advantage of the regularity of such discretization by speeding-up the computational procedure. Moreover, it exploits recent advancements in the solution of VIE by means of iterative preconditioned solvers and ad hoc parametric Model Order Reduction techniques. The efficiency of the proposed tool is demonstrated by applying it to a couple of realistic model problems: the assessment of the peripheral nerve stimulation, performed in terms of evaluation of the induced electric field, due to the gradient coils of a magnetic resonance imaging scanner during a clinical examination and the assessment of the exposure to environmental fields at 50 Hz of live-line workers with uncertain properties of the biological tissues. Thanks to the proposed method, uncertainty quantification analyses and time domain simulations are possible even for large scale problems and they can be performed on standard computers and reasonable computation time. Sample implementation of the method is made publicly available at https://github.com/UniPD-DII-ETCOMP/BioMOR.

Dynamic Finite-Element analysis of a soft bending actuator

Compliance is both a blessing and a curse in the soft robotics field. Increased flexibility comes with serious challenges in the dynamic modeling of compliant manipulators. Soft bending actuators, with their widespread application in rehabilitative, locomotive, and manipulative robotics, are no exception. Dynamic modeling of these actuators is specifically important, as it directly affects the design criteria. In other words, the effect of geometrical features on different aspects of dynamic response such as natural frequencies or magnitude and phase responses should be investigated. Since analytical modeling of their dynamic response is extremely challenging due to the high nonlinearity of both their geometrical and material features, the Finite-Element method is regarded as a proper technique to model these actuators and gain more insight into their dynamical behavior. This study presents a Finite-Element model to describe the dynamic behavior of a pneumatically-driven soft bending actuator, including an analysis of its natural frequencies and response shape. Since inflation of the actuator impacts its structural stiffness and geometrical domain, its effect is studied on the first five natural frequencies by modeling it as a prestress. The proposed model has been scripted and analyzed in ABAQUS, regarding its hyperelastic material behavior, and then is verified experimentally by comparing the numerical analysis data with the results obtained from the bending behavior of a fabricated prototype in different frequencies. In addition to a favorable match between model and test data, a design platform is presented regarding the effect of changes in length and different thicknesses on the bending angle and curvature. Moreover, it is discovered that the geometrical features of the actuator do not endanger the assumption that its bending shape has a constant curvature. In fact, this assumption is only valid in low-frequency applications.