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This paper aims to develop a resonant accelerometer for structure optimization. The dynamic analysis of the resonator for resonant accelerometer are investigated.

First, the working principle and mechanical model of the resonator are introduced. Moreover, dynamic analysis of the resonator is used for the purpose of investigating the dynamic characteristics of the resonant accelerometer. Finally, to verify the feasibility of the proposed dynamic analysis method, resonant accelerometer 1g static tumbling experiments of resonant accelerometer are built.

It can be seen from the natural frequency and the resonator mode that only when the resonator root stiffness is much greater than the resonant beam stiffness, there will be appear corresponding interference mode, therefore,the resonator root stiffness is avoid too large in design. The stability analysis result of resonant beam under axial force show that the resonant beam parameters should be maintained a constant. At the same time, it is concluded from the vibration mode analysis for resonant beam that the influence of the beam thickness and beam errors on the first and second order modes is great. On the other hand, it is concluded from the test result that the designed resonant accelerometer sensitivity is 98 Hz/g, which shows that the dynamic analysis method is feasible.

The research may be significant in the field of resonant sensors, supporting a variety of practical applications such as phone and game.

This paper seeks to establish a foundation for designing and optimizing resonant accelerometer structure. To this end, the dynamic analytical method of the resonator for resonant accelerometer was discussed. The results of this research have proved that the dynamic analysis based on a resonator is an effective approach and instructional in practical resonant sensor design.

This paper aims to provide detailed information on the dynamic model and closed‐loop control theory for a resonant accelerometer based on electrostatic stiffness, which is important for the design of this type of resonant accelerometer.

After analysing the principles of the resonant accelerometer based on electrostatic stiffness, a dynamic model was built. According to the requirements of the closed‐loop control, the control equations based on phase‐locked technology were also built for the system. With the help of the averaging method, the system behaviour was analysed, and the equilibrium for the vibration amplitude was achieved.

The theoretical analysis and simulation show that integral gain is critical to system stability. When it is larger than the critical point, the system stable time is shorter, but the frequency‐tracking process fluctuates; if it is smaller than the critical point, the system stable time is longer, and the frequency‐tracking process stabilizes a resonant accelerometer was fabricated with a bulk‐silicon‐dissolved process. With the above conclusions, the accelerometer was driven and tested with a sensitivity of 47 Hz/g for a single vibration beam.

The dynamic model and the control theory for the resonant accelerometer based on electrostatic stiffness were presented in this paper. The simulation and experiment results agree well with the theoretical analysis.

Being the key sensitive elements of the micro-electromechanical systems (MEMS) resonant sensors, performance of the double-ended tuning fork (DETF) will affect precision of the whole sensor greatly. Currently, most of the research on DETF is concentrated on ideal theory or simply mentioned as part of the sensor. But, in most engineering occasions, there exists many factors such as the additional mass, air damping and fabrication process, etc. However, few references are individually aimed at the mechanical characters of DETF. To choose the suitable DETF, it is important to solely research and measure the performance of this element.

In this paper, the authors combine the practical engineering applications and deduce the calculation method of sensitive element’s resonant frequency under various circumstances. The authors also design a force-generating system to make the loading simulation and verify the correctness of theory.

On the basis of Euler–Bernoulli theory and Rayleigh’s equation, frequency theories of DETF under four different situations have been deduced. A force-generating device is designed and fabricated to measure the mechanical characters of the DETF. The experiments using force-generating system, DETF, the high performance laser vibrometer and oscillograph are carried out. It verifies the correctness of theory.

Currently, most of the research on DETF is concentrated on ideal theory or simply mentioned as part of the sensor, and few references are individually aimed at the mechanical characters of DETF. Combining the practical engineering applications, the authors deduced the frequency theories of DETF. A force-generating system is designed and fabricated to measure the mechanical characters of the DETF, and the experiment results match the theoretical results very well.

This paper aims to provide a focused review on the geometrical designs for performance enhancement of piezoresistive microaccelerometers.

By analyzing working principle and conventional geometries, the improved research proposals are sorted into three groups in terms of their anticipated objectives, including sensitivity, resonant frequency and cross-axis sensitivity. Accessible methods are outlined and their merits and demerits are described.

Novel geometries obviously enhance the performance of accelerometers, and the efficacy can be further elevated by newer materials and fabrication processes.

This paper mainly focused on the improved geometrical designs for sensitivity, resonant frequency and cross-axis sensitivity. Other performance parameters or design schemes are not included in this paper.

This paper generalizes the available geometries and methods for the enhancement of sensitivity, resonant frequency and cross-axis sensitivity in piezoresistive accelerometers design.

The purpose of this study is to present the state of the art for fiber Bragg grating (FBG) acceleration sensing technologies from two aspects: the principle of the measurement dimension and the principle of the sensing configuration. Some commercial sensors have also been introduced and future work in this field has also been discussed. This paper could provide an important reference for the research community.

This review is to present the state of the art for FBG acceleration sensing technologies from two aspects: the principle of the measurement dimension (one-dimension and multi-dimension) and the principle of the sensing configuration (beam type, radial vibration type, axial vibration type and other composite structures).

The current research on developing FBG acceleration sensors is mainly focused on the sensing method, the construction and design of the elastic structure and the design of a new information detection method. This paper hypothesizes that in the future, the following research trends will be strengthened: common single-mode fiber grating of the low cost and high utilization rate; high sensitivity and strength special fiber grating; multi-core fiber grating for measuring single-parameter multi-dimensional information or multi-parameter information; demodulating equipment of low cost, small volume and high sampling frequency.

The principle of the measurement dimension and principle of the sensing configuration for FBG acceleration sensors have been introduced, which could provide an important reference for the research community.

In this work, the paper aims to demonstrate the feasibility of plastic optical fiber (POF) based accelerometers for the structural health monitoring (SHM) of civil engineering structures based on measurements of their dynamic response, namely to estimate natural frequencies. These sensors use POFs, combining the advantages of the optical technology with the robustness of this particular kind of fiber. The POF sensor output is directly compared with the signal from an electrical sensor, demonstrating the potential use of such sensors in structural monitoring applications.

Within this work, the paper demonstrates the feasibility of using a low-cost acceleration system based on a POF accelerometer on the dynamic monitoring of a civil engineering structure, aiming its natural frequency evaluation, which is a primary parameter to be used in SHM methods and numerical models calibration.

A low-cost POF-based accelerometer was used in the characterization of a civil engineering structural component, located in a building at the University of Aveiro Campus, being used to estimate its natural frequency with a relative error of 0.36 percent, comparatively to the value estimated recurring to a calibrated electronic sensor.

Optical fiber sensors take advantage of the fibers properties, such as immunity to electromagnetic interference and electrical isolation. They are very attractive for use in hostile environments, like submerse environments or flammable atmospheres where electrical currents might pose a hazard. The advantages of POF itself should also be considered, like resistance to hash environments, robustness, flexibility, low-cost interrogation units and high numeric aperture (lower cost components). The paper demonstrates the feasibility of using a low-cost acceleration system based on a POF accelerometer on the dynamic monitoring of a civil engineering structure, aiming its natural frequency evaluation.

The natural frequency of a diaphragm with residual stress in contact with a liquid is investigated theoretically in this paper. The paper aims to discuss these issues.

An analytical calculation using the nondimensional added virtual mass incremental (NAVMI) factors is performed to find the dependency of the natural frequency on the residual stress when the diaphragm vibrating in contact with a liquid.

The analysis gives the residual stress contribution to the added virtual mass.

The magnitude of the added virtual mass depends on the residual stress. However, the magnitude of the natural frequency is found to be insignificant to the residual stress.

The processing techniques and materials utilized in the fabrication of a two-terminal electrostatically actuated micro-electro-mechanical cantilever-arrayed device used for radio frequency tuning applications are presented in this work. The paper aims to discuss these issues.

The process, which is based on silicon surface micromachining, uses spin-coated photoresist as the sacrificial layer underneath the electroplated gold structural material and an insulating layer of silicon dioxide, deposited using plasma enhanced chemical vapour deposition (PECVD), to avoid a short circuit between the cantilever and the bottom electrode in a total of six major fabrication steps. These included the PECVD of the silicon dioxide insulating layer, optical lithography to transfer photomask layer patterns, vacuum evaporation to deposit thin films of titanium (Ti) and gold (Au), electroplating of Au, the dry release of the cantilever beam arrays, and finally the wafer dicing to split the different micro devices. These process steps were each sub-detailed to give a total of 14 micro-fabrication processes.

Scanning electron microscope images taken on the final fabricated device that was dry released using oxygen plasma ashing to avoid stiction showed 12 freely suspended micro-cantilevered beams suspended with an average electrostatic gap of 2.29±0.17 μm above a 4,934±3 Å thick silicon dioxide layer. Preliminary dimensional measurements on the fabricated devices revealed that the cantilevers were at least 52.06±1.93 μm wide with lengths varying from 377.97±0.01 to 1,491.89±0.01 μm and were at least 2.21±0.05 μm thick.

The cantilever beams used in this work were manufactured using electroplated gold, and photoresist was used as a sacrificial layer underneath the beams. Plasma ashing was used to release the beams. The beams were anchored to a central electrode and each beam was designed with varying length.

The purpose of this paper is to develop the device made of low temperature co-fired ceramics (LTCC) and lead zirconate titanate (PZT) by co-firing both materials. In the paper, the technology and properties of a miniature uniaxial ceramic accelerometer are presented.

Finite element method (FEM) is applied to predict properties of the sensor vs main dimensions of the sensor. The LTCC process is applied during manufacturing of the device. All the advantages of the technology are taken into account during designing three-dimensional structure of the sensor. The sensitivity and resonant frequency of the accelerometer are measured. Real material parameters of PZT are estimated according to measurement results and FEM simulations.

The ceramic sensor integrated with SMD package with outer dimensions of 5 × 5 × 5 mm3 is manufactured. The accelerometer exhibits sensitivity of 0.75 pC/g measured at 100 Hz. The resonant frequency is equal to about 2 kHz. Useful frequency range is limited by 3 dB sensitivity change at about 1 kHz.

Sensitivity of the device is limited by interaction between LTCC and PZT materials during co-firing process. The estimated d parameters are ten times worse comparing to bulk Pz27 material. Further research on materials compatibility should be carried out.

The sensor can be easily integrated into various devices made of standard electronic printed circuit boards (PCBs). Applied method of direct integration of piezoelectric transducers with LTCC material enables manufacturing of complex ceramic systems with built-in accelerometer in the substrate.

The accelerometer is a sensor and a package simultaneously. The miniature ceramic device is compatible with surface mounting technology; hence, it can be used directly on PCBs for vibration monitoring inside electronic devices and systems.

This paper aims to present an efficient design approach for the micro electromechanical systems (MEMS) accelerometers considering design parameters affecting the long-term reliability of these inertial sensors in comparison to traditional iterative microfabrication and experimental characterization approach.

A dual-axis capacitive MEMS accelerometer design is presented considering the microfabrication process constraints of the foundry process. The performance of the MEMS accelerometer is analyzed through finite element method– based simulations considering main design parameters affecting the long-term reliability. The effect of microfabrication process induced residual stress, operating pressure variations in the range of 10 mTorr to atmospheric pressure, thermal variations in the operating temperature range of −40°C to 100°C and impulsive input acceleration at different input frequency values is presented in detail.

The effect of residual stress is negligible on performance of the MEMS accelerometer due to efficient design of mechanical suspension beams. The effect of operating temperature and pressure variations is negligible on energy loss factor. The thermal strain at high temperature causes the sensing plates to deform out of plane. The input dynamic acceleration range is 34 g at room temperature, which decreases with operating temperature variations. At low frequency input acceleration, the input acts as a quasi-static load, whereas at high frequency, it acts as a dynamic load for the MEMS accelerometer.

In comparison with the traditional MEMS accelerometer design approaches, the proposed design approach focuses on the analysis of critical design parameters that affect the long-term reliability of MEMS accelerometer.