Microelectromechanical Sensors Research Articles

A Comprehensive Review on the Optical Micro-Electromechanical Sensors for the Biomedical Application.

This study presented an overview of current developments in optical micro-electromechanical systems in biomedical applications. Optical micro-electromechanical system (MEMS) is a particular class of MEMS technology. It combines micro-optics, mechanical elements, and electronics, called the micro-opto electromechanical system (MOEMS). Optical MEMS comprises sensing and influencing optical signals on micron-level by incorporating mechanical, electrical, and optical systems. Optical MEMS devices are widely used in inertial navigation, accelerometers, gyroscope application, and many industrial and biomedical applications. Due to its miniaturised size, insensitivity to electromagnetic interference, affordability, and lightweight characteristic, it can be easily integrated into the human body with a suitable design. This study presented a comprehensive review of 140 research articles published on photonic MEMS in biomedical applications that used the qualitative method to find the recent advancement, challenges, and issues. The paper also identified the critical success factors applied to design the optimum photonic MEMS devices in biomedical applications. With the systematic literature review approach, the results showed that the key design factors could significantly impact design, application, and future scope of work. The literature of this paper suggested that due to the flexibility, accuracy, design factors efficiency of the Fibre Bragg Grating (FBG) sensors, the demand has been increasing for various photonic devices. Except for FBG sensing devices, other sensing systems such as optical ring resonator, Mach-Zehnder interferometer (MZI), and photonic crystals are used, which still show experimental stages in the application of biosensing. Due to the requirement of sophisticated fabrication facilities and integrated systems, it is a tough choice to consider the other photonic system. Miniaturisation of complete FBG device for biomedical applications is the future scope of work. Even though there is a lot of experimental work considered with an FBG sensing system, commercialisation of the final FBG device for a specific application has not been seen noticeable progress in the past.

Influence of active structure parameters on resonant frequency of acoustic transducer membranes

The paper presents the results of calculations of the resonant frequency of a multilayer square membrane for ultrasonic microelectromechanical sensors. Various combinations of active layer materials and metal electrodes were taken into account. The dependences of the resonant frequency on the side length of membrane, as well as on the thickness of active piezoelectric layer and metal electrode for SiO2/Ti/ZnO, SiO2/Al/ZnO, SiO2/Ti/PZT and SiO2/Al/PZT structures were ob-tained. According to the calculations, the values of the resonant frequencies are in the ranges of 46.1–498.3 kHz for SiO2/Ti/ZnO; 45.4–477.3 kHz for SiO2/Al/ZnO; 39.4–411.4 kHz for SiO2/Ti/PZT; 38.1–381 kHz for SiO2/Al/PZT. It is shown that the resonant frequency can be increased due to changes in the geometric parameters of the membrane; and the material and dimensions of the piezoelectric layer have the greatest influence. The results of analytical and numerical simulations for particular case of SiO2(1μm)/Ti(1μm)/ZnO(2μm)/Ti(1μm) membrane with a side length of 600 μm are also compared. The obtained results could be used to optimize the design and process technology of microelectrome-chanical ultrasonic sensors.

Analysis of the possibility of creating an acoustic velocity sensor using GaN epitaxial films

This paper results in results of analyzing the possibility of creating an acoustic velocity sensor using epitaxial GaN films. Technology for the fabrication of a microelectromechanical acoustic velocity sensor was developed and a prototype of the sensor was produced. The simulation of the characteristics of the obtained acoustic velocity sensors was carried out on the basis of the measured electrical characteristics, where the sensitivity and the directional pattern were determined.

Optoelectronic Navigation System for a Flexible Surgical Instrument Based on Inertial Microelectromechanical Sensors

Optoelectronic Navigation System for a Flexible Surgical Instrument Based on Inertial Microelectromechanical Sensors

Development of MEMS composite sensor with temperature compensation for tire pressure monitoring system

The pressure and temperature inside the tire is mainly monitored by the tire pressure monitoring system (TPMS). In order to improve the integration of the TPMS system, moreover enhance the sensitivity and temperature-insensitivity of pressure measurement, this paper proposes a microelectromechanical (MEMS) chip-level sensor based on stress-sensitive aluminum–silicon hybrid structures with amplified piezoresistive effect and temperature-dependent aluminum–silicon hybrid structures for hardware and software temperature compensations. Two types of aluminum–silicon hybrid structures are located inside and outside the strained membrane to simultaneously realize the measurement of pressure and temperature. The model of this composite sensor chip is firstly designed and verified for its effectiveness by using finite element numerical simulation, and then it is fabricated based on the standard MEMS process. The experiments indicate that the pressure sensitivity of the sensor is between 0.126 mV/(V·kPa) and 0.151 mV/(V·kPa) during the ambient temperature ranges from −20 °C to 100 °C, while the measurement error, sensitivity and temperature coefficient of temperature-dependent hybrid structures are individually ±0.91 °C, −1.225 mV/(V °C) and −0.150% °C−1. The thermal coefficient of offset (TCO) of pressure measurement can be reduced from −3.553%FS °C−1 to −0.375%FS °C−1 based on the differential output of the proposed sensor. In order to obtain the better performance of temperature compensation, Elman neural network based on ant colony algorithm is applied in the data fusion of differential output to further eliminate the temperature drift error. Based on which, the overall measured error is within 3.45 kPa, which is less than ±1.15%FS. The TCO is −0.017%FS °C−1, and the thermal coefficient of span is −0.020%FS °C−1. The research results may provide a useful reference for the development of the high-performance MEMS composite sensor for the TPMS system.

Abstract 12517: CardioSignal Smartphone Application Detects Atrial Fibrillation in Heart Failure Population

Introduction: The micro-electromechanical sensors of a common smartphone can be used to detect vibrations caused by cardiac motion when the smartphone is placed on chest. With commonly available CardioSignal application (App) the concept has been shown to detect atrial fibrillation (AFib) in clinical setting from a 60 second recording. The CardioSignal smartphone app is a certified CE IIa-class medical device and intended to detect AFib in adult population. AFib and heart failure (HF) frequently coexist and together can lead to increased morbidity. To address this subgroup of individuals with increased risk of Afib, we examined how CardioSignal solution performs in Afib detection in a population of recent HF decompensation. Methods: From a total of 83 HF patients (mean age 64, 70 % men) motion sensor signals were collected and analyzed with the CardioSignal solution. The signals were collected by placing a smartphone on the chest of the patients in supine position. From the recordings two 60 second strips were analyzed. A simultaneous 1-lead ECG data was collected with an ECG patch from the V4 position. The signals were analyzed for quality and rhythm diagnostics from the ECG recording was by a cardiologist blinded for the CardioSignal solution result. Finally a head-to-head comparison was conducted for CardioSignal result and the ECG data. A positive finding for Afib was concluded if both 60 second recordings detected Afib for each person. Results: From the 83 HF patients 166 measurements were recorded. Out of the 166 measurements, 163 passed the quality check for the sensor signals. The preliminary analyses showed sensitivity of the AFib detection algorithm of 80.7% (95% CI 62.5% to 92.6%) and the specificity of 100.0% (93.1% to 100.0%). The positive predictive value was 100.0% and the negative predictive value 89.7% (80.9% to 94.7%). The accuracy was 92.8% (84.9% to 97.3%). Conclusions: A smartphone-based recording and analysis with CardioSignal solution in HF patients appear to be an effective and reliable method to detect possible Afib.

Performance analysis of MEMS-based inertial measurement units in terrestrial vehicles

In the recent period, Inertial Measurement Units (IMUs) are widely employed in many applications, such as smartphones, robotics, Unmanned Aerial vehicles, automotive and self‑driving vehicles, artificial intelligence, and numerous others. However, the dynamical metrological performances and the reliability analysis when these microelectronic devices operate under real environmental conditions are not sufficiently covered by scientific literature. Starting from standard tests for automotive applications, to emulate the real operating conditions of IMUs, a new test plan based on sine sweep vibration profiles has also been developed, including different service conditions characterized by the presence of a sinusoidal component with the addition of a random vibration noise typical of automotive scenarios. In-depth analysis has been carried out in the time and frequency domains leading to the employment of suitable figures of merit, highlighting the effects of mechanical stress on the metrological performances of microelectromechanical sensors. The developed test plan could be used to investigate if sinusoidal vibrations at specific frequencies influence the correct operation of low-cost platforms in typical automotive applications. The experimental results have confirmed the suitability of the proposed figures of merit in analyzing the effects of vibrations typical of the automotive context on the IMUs operating. In particular, they have allowed investigating the axes cross-sensitivity of triaxial systems, spurious responses, and unexpected behaviors due to the devices' non-ideality.

Feature Extraction and Data Analysis of Basketball Motion Postures: Acquisition With an Inertial Sensor

Abstract This paper mainly analyzed the application of inertial sensors in basketball posture analysis. The data of 20 basketball players in different postures were collected by Micro-electromechanical systems inertial sensors. The mean, variance, and skewness were taken as features to compare the performance of C4.5, random forest (RF), k-nearest neighbor, and support vector machine (SVM) algorithms in analyzing posture data. It was found that the classification accuracy of the k-nearest neighbor algorithm was around 90%, and the classification accuracy of C4.5, RF, and SVM algorithms was all above 90%. The classification accuracy of the RF algorithm was the highest (98.72%), which was significantly higher than C4.5 and SVM algorithms. The results verified the advantages of the RF algorithm in basketball posture analysis. The research results confirm the reliability of the inertial sensor in the field of motion posture analysis and make some contributions to its application in sport training. This paper provides support for the analysis of motion posture.

Estimation of Vehicle Speed from Pavement Stress Responses Using Wireless Sensors

Vehicle speed is a crucial input for mechanistic-based design and maintenance decision making of asphalt pavement. It can be measured using direct methods and indirect methods. Direct methods, such as video camera and inductive loops, have difficultly achieving real-time data processing and have a sophisticated installation process. Indirect methods use the mechanical responses collected by the traditional mechanical sensors to estimate speed. Although effective, these traditional mechanical sensors usually have a low survival rate and require highly sophisticated installation procedures. Recently, a new type of wireless micro-electromechanical sensor (MEMS), SmartRock (Sensor Technology Research Development and Application Laboratory, Hong Kong), has been promising in pavement research to monitor contact stress and acceleration at the particle level. This paper aims to explore the potential and reliability of using the SmartRock in acquiring vehicular speed and to evaluate the effect of loading amplitude and wandering effect (i.e., the loading location relative to the sensor or monitoring-point location) on speed estimation. In this study, SmartRock sensors were embedded in a semirigid pavement, and an accelerated pavement testing (APT) facility was used to apply loadings. Vehicle speed was estimated according to the dynamic stress responses (i.e., stress waves) measured by the SmartRock. In addition, a finite-element model was developed. After being calibrated by SmartRock stress data, this model, combined with SmartRock data, was used to evaluate the effect of load amplitude and wandering on the speed estimation. Findings indicate that SmartRock can reasonably estimate the vehicle speed using both time-domain and frequency-domain methods. The loading amplitude and wandering may have little effect on the speed estimation according to the results of this study, but future work is recommended to verify such findings.

Assessing and Modelling the Interactions of Instrumented Particles with Bed Surface at Low Transport Conditions

Sediment transport at near threshold to low transport stages (below the continuous transport) can still be affected by flow turbulence and its dynamics can benefit from further comprehensive studies. This study uses an instrumented particle embedded with micro electromechanical sensors (MEMS) to allow tracking the motions and forces acting on it, leading to and during its transport. Instrumented particle transport experiments were carried out at laboratory flume under a range of flow conditions. The probability distributions functions (PDFs) of bed load particle instantaneous velocities, hop distances and associated travel times (measured from start to stop of transport) were obtained for all the performed experiments with varying flow rates and particle density. The modelled distributions are useful and enable a deeper understanding of bed load sediment transport dynamics from a Lagrangian perspective. Furthermore, the results analyzed from the instrumented particle (including the particle’s transport mode) were validated using visual particle tracking methods (top and side cameras). The findings of this study demonstrate that for the range of turbulent flows trialed herein, the instrumented particle can be a useful, accessible, and low-cost tool for obtaining particle transport dynamics, having demonstrated satisfactory potential for field deployment in the near future.

Online Nonlinear Error Compensation Circuit Based on Neural Networks

Nonlinear errors of sensor output signals are common in the field of inertial measurement and can be compensated with statistical models or machine learning models. Machine learning solutions with large computational complexity are generally offline or implemented on additional hardware platforms, which are difficult to meet the high integration requirements of microelectromechanical system inertial sensors. This paper explored the feasibility of an online compensation scheme based on neural networks. In the designed solution, a simplified small-scale network is used for modeling, and the peak-to-peak value and standard deviation of the error after compensation are reduced to 17.00% and 16.95%, respectively. Additionally, a compensation circuit is designed based on the simplified modeling scheme. The results show that the circuit compensation effect is consistent with the results of the algorithm experiment. Under SMIC 180 nm complementary metal-oxide semiconductor (CMOS) technology, the circuit has a maximum operating frequency of 96 MHz and an area of 0.19 mm2. When the sampling signal frequency is 800 kHz, the power consumption is only 1.12 mW. This circuit can be used as a component of the measurement and control system on chip (SoC), which meets real-time application scenarios with low power consumption requirements.

Channel-Crack-Designed Suspended Sensing Membrane as a Fully Flexible Vibration Sensor with High Sensitivity and Dynamic Range.

Vibration sensors are essential for signal acquisition, motion measuring, and structural health evaluations in civil and industrial applications. However, the mechanical brittleness and complicated installation process of micro-electromechanical system vibration sensors block their applications in wearable devices and human-machine interaction. The development of flexible vibration sensors satisfying the requirements of good flexibility, high sensitivity, and the ability to attach conformably on curved critical components is highly demanded but still remains a challenge. Here, we demonstrate a highly sensitive and fully flexible vibration sensor with a channel-crack-designed suspended sensing membrane for high dynamic vibration and acceleration monitoring. The flexible sensor is designed as a suspended vibration membrane structure by bonding a channel-crack-sensing membrane on a cavity substrate, of which the suspended sensing membrane can freely vibrate out of plane under external vibration. By inducing the cracks to be generated in the embedded multiwalled carbon nanotube channels and fully cracked across the conducting routes, the suspended vibration membrane shows high sensitivity, good reproducibility, and robust sensing stability. The resultant vibration sensor demonstrates an ultrawide frequency vibration response range from 0.1 to 20,000 Hz and exhibits the ability to respond to acceleration vibration with a broad response of 0.24-100 m/s2. The high sensitivity, wide bandwidth, and fully flexible format of the vibration sensor enable it to be directly attached on human bodies and curvilinear surfaces to conduct in situ vibration sensing, which was demonstrated by motion detection, voice identification, and the vibration monitoring of mechanical equipment.

Group Intelligence Perception Applied in the Electromechanical Equipment Fault Intelligent Diagnosis Support System

The paper designs a fault diagnosis and monitoring system for electromechanical equipment based on group intelligence perception technology. The system uses the Internet of Things technology to establish a fault feature selection and fault diagnosis model for electromechanical equipment. At the same time, the system uses micro-electromechanical system sensors to realize real-time monitoring of electromechanical equipment, and realizes the collection and upload of status data and fault data of base electromechanical equipment. The design of this system allows all parties involved in electromechanical equipment such as users, manufacturers, maintainers, and industry experts to break through the constraints of time and space. All relevant parties can communicate in real time on the problems of the equipment, so that the electromechanical equipment can be more efficiently automated and intelligently maintained.

Enhancing the linear dynamic range of a mode-localized MEMS mass sensor with repulsive electrostatic actuation

This letter demonstrates the linear dynamic range enhancement of a mode-localized microelectromechanical systems sensor based on two weakly coupled cantilevers under electrostatic actuation resulting in a repulsive force. An analytical model is proposed to design the sensor, and the expression of the electrostatic force is obtained using a finite element simulation. Compared to attractive electrostatic actuation, the intensity of the resulting force is less sensitive to the change in the cantilever’s displacement, with negligible electrostatic nonlinearities. This result is confirmed by experimental measurements showing linear vibrations up to 70% of the gap, which is almost three times higher than the electrostatic critical amplitude of a similar device using attractive electrostatic force. Finally, the mass sensing capability is highlighted by depositing a few picograms of platinum on the sensor.

Review of flexible microelectromechanical system sensors and devices

Today, the vast majority of microelectromechanical system (MEMS) sensors are mechanically rigid and therefore suffer from disadvantages when used in intimately wearable or bio-integrated applications. By applying new engineering strategies, mechanically bendable and stretchable MEMS devices have been successfully demonstrated. This article reviews recent progress in this area, focusing on high-performance flexible devices based on inorganic thin films. We start with the common design and fabrication strategies for flexibility and stretchability, summarize the recent application-oriented flexible devices, and conclude with criteria and opportunities for the future development of flexible MEMS sensors.

Информационно-управляющая система сбора и передачи информации для безэкипажного судна

The article considers the principles of constructing and functioning the data collection and transmission system for developing an information and control system of an unmanned vessel. A problem of the information and control system developing is suggested in two stages: choosing methods and means of transmitting data from sensors to the data collection system, choosing the method of data transfer to the data collection system, implementing the data transmission channels; organizing data collection and storage for use in the autopilot device, implementing systems for receiving and synchronizing data and their placement in the storage system. There has been illustrated a block diagram of the information and control system for collecting and transmitting data for an unmanned vessel, which consists of two subsystems: data collection and data transmission. Selecting the main components and proposals on the software and hardware application is carried out. The detailed characteristics of the microcontroller, digital compass, microelectromechanical sensors and chartplotter are given. In the course of implementing the data collection system, a Maretron digital magnetic compass, CRM100 and CRM200 microelectromechanical sensors, which implement a yaw rate sensor and inclinometer, and an analog steering sensor were connected to the debug board. The software for the information and control system is written in the programming language using the STM32CubeIDE application development tools. It has been stated that the data transfer between different levels of the program is carried out using standard means of the program code.

Smart sensors to predict entrainment of freshwater mussels: A new tool in freshwater habitat assessment

1.The quantification and assessment of dynamic hydrogeomorphological processes is crucial in defining suitable habitat for aquatic benthic species. Yet a consistent approach to accurately record and monitor near-bed flow characteristics, remains largely undefined in freshwater ecology.2.The purpose of this work was to provide a direct, non-intrusive, low-cost and accessible tool to evaluate near-bed incipient flow conditions and predict when flow forcing results in the entrainment of individuals.3.This study designed, for the first time, an instrumented freshwater mussel, encompassing inertial microelectromechanical sensors (MEMS), housed within Margaritifera margaritifera shells.4.Following initial calibration of the embedded sensors to ensure accurate detection of three-dimensional displacement, dedicated flume experiments were undertaken to assess instrumented shell movement metrics, for a range of flow conditions and shell orientations.5.Analysis found that data from the sensors' readings could successfully detect, and potentially predict, entrainment events through the examination of variability in recordings of total acceleration, with entrainment risk shown to vary across flowrate, shell orientation and size.6.Instrumented shells could provide a valuable tool for assisting conservation management of freshwater mussel species: aiding the identification and monitoring of suitable habitat in reintroduction and restoration schemes. Instrumented shells could also assist habitat suitability surveys for a range of freshwater species, intimately linked to the physical environment of freshwater ecosystems.7.Evidence from this study suggests further research into this tool may yield methods for accurately predicting more complex flow metrics associated with hydraulic stress. It is therefore clear that the potential of this tool is still to be fully investigated.

Optimal calibration plan for inertial measurement unit based on microelectromechanical system

This paper is about the composition of scientifically substantiated calibration plan from the specific requirements for inertial measurement unit on microelectromechanical sensors. It is proposed to decompose the common problem into three tasks – converting implicit requirements to the explicit requirements with error components, determining of requirements by indirect parameters and finding direct parameter values, time limited calibration that have limits for full time. All these tasks may be presented as multi-criteria optimizations and be solved by numerical methods with some semi-analytical substitutions. Suggested methods are useful for composing an optimal calibration plan in conditions of ambiguous requirements, to estimate reaching accuracy, test volume and total calibration time. This approach offers the researcher a new look at the problem of balance between calibration accuracy and optimal use of resources.

Attitude determination in integrated GNSS-inertial navigation systems in information and measurement insufficiency conditions

The article presents the attitude determination algorithm for multi-antenna global navigation satellite and inertial integrated navigation system operating under information and measurement insufficiency conditions. The information and measurement insufficiency conditions are understood as the impossibility of the inertial system alignment on a fixed base and the absence of a redundant number of satellites to resolve the carrier phase integer ambiguity. The ability of the navigation system to operate in such conditions is achieved by combining several existing attitude determination methods and using the new method of attitude determination using ambiguous satellite phase measurements and absolute angular rate measurements. The hardware-in-the-loop simulation results using a 2-axis motion simulator and microelectromechanical systems inertial sensors are presented. The results confirm the efficiency of the proposed approach to the design of the navigation system algorithm.

Silicon nanostructure-based photonic MEMS sensor for biosensing application

We explored the design of an optical pressure sensor. The objective is to create a photonic microelectromechanical system-based cantilever sensor design to detect prostate-specific antigen, a protein biomarker associated with prostate cancer. Sensor’s performance for the early detection of cancerous cells is dependent on sensitivity. The designed sensor consists of a hexagonal ring integrated with microcantilevers. Two types of microcantilever such as rectangular profile and V profile with integrated photonic sensing layer are investigated for sensitivity, quality factor, and resonant wavelength. The analysis shows that a geometrical modification of microcantilever has a significant effect on sensitivity enhancement. The finite difference time domain tool is used for designing photonic ring resonator patches. Numerical analysis of microcantilever is considered to investigate surface stress behavior. The cantilever deformation due to applied pressure resulted in a change in the index of refraction. Results show that the sensitivity of 55 nm / MPa for a triangular-shaped microcantilever obtained is higher compared to the rectangular-shaped microcantilever with a sensitivity of 0.19 nm / MPa. The designed structures have significantly higher sensitivities than the previously published sensitivity of 3.27 nm / MPa at wavelength 1550 nm. The maximum quality factor obtained for the rectangular shape is 2852 and 77,510 for the triangular shape. Triangular-shaped microcantilever can minimize winding inflexibility or stiffness. This capability of the triangular-shaped microcantilever enhances feasibility in making the final packaging and future fabrication.