MEMS sensor Research Papers - Academia.edu (original) (raw)

Low-power and high-temperature sensors and MEMS designs based on bulk, SOI and IC compatible materials and processes are presented here. Target markets are in general public sensors for UV, ozone, CO, liquids presence, e.g. in mobile devices. Or in health, sensors for the medical diagnosis (DNA, RNA, bacteria, viruses). Simple, low cost and low consumption devices are required in medical applications. In our laboratory aluminum oxide interdigitated capacitors have been developed and successfully tested on DNA hybridization test on HIV and cancer (TP-53), as well as on bacteria and humidity or condensation (integrated into a wireless breathing monitoring system), all of them showing comparable results to the state of the art using existing standard biological protocols procedures that open new opportunities for Medical Applications. For UV light based detections (UV Diode), that are ready for use, packaging must be customized. Customers are the kits fabricator to integrate our device...

- by
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- Engineering, MEMS sensor, MEMS sensors, Low power CMOS Digital and Analog design
- by Ratul Majumdar
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- Microelectromechanical systems, Control Systems, MEMS sensor, Robots

MEMS on Moon! : MEMS Based Lunar Seismometer to primarily detect Moon quakes . Designed and fabricated at LEOS, Indian Space Research Organisation (ISRO) for Chandrayan 2 lunar Mission. The micro-seismometer is configured to pick low... more

- by Suhas EP
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- Seismology, Exploration Seismology, MEMS sensor, NanoTechnology, MEMS, Analog IC
- by Laurent A Francis
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- MEMS, MEMS sensor, Silicon on Insulator

The static and dynamic pull-in phenomenon of a functionally graded Al/Al 2 O 3 microplate, considering the damping coefficient and fringing field effects, has been analyzed because of its crucial effect in micro-electromechanical systems application, especially in microswitches. The nonlinear equation of motion of functionally graded microplate has been derived using Hamilton's principle, and solved analytically. Furthermore, a finite element code has been developed to solve the problem. Comparing the theoretical and numerical results for specific boundary conditions demonstrates that the numerical solution predicts the pull-in phenomenon with the least errors; and it can be used for various material power laws, damping coefficients, and initial gaps between the microplate and the substrate. The numerical results for various boundary conditions demonstrate that by increasing the damping coefficient, the dynamic pull-in voltage is also increased, and pull-in time will slow down. Moreover, the effect of power law and applied voltage on the pull-in instability is investigated.

- by Amirhossein Moghanian and +1
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- MEMS sensor, Functionally Graded Materials (FGMs) and Porous Media
- by umapathi k
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- MEMS, MEMS sensor

Способите и методите, които са използвани в навигацията през вековете са се променяли, както и съответно целите които обслужват. Един от тези методи е инерциалната навигация. В днешни времена инерциалната навигация предлага много преимущества пред другите типове навигация. Основно преимущество е липсата на зависимост от външни за системата предаватели или други устройства, което означава независимост на системата. С развиването на новите технологии точността на тези системи се увеличава, което увеличава областта им на приложимост. Важен аспект е и намаляването на цената на сензорите, което е предпоставка за приложението им в нови области, където до сега не са били предлагани.

At the present time, micro-electro-mechanical system (MEMS) acceler-ometers seem to provide adequate sensitivity, noise level, and dynamic range to be applicable to earthquake strong-motion acquisition. The current common use of MEMS accelerometers in the modern mobile phone may provide a new means to easily enormously increase the number of observations when a strong earthquake occurs. However, before utilizing the signals recorded by a device, like a mobile phone equipped with a low-cost three-axis MEMS accelerometer for any scientific purpose, it is important to verify that the signal collected provides reliable records of ground motion. In this paper, we have tested the LIS331DLH MEMS accelerometer installed in the iPhone mobile phone using a vibrating table and the EpiSensor FBA (force-balance accelerometer) ES-T as the reference sensor. Our tests show that, in the typical frequency and amplitude range of interest of earthquake engineering (0.2-20 Hz and 10-2000 mg, in which g is the standard gravity of acceleration, or 9:80665 m=s 2), the LIS331DLH MEMS accelerometer has excellent frequency and phase response, comparable with that of some standard FBAs produced for strong-motion seismology. The main drawback of the LIS331DLH MEMS accelerometer is its low sensitivity, due to the high level of instrumental self noise, and so it can be used effectively only to record moderate to strong earthquakes (M L > 5) near the epicentral area.

Documentation and Tutorial on the use of the GY-521 Sensor breakout board. The board consists of a gyroscope and an accelerometer. The tutorial illustrates the interfacing of the sensor board with Arduino and LEDs.

- by Chinonso H Egejuru
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- MEMS sensor, Gyroscope, Accelerometer
- by Peter Hubinsky
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- Mechatronics, MEMS sensor, Mechatronics and Robotics, Mechatronics Engineering
- by Gitesh Mishra
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- MEMS, MEMS sensor

A brief review on the use of acoustic
waves in designing MEMS based resonator is
described in this paper. Acoustic devices can be
further classified into two basic types – Surface
acoustic wave (SAW) and Bulk acoustic wave
(BAW) devices. A BAW resonator is modeled
and simulated using COMSOL Multiphysics 4.3.
In this model variation in thickness and
piezoelectric material is the prime focus for
studying the basic variation in series resonance
and surface deformation of the device.

Advancements in neurotechnologies for electrophysiology, neurochemical sensing, neuromodulation, and optogenetics are revolutionizing scientific understanding of the brain while enabling treatments and preventative measures for a variety of neurological disorders. The grand challenge in neural interface engineering is to seamlessly integrate the interface between neurobiology and engineered technology to record from and modulate neu-rons over chronic timescales. However, the biological inflammatory response to implants, neural degeneration, and long-term material stability diminishes the quality of the interface overtime. Recent advances in functional materials are aimed at engineering solutions for chronic neural interfaces, yet, the development and deployment of neural interfaces designed from novel materials have introduced new challenges that have been largely unad-dressed. Many engineering efforts that solely focus on optimizing individual probe design parameters, such as softness or flexibility, downplay critical multi dimensional interactions between different physical properties of the device that contribute to overall performance and biocompatibility. Moreover, the use of these new materials present substantial new difficulties that must be addressed before regulatory approval for use in human patients is achievable. In this review, the interdependence of different electrode components is highlighted to demonstrate the current material-based challenges facing the field of neural interface engineering.

- by Takashi D Y Kozai and +1
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- Microelectronics And Semiconductor Engineering, Microelectronics, Brain-computer interfaces, Neural Interfacing

La adsorción es un fenómeno que ocurre cuando hay atracción de moléculas de la superficie de un sólido (adsorbente), y las moléculas de un fluido (adsorbato). Si hay interacción de Van der Waals entre las moléculas del adsorbato y la superficie del adsorbente se trata de una adsorción física (fisisorción). Por otro lado si las moléculas adsorbidas reaccionan químicamente con la superficie, a esto se le denomina adsorción química, formando y rompiendo enlaces como consecuencia. El modelo de adsorción descrito por él Isoterma de Langmuir describe la relación de moléculas adsorbidas en una superficie de monocapa de sólido con la presión de un gas o concentración de un medio que se encuentra a una misma temperatura. Él propósito de la siguiente práctica fue estudiar el fenómeno de adsorción del ácido acético en carbón activado, además de la determinación del área superficial del carbón activado aplicando el modelo de Langmuir. Se realizaron soluciones de Carbono activado y ácido acético a distintas concentraciones, se filtraron después de haber reaccionado para poder cuantificar la cantidad de ácido acético adsorbida a la monocapa de carbono por diferencias de concentración. Se obtuvo el comportamiento del número de moles adsorbidos en función de las diferentes concentraciones de equilibrio y posterior a ello se linealizo el modelo. Finalmente se pudo determinar el área de superficie de adsorción con un valor de 318 m 2 / gramo la cual se comparó con los resultados experimentales existentes en la literatura y se ahondo en los factores que pudieran alterar lo reportado.

- by Javier Hernández Aguilar
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- Engineering Physics, Physics, Chemistry, Molecular Biology

Seismology deals with the study of the activity of physical forces responsible for the origin of earthquakes and the seismic waves generated within the Earth. All structures located from the center of the Earth to its surface are the subject of study in this discipline. Seismology therefore pursues the understanding of the Earth’s internal structure and the physical processes that cause earthquakes, resorting to advanced instruments for observation and measurements. This paper presents an overview of important milestones in the seismological field, followed by revolutions in the instrumentation and observation of seismological events.

- by marco.manso@gmail.com Manso and +1
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- Wireless Sensor Networks, Seismology, MEMS sensor, Sensors

Modern Remotely Piloted Aircraft Systems (RPAS) employ a variety of sensors and multi-sensor data fusion techniques to provide advanced functionalities and trusted autonomy in a wide range of mission-essential and safety-critical tasks. In particular, Navigation and Guidance Systems (NGS) for small RPAS require a typical combination of lightweight, compact and inexpensive sensors to satisfy the Required Navigation Performance (RNP) in all flight phases. In this paper, the synergies attainable by the combination of Global Navigation Satellite System (GNSS), Micro-Electromechanical System based Inertial Measurement Unit (MEMS-IMU) and Vision-Based Navigation (VBN) sensors are explored. In case of VBN, an appearance-based navigation technique is adopted and feature extraction/optical flow methods are employed to estimate the navigation parameters during precision approach and landing phases. A key novelty of the proposed approach is the employment of Aircraft Dynamics Models (ADM) augmentation to compensate for the shortcomings of VBN and MEMS-IMU sensors in high-dynamics attitude determination tasks. To obtain the best estimates of Position, Velocity and Attitude (PVA), different sensor combinations are analysed and dynamic Boolean Decision Logics (BDL) are implemented for data selection before the centralised data fusion is accomplished. Various alternatives for data fusion are investigated including a traditional Extended Kalman Filter (EKF) and a more advanced Unscented Kalman Filter (UKF). A novel hybrid controller employing fuzzy logic and Proportional-Integral-Derivative (PID) techniques is implemented to provide effective stabilization and control of pitch and roll angles. After introducing the key mathematical models describing the three NGS architectures: EKF based VBN-IMU-GNSS (VIG) and VBN-IMU-GNSS-ADM (VIGA) and UKF based Enhanced VIGA (EVIGA), the system performances are compared in a small RPAS integration scheme (i.e., AEROSONDE RPAS platform) exploring a representative cross-section of the aircraft operational flight envelope. A dedicated ADM processor (i.e., a local pre-filter) is adopted in the EVIGA architecture to account for the RPAS maneuvering envelope in different flight phases (assisted by a maneuver identification algorithm), in order to extend the ADM validity time across all segments of the RPAS trajectory. Simulation results show that the VIG, VIGA and EVIGA systems are compliant with ICAO requirements for precision approach down to CAT-II. In all other flight phases, the VIGA system shows improvement in PVA data output with respect to the VIG system. The EVIGA system shows the best performance in terms of attitude data accuracy and a significant extension of the ADM validity time is achieved in this configuration.

- by Roberto Sabatini and +1
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- Aerospace Engineering, Computer Vision, Vision Science, Robot Vision

Saggio su interazione uomo macchina, usabilità, valore euristico dell'arte, le più diffuse tecnologie d'interfaccia, mems, gesture recognition. Contiene i seguenti case studies: smart laser scanner, physical motion interface,... more

- by Marco Infussi
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- Human Computer Interaction, Usability, Gesture Studies, MEMS

Seismometers are instruments used to detect and quantify motions on the ground including those generated by quakes and volcano eruptions. The data obtained by seismometers placed on the lunar surface would contain plenty of information that can provide a good insight and increase our understanding of lunar seismology. A Micro Electro Mechanical Systems (MEMS) based seismic sensor was designed which has several advantages over conventional seismic devices such as low weight, low volume, low power consumption and resilience to harsh environment, i:e: space. The sensor was designed so as to provide the required level of sensitivity while conforming to mission constraints. The sensor was designed, fabricated and qualified at the Laboratory for Electro Optics Systems (LEOS), Indian Space Research Organization (ISRO).

- by Suhas EP
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- MEMS, MEMS sensor, Seismic Engineering, Seismic analysis and design

This documents describes a modular hardware platform for inertial measuring unit and its integration into Matlab Simulink. Its purpose is to give students a way to work with real device in an environment which they are familiar with. They can train various methods of signal processing and filtering and they can get familiar with used MEMS gyroscopes and accelerometers.

- by Peter Hubinsky and +1
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- Mechatronics, Matlab, MEMS sensor, Mechatronics and Robotics

Considerable research efforts have been devoted to the development of MEMS sensor packaging based on different material types (ceramic, plastic and metal). In this work, we describe the design, fabrication and test of a metal packaging with high reliability and low cost. The novelty of our research is on the packaging assembly by mechanical interference replacing the expensive plasma welding process that is used commonly in the development of traditional metal packaging.

- by Humber Mec_Precisão and +1
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- Packaging, MEMS sensor, Piezoresistive Force Sensors.

Two multisensor system architectures for navigation and guidance of small Unmanned Aircraft (UA) are presented and compared. The main objective of our research is to design a compact, light and relatively inexpensive system capable of providing the required navigation performance in all phases of flight of small UA, with a special focus on precision approach and landing, where Vision Based Navigation (VBN) techniques can be fully exploited in a multisensor integrated architecture. Various existing techniques for VBN are compared and the Appearance-Based Navigation (ABN) approach is selected for implementation. Feature extraction and optical flow techniques are employed to estimate flight parameters such as roll angle, pitch angle, deviation from the runway centreline and body rates. Additionally, we address the possible synergies of VBN, Global Navigation Satellite System (GNSS) and MEMS-IMU (Micro-Electromechanical System Inertial Measurement Unit) sensors, and the use of Aircraft Dynamics Model (ADM) to provide additional information suitable to compensate for the shortcomings of VBN and MEMS-IMU sensors in high-dynamics attitude determination tasks. An Extended Kalman Filter (EKF) is developed to fuse the information provided by the different sensors and to provide estimates of position, velocity and attitude of the UA platform in real-time. The key mathematical models describing the two architectures i.e., VBN-IMU-GNSS (VIG) system and VIGADM
(VIGA) system are introduced. The first architecture uses VBN and GNSS to augment the MEMS-IMU. The second mode also includes the ADM to provide augmentation of the attitude channel. Simulation of these two modes is carried out and the performances of the two schemes are compared in a small UA integration scheme (i.e.,
AEROSONDE UA platform) exploring a representative cross-section
of this UA operational flight envelope, including high dynamics manoeuvres and CAT-I to CAT-III precision approach tasks. Simulation of the first system architecture (i.e., VIG system) shows that the integrated system can reach position, velocity and attitude accuracies compatible with the Required Navigation Performance (RNP) requirements. Simulation of the VIGA system also show promising results since the achieved attitude accuracy is higher using the VBN-IMU-ADM than using VBN-IMU only. A comparison of VIG and VIGA system is also performed and it shows that the position and attitude accuracy of the proposed VIG and VIGA systems are both compatible with the RNP specified in the various UA flight phases, including precision approach down to CAT-II.

- by Roberto Sabatini
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- MEMS, GPS Applications, Unmanned Aircraft Systems, Aviation

In this paper we presents a MEMS (Micro-electromechanical System) cantilever based humidity sensor for various applications such as environmental monitoring, electronics, agriculture and biomedical fields. The main focus of this paper is to design, simulate and analyze the performance of MEMS based T shaped microcantilevers using different sensing materials such as Al2O3, Porous Silicon and Poly Silicon. The simulation is done through finite element tool and parameters like the maximum induced stress; deflection and sensitivity of the diaphragms have been analyzed using the software INTELLISUITE version 8.7. The change in humidity element is bending of the microcantilever that modifies the measured displacement between the substrate and the microcantilever. This change in displacement gives the measure of amount of water vapor present in that environment. The outcome of these studies can be used to enhance the sensitivity of these devices. Here we observe that the best sensitivity output responses are obtained in the range of 10%RH to 100% RH and also the maximum sensitivity of 21.85 (m/%RH).

- by Nalla Thambi
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- MEMS sensor
- by Hani Tawfik
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- MEMS, MEMS sensor, Inuit, Imu
- by Mehrzad Modarres
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- Renewable Energy, MEMS sensor, MEMS/NEMS, Microfluidics, Bio-MEMS, MEMS

MEMS (Micro Electro-Mechanical Systems) sensors enable a vast range of applications: among others, the use of MEMS accelerometers for seismology related applications has been emerging considerably in the last decade. In this paper, we provide a comprehensive review of the capacitive MEMS accelerometers: from the physical functioning principles, to the details of the technical precautions, and to the manufacturing procedures. We introduce the applications within seismology and earth sciences related disciplines, namely: earthquake observation and seismological studies, seismic surveying and imaging, structural health monitoring of buildings. Moreover, we describe how the use of the miniaturized technologies is revolutionizing these fields and we present some cutting edge applications that, in the very last years, are taking advantage from the use of MEMS sensors, such as rotational seismology and gravity measurements. In a ten-year outlook, the capability of MEMS sensors will certainly improve through the optimization of existing technologies, the development of new materials, and the implementation of innovative production processes. In particular, the next generation of MEMS seismometers could be capable of reaching a noise floor under the lower seismic noise (few tenths of ng/ √ Hz) and expanding the bandwidth towards lower frequencies (∼0.01 Hz).

- by Antonino D'Alessandro
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- Earthquake Engineering, Seismology (Engineering), MEMS sensor, Earthquake

This work investigates suitability of low cost Micro-Electro Mechanical
System (MEMS) sensors in strong motion related studies, particularly
in dense arrays utilized in producing quick shaking intensity
maps. Two types of MEMS sensors (MEMS-5 and MEMS-50) and a
reference sensor are tested under excitations of sweeping waves and
scaled earthquake recordings. Transfer functions and correlation coefficients
are compared. As for earthquake recordings, comparisons are
carried out in terms of basic strong motion parameters and elastic response
of structures that influences the design majors. The performance
of the MEMS-50 sensor is also investigated on free field conditions. Different
sensing characteristics are compared by performing time frequency
analyses of small earthquake ground motion recordings of the
MEMS-50 based accelerometer and of a co-located reference accelerometer.
Test results show that the MEMS-50 sensor is able to record
the mid-frequency dominant strong motion parameters with high correlation,
where the high frequency components of the ground motion
are underestimated. Such a difference in strong motion parameters on
the other hand, does not manifest itself on empirical instrumental intensity
estimations. Strong motion parameters from the reference and
MEMS sensors converge to the same seismic intensity level. Hence a
strong motion network with MEMS-50 sensors could be a modest option
to produce peak ground velocity-based damage impact of an urban
area under large-magnitude earthquake threats in the immediate vicinity.
MEMS-5, which is an upper quality ensemble, is recommended for
wide range of application including peak ground acceleration-based
and peak ground velocity-based rapid shake maps.

- by Gülüm Tanircan
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- MEMS sensor

A detailed process characterization of SML electron beam resist for high-aspect-ratio nanopatterning at high sensitivity is presented. SML contrast curves were generated for methyl isobutyl ketone (MIBK), MIBK/isopropyl alcohol (IPA) (1:3), IPA/water (7:3), n-amyl acetate, xylene, and xylene/methanol (3:1) developers. Using IPA/water developer, the sensitivity of SML was improved considerably and found to be comparable to benchmark polymethylmethacrylate (PMMA) resist without affecting the aspect ratio performance. Employing 30-keV exposures and ultrasonic IPA/water development, an aspect ratio of 9:1 in 50-nm half-pitch dense grating patterns was achieved representing a greater than two times improvement over PMMA. Through demonstration of 25-nm lift-off features, the pattern transfer performance of SML is also addressed.

- by Mohammad Ali Mohammad
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- Electrical Engineering, Polymer Engineering, Physics, MEMS

In a technological spin-off, initial and further business development is a two-stage challenge of survival and growth. Spin-offs’ business development relies on the design and renewal of an adequate business model, effective open innovation, and advanced knowledge management. This study describes the initial and further business development of a successful spin-off, MEMS&Co, through a longitudinal case study. The business model benefited from specific revenue/investments streams from clients and was subsequently supplemented by new business models in novel applications. Open innovation offered a unique outside-in process from universities, suppliers, and research centres and then transformed into an advanced new process. Knowledge management focused on cross-technical knowledge modularity and subsequently on knowledge recombination.

- by Laurent Scaringella
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- Entrepreneurship, Knowledge Management, MEMS, Longitudinal Research

This paper demonstrates a novel optofluidic pressure sensor. Since optofluidics is becoming an emerging technology which combines the advantages of optics and microfluidics, it is used to bring new benefits to traditional pressure sensors. In this study, an external pressure causes deformation on a microring resonator which yields wavelength shift in the resonating. Whole structure is based on polydimethylsiloxane (PDMS) to ensure compatibility with microfluidic chips. Numerical simulations are performed to determine wavelength shift due to applied pressure. Maximum radial displacement of 2.5 μm is observed for an applied pressure of 25 kPa. A sensitivity of 2 nm/kPa is achieved.

- by Vahid Ganjalizadeh
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- MEMS, MEMS sensor, Optofluidics, MEMS and NEMS

ARIANNA is a small-size system, wearable by an operator for his localisation and tracking. Its design stems from the following assumptions: no need of infrastructure for localisation; low cost, no need of warm-up time (e.g. training phases); seamless switch between GPS-denied/available conditions; computational requirements relaxed enough to be hosted in a commercial smartphone. ARIANNA meets these objectives by adopting a novel two-stage approach: the former stage is a conventional tracking process based on Extended Kalman Filter and step detection; the latter is a post-processing in which the errors due to the sensor drifts are estimated and compensated. The system has been extensively tested with various sensors, different operators, in clear and polluted magnetic environments, with good and poor/intermittent GPS, with paths ranging from 300 m to 3 km, each walked with mixed speeds. The results systematically show good and repeatable performance.

- by Enrico de Marinis
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- Radar, Inertial navigation, MEMS sensor, Wearable Inertial Sensors

In this paper, we have studied the sources of error of a low-cost 3-axis MEMS accelerometer by means of Power Spectral Density and Allan Variance techniques. These techniques were applied to the signals acquired from ten identical devices to characterize the variability of the sensor produced by the same manufacturer. Our analysis showed as identically produced accelerometer have somehow variable behavior in particular at low frequency. It is therefore of paramount importance before their use in Inertial Navigation or Earthquakes Monitoring System, a complete characterization of each single sensors.

Abstract This thesis investigates, how placement variations of electronic devices influence the possibility of using sensors integrated in those devices for context recognition. The vast majority of context recognition research assumes well defined, fixed sensor locations. Although this might be acceptable for some application domains (eg in an industrial setting), users, in general, will have a hard time coping with these limitations.

- by Kai Kunze
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- Ubiquitous Computing, MEMS sensor, Activity Recognition, Accelerometers

Recognition of the mode of motion or mode of transit of the user or platform carrying a device is needed in portable navigation, as well as other technological domains. An extensive survey on motion mode recognition approaches is provided in this survey paper. The survey compares and describes motion mode recognition approaches from different viewpoints: usability and convenience, types of devices in terms of setup mounting and data acquisition, various types of sensors used, signal processing methods employed, features extracted, and classification techniques. This paper ends with a quantitative comparison of the performance of motion mode recognition modules developed by researchers in different domains.

- by Mostafa Elhoushi
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- MEMS sensor, Activity Recognition, Human Activity Recognition, Motion Detection

A modern alternative to the positive-tone PMMA resist is the ZEP 520A (Nippon Zeon) brand co-polymer resist, which offers a higher sensitivity and etch durability for electron beam lithography. However, the molecular mechanisms are not entirely understood, and the relative performance of two resists for various process conditions of nanofabrication is not readily predictable. The authors report a thorough experimental comparison of the performance of PMMA 950k and ZEP 520A resists in MIBK:IPA, ZED, and IPA:water developers. Interestingly, ZEP resist performance was found to depend significantly on the developer. ZED developer increases the sensitivity, whereas IPA:water optimizes line edge roughness and conceivably the resolution at the expense of sensitivity. The authors also describe two alternative numerical models, one assuming an enhancement of the main chain scission in ZEP as a result of electronic excitations in side groups, and another without such enhancement. In the second case, the differences in ZEP and PMMA resists performance are attributed to their different interaction with the developers. Using both approaches, the authors parameterize the respective models of ZEP development by fitting numerical results to the experimental resist morphologies, and analyze the outcomes.

- by Mohammad Ali Mohammad and +2
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- Electrical Engineering, Polymer Engineering, Physics, MEMS

The modelling of physical systems is very important phenomena in today's world due to easy understanding of their dynamics. There are several methods to model the physical systems, one of which is the bond graph technique which is the graphical representation of the physical dynamics of the systems. In this paper, we have modelled the heat mechanism of a biomedical baby incubator that is used to keep babies warm and safe from infections. There are four types of heat transfer mechanism in baby incubator which are conduction, convection, evaporation and radiation. In this study, we have modelled the evaporation mechanism through Pseudo bond graph technique using 20-Sim software package. Later on we have designed a PID Controller to control and monitor the characteristics of evaporation. Our simulation results shows that a baby incubator as an open system can be modelled and analysed for better design using bond graph simulations.

International Journal of Smart and Nano Materials, 2011

- by Mikail F Lumentut
- •
- Engineering Physics, Mechanical Engineering, Applied Mathematics, Physics

The objective of this paper is to demonstrate the integration of a MOF thin film on electrostatically actuated microstructures to realize a switch triggered by gas and a sensing algorithm based on amplitude tracking. The devices are based on the nonlinear response of micromachined clamped-clamped beams. The microbeams are coated with a metal-organic framework (MOF), namely HKUST-1, to achieve high sensitivity. The softening and hardening nonlinear behaviors of the microbeams are exploited to demonstrate the ideas. For gas sensing, an amplitude-based tracking algorithm is developed to quantify the captured quantity of gas. Then, a MEMS switch triggered by gas using the nonlinear response of the microbeam is demonstrated. Noise analysis is conducted, which shows that the switch has high stability against thermal noise. The proposed switch is promising for delivering binary sensing information, and also can be used directly to activate useful functionalities, such as alarming.

- by Adam Bouchaala and +2
- •
- Nonlinear dynamics, MEMS sensor, Gas Sensors, Metal Organic Frameworks (MOFs)
- by Laurent Francis
- •
- Materials Engineering, Mechanical Engineering, MEMS, Sensor
- by Subramanian Ramasamy
- •
- MEMS, GPS Applications, Unmanned Aircraft Systems, Aviation
- by Krishna Chaitanya
- •
- Computer Science, MEMS sensor, ZigBee, Pressure

A compact single cell piezoelectric micromachined ultrasound transducer (PMUT) with dual electrodes is designed, fabricated, and used to measure the density of a fluid mixture mimicking the range of human blood density variation. The sensor's novelty lies in its compactness enabled by on device sensing and actuation due to the dual electrodes. The active material used here is thin film PZT which is protected from the fluid environment with an appropriate coating. The results obtained show a linear response of the sensor output over the density range of interest with no appreciable degradation in the signal due to immersion in a fluid. The sensitivity of the sensor is 191 Hz/Kg/m 3. These single cell PMUTs are, therefore, potential candidates for fluid density monitoring in industrial or biomedical applications.

- by Avinandan Mandal
- •
- MEMS sensor, Micromachining, Blood Disorders, Bio Fluid Mechanics

Coronavirus disease 19 (COVID-19) is a virus that spreads through contact with the respiratory droplets of infected persons, so quarantine is mandatory to break the infection chain. This paper proposes a wearable device with the Internet of Things (IoT) integration for real-time monitoring of body temperature the indoor condition via an alert system to the person in quarantine. The alert is transferred when the body thermal exceeds the allowed threshold temperature. Moreover, an algorithm Repetition Spikes Counter (RSC) based on an accelerometer is employed in the role of human activity recognition to realize whether the quarantined person is doing physical exercise or not, for auto-adjustment of threshold temperature. The real-time warning and stored data analysis support the family members/doctors in following and updating the quarantined people’s body temperature behavior in the tele-distance. The experiment includes an M5stickC wearable device, a Microelectromechanical system (MEMS) accelerometer, an infrared thermometer, and a digital temperature sensor equipped with the user’s wrist. The indoor temperature and humidity are measured to restrict the virus spread and supervise the room condition of the person in quarantine. The information is transferred to the cloud via Wi-Fi with Message Queue Telemetry Transport (MQTT) broker. The Bluetooth is integrated as an option for the data transfer from the self-isolated person to the electronic device of a family member in the case of Wi-Fi failed connection. The tested result was obtained from a student in quarantine for 14 days. The designed system successfully monitored the body temperature, exercise activity, and indoor condition of the quarantined person that handy during the Covid-19 pandemic.

- by Minh Long Hoang
- •
- MEMS sensor, Temperature Sensors

We present the design, fabrication and experimental results for a novel air-microfluidic lab-on-a-chip sensor, which measures the mass concentration of airborne particulate matter (PM), such as tobacco smoke or diesel exhaust. The sensor detects PM having aerodynamic diameter (AD) of less than 2.5μm, (PM2.5) directly by measuring the deposited PM on a mass-sensing resonator, at flowrates two orders of magnitude lower than the closest comparable devices. We report on an improved sensor design, new mask-less dispenser-printed SU-8-based bonding process, and recorded sensitivity of our newly-developed design.

- by Omid Mahdavipour and +2
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- Sensors and Sensing, Finite Element Methods, Microfluidics, Lab On A Chip

An Aircraft Dynamics Model (ADM) augmentation scheme for Remotely Piloted Aircraft System (RPAS) navigation and guidance is presented. The proposed ADM virtual sensor is employed in the RPAS navigation system to enhance continuity and accuracy of positioning data in case of Global Navigation Satellite System (GNSS) data degradations/losses, and to improve attitude estimation by vision based sensors and Micro-Electromechanical System Inertial Measurement Unit (MEMS-IMU) sensors. The ADM virtual sensor is essentially a knowledge-based module that predicts RPAS flight dynamics (aircraft trajectory and attitude motion) by employing a rigid body 6-Degree of Freedom (6-DoF) model. Two possible schemes are studied for integration of the ADM module in the aircraft navigation system employing an Extended Kalman Filter (EKF) and an Unscented Kalman Filter (UKF). Additionally, the synergy between the navigation systems and an Avionics-Based Integrity Augmentation (ABIA) module is examined and a sensor-switching framework is proposed to maintain the Required Navigation Performance (RNP) in the event of single and multiple sensor degradations. The ADM performance is assessed through simulation of an RPAS in representative fight operations. Sensitivity analysis of the errors caused by perturbations in the input parameters of the aircraft dynamics is performed to demonstrate the robustness of the proposed approach. Results confirm that the ADM virtual sensor provides improved performance in terms of data accuracy/continuity, and an extension of solution validity time, especially when pre-filtered and employed in conjunction with a UKF.

- by Roberto Sabatini and +1
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- Aerospace Engineering, MEMS, GPS Applications, Nonlinear dynamics

In this paper, the design, fabrication, and characterization of a robust and low-power micro-machined two-dimensional (2-D) wind sensor based on a glass-in-silicon reflow process are presented for the first time. The four thermistors, which act simultaneously as heat sources and as temperature sensors, are placed on a low thermal conductivity glass substrate, and arranged in a Wheatstone bridge configuration supplied with constant voltage. In this self-heated mode, the total power consumption of the sensor could be reduced into the sub-milliwatt range, offering high initial sensitivity and wide measurement range, respectively. The embedded vertical silicon vias in the glass substrate are used to realize the electrical connections between the sensing elements and the electrode-pads, which are respectively placed on the front and the back surface of the chip. Then, the sensor and the external circuit are connected using the wire-bonding process through the electrode-pads on the back surface. The bonding wires at the backside is encapsulated by polyester paint, protecting the electrical connections of the sensor from the effect of the external environment. In addition, a passivation layer of nitride is deposited on the surface of the wind sensor to prevent direct exposure of the sensing elements to harsh media. The sensor was tested in a wind tunnel in constant voltage mode. Measurement results show that the thermal wind sensor can measure wind speeds up to 17.5 m/s, and the measured sensitivities of the sensor with different applied voltages (0.5, 1, 1.5 V) are, respectively 24.9, 148.3 and 440.61 mV/(m/s) at zero-flow point. The corresponding power consumption of the sensor with different voltages are respectively 4.81, 19.23 and 43.27 mW. Measurement results also show that wind direction in a full range of 360° with an err within 6° could be obtained. The proposed sensor can be used for many applications with a low power consumption and high reliability.

- by Yanqing Zhu
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- MEMS sensor, MEMS design: Sensors and Actuators

High sensitivity MEMS pressure sensor chip for different ranges (1 to 60 kPa) utilizing the novel electrical circuit of piezosensitive differential amplifier with negative feedback loop (PDA-NFL) is developed. Pressure sensor chip PDA-NFL utilizes two bipolar-junction transistors (BJT) with vertical n-p-n type structure (V-NPN) and eight piezoresistors (p-type). Both theoretical model of sensor response to pressure and temperature and experimental data are presented. Data confirms the applicability of theoretical model. Introduction of the amplifier allows for decreasing chip size while keeping the same sensitivity as a chip with classic Wheatstone bridge circuit.