Development of a Wireless MEMS Multifunction Sensor System and Field Demonstration of Embedded Sensors for Monitoring Concrete Pavements, TR-637, 2016

Pavements tend to deteriorate with time under repeated traffic and/or environmental loading. By detecting pavement distresses and damage early enough, it is possible for transportation agencies to develop more effective pavement maintenance and rehabilitation programs and thereby achieve significant cost and time savings. The structural health monitoring (SHM) concept can be considered as a systematic method for assessing the structural state of pavement infrastructure systems and documenting their condition. Over the past several years, this process has traditionally been accomplished through the use of wired sensors embedded in bridge and highway pavement. However, the use of wired sensors has limitations for long-term SHM and presents other associated cost and safety concerns. Recently, micro-electromechanical sensors and systems (MEMS) and nano-electromechanical systems (NEMS) have emerged as advanced/smart-sensing technologies with potential for cost-effective and long-term SHM. This two-pronged study evaluated the performance of commercial off-the-shelf (COTS) MEMS sensors embedded in concrete pavement (Final Report Volume I) and developed a wireless MEMS multifunctional sensor system for health monitoring of concrete pavement (Final Report Volume II)

Fake-Acknowledgment Attack on ACK-based Sensor Power Schedule for Remote State Estimation

We consider a class of malicious attacks against remote state estimation. A sensor with limited resources adopts an acknowledgement (ACK)-based online power schedule to improve the remote state estimation performance. A malicious attacker can modify the ACKs from the remote estimator and convey fake information to the sensor. When the capability of the attacker is limited, we propose an attack strategy for the attacker and analyze the corresponding effect on the estimation performance. The possible responses of the sensor are studied and a condition for the sensor to discard ACKs and switch from online schedule to offline schedule is provided.Comment: submitted to IEEE CDC 201

Wireless Sensor Networks for Process Monitoring: The Rise of Remote Control (Editorial)

Wireless sensor networks (WSNs), which are capable of monitoring or controlling the systems to which they are coupled, have seen increased usage in industrial applications over recent years. A WSN consists of multiple ‘nodes’: small, autonomous devices which are inherently resource constrained and must operate for extended periods of time from limited local energy reserves. Nodes typically contain sensors, a microcontroller, radio transceiver, and power supply. The node’s sensors monitor the system to which they are coupled; for example, a node mounted on an electric motor could measure its vibration signature

Investigation of Wireless Sensor Deployed on a Rotating Shaft and Its Potential for Machinery Condition Monitoring

Rotating shafts are the most critical component of rotating machines such as motors, pumps, engines and turbines. Due to their heavy duties, defects are more like developed during operation. There are many techniques used to monitor shaft defects by analysing the vibration of the shaft as well as the instantaneous angular speed (IAS) of the shaft. The signal are measured either using non-contact techniques such as laser-based measurement or indirect measurement such as the vibration on bearing housings. The advancement in low cost and low power Micro Electro Mechanical Systems (MEMS) make it possible to develop an integrated wireless sensor which can be mounted on the shaft. This can make the fault diagnosis of rotating shafts more effective because the sensor can be mounted on the shaft directly. This paper presented a novel integrated wireless accelerometer for rotational parameter measurement. Its performance is benchmarked with that from a shaft encoder. Experimental results show that the wireless acceleration signal has less noise and hence it is more possible for small fault detection. Keywords: Wireless sensor, Rotating shaft, Instantaneous angular speed, Condition monitorin

Interoperability Optimization and Service Enhancement in Vehicle Onboard Infortainment Systems

This paper presents an overview on optimizing interoperability between different applications for enhanced return-on-investment through utilization of business intelligence in conjunction with prognostics and health management methodology. Such implementation is particularly suitable for deployment in mass-produced vehicle onboard diagnostics system

Efficient redundancy in wired and wireless S2A architectures for NCS

This thesis focuses on the integration of wired and wireless nodes running on top of Gigabit Ethernet and WiFi respectively in Networked Control Systems. Such a networked control system investigated in this work consists of two wireless sensors, two wireless actuators, 14 wired sensors, two wired actuators and one wired supervisor. The architecture is based on Sensor-To-Actuator model. It is revealed through OMNeT++ simulations that the wired and wireless packet end-to-end delays in the developed model satisfy system requirements with no packet loss. Moreover, wired, wireless and mixed interferences are studied and quantified. The amount of interference that the model can withstand is determined. All results are subjected to a 95% confidence analysis. Additionally, the thesis focuses on reliability in the design of networked control systems that is becoming greatly important. Fault-tolerance is often used to increase system reliability. In this work, Triple Modular Redundancy (TMR) and Parallel Redundancy Protocol (PRP) are both applied to a Sensor-to-Actuator architecture with 16 sensors, four Actuators and one Supervisor. Two of the 16 sensors as well as two of the four actuators are wireless while the rest of the nodes are wired. It is first shown that this NCS succeeds in meeting all control system requirements (zero packet loss and bounded end-to-end delay). Reliability models are then developed to help designers choose the appropriate mix of fault-tolerant techniques in order to maximize lifetime while at the same time minimizing the extra cost due to the added redundancy

A New Taxonomy for Symbiotic EM Sensors

It is clear that the EM spectrum is now rapidly reaching saturation, especially for frequencies below 10~GHz. Governments, who influence the regulatory authorities around the world, have resorted to auctioning the use of spectrum, in a sense to gauge the importance of a particular user. Billions of USD are being paid for modest bandwidths. The earth observation, astronomy and similar science driven communities cannot compete financially with such a pressure system, so this is where governments have to step in and assess /regulate the situation. It has been a pleasure to see a situation where the communications and broadcast communities have come together to formulate sharing of an important part of the spectrum (roughly, 50 MHz to 800 MHz) in an IEEE standard, IEEE802.22. This standard (known as the "TV White Space Network" (built on lower level standards) shows a way that fixed and mobile users can collaborate in geographically widespread regions, using cognitive radio and geographic databases of users. This White Space (WS) standard is well described in the literature and is not the major topic of this short paper. We wish to extend the idea of the WS concept to include the idea of EM sensors (such as Radar) adopting this approach to spectrum sharing, providing a quantum leap in access to spectrum. We postulate that networks of sensors, using the tools developed by the WS community, can replace and enhance our present set of EM sensors. We first define what Networks of Sensors entail (with some history), and then go on to define, based on a Taxonomy of Symbiosis defined by de Bary\cite{symb}, how these sensors and other users (especially communications) can co-exist. This new taxonomy is important for understanding, and should replace somewhat outdated terminologies from the radar world.Comment: 4 pages, 1 Figur

integrated sensing system for upper limbs in neurologic rehabilitation

Abstract Wearable sensing devices for monitoring physiological parameters have proved their benefits in reducing the recovery time of mobility and in restoring the neuro-cognitive processes underlying the movement of the body. This is particularly evident in neurological patients from trauma or degenerative diseases. This kind of devices are generally wired sensors fixed on flexible supports, with complicated configuration and calibration. The work presented here has the goal to provide the design and implementation of a training system for rehabilitation including seven types of sensors, dedicated areas for data transmission in wireless mode, power management and signal multiplexing

Design and experimentation of a solar power system powering measurement chains in concrete structures strengthened with fiber-reinforced polymer rebars

Aquest treball de fi de grau té com a objectiu explorar la viabilitat d'utilitzar plaques solars per alimentar cadenes de mesura en estructures de formigó enfortides amb barres de polímer reforçat amb fibra (FRP). Els principals objectius són: dur a terme una investigació profunda per entendre el funcionament de cada element que conforma el sistema, valorar diverses alternatives, identificar aspectes a tenir en compte respecte a la configuració del model, dissenyar un sistema d'energia solar a mida i realitzar-hi proves experimentals. L'experiment implica una prova de flexió de 3 punts, on la barra de FRP s’ha sotmès a diferents condicions de càrrega. La mesura de la tensió ha sigut l'objectiu principal, tenint en compte la seva sensibilitat a la temperatura, factors ambientals i variacions de càrrega. La prova revela diferències entre la suspensió de càrrega directa i les suspensions seqüencials, destacant l'impacte de la magnitud de la càrrega, la distribució i la resposta estructural en els valors de deformació. Els resultats han demostrat l'eficàcia dels panells solars per proporcionar energia sostenible per a les cadenes de mesura. L'anàlisi d'alternatives mostra el potencial de l'energia solar en aquests tipus de muntatges i com a conseqüència la possible contribució al desenvolupament sostenible dels sistemes de mesura en el sector de la construccióEste trabajo de fin de grado tiene como objetivo explorar la viabilidad de utilizar placas solares para alimentar cadenas de medida en estructuras de hormigón fortalecidas con barras de polímero reforzado con fibra (FRP). Los principales objetivos son: llevar a cabo una investigación profunda para entender el funcionamiento de cada elemento que conforma el sistema, valorar diversas alternativas, identificar aspectos a tener en cuenta respecto a la configuración del modelo, diseñar un sistema de energía solar a medida y realizar pruebas experimentales. El experimento implica una prueba de flexión de 3 puntos, donde la barra de FRP se ha sometido a distintas condiciones de carga. La medida de la tensión ha sido el principal objetivo, teniendo en cuenta su sensibilidad a la temperatura, factores ambientales y variaciones de carga. La prueba revela diferencias entre una suspensión de carga directa y suspensiones secuenciales, destacando el impacto de la magnitud de la carga, distribución y respuesta estructural en los valores de deformación. Los resultados han demostrado la eficacia de los paneles solares para proporcionar energía sostenible a las cadenas de medida. El análisis de alternativas muestra el potencial de la energía solar en este tipo de montajes y como consecuencia de la posible contribución al desarrollo sostenible de los sistemas de medida en el sector de la construcciónThis final project aims to explore the viability of using solar panels for powering measurement chains in concrete structures reinforced with fiber-reinforced polymer bars (FRP). The main objectives of the thesis are to carry out in-depth research to understand the operation of each element that makes up the system, assess various alternatives, identify aspects to take into account regarding the configuration of the model, design a custom solar energy system and carry out experimental tests. The experiment involves a 3-point bending test, where the FRP rebar has been subjected to different load conditions. The strain measurement has been the primary focus, considering its sensitivity to temperature, environmental factors, and load variations. The test reveals differences between a direct load suspension and sequential suspensions, highlighting the impact of load magnitude, distribution, and structural response on strain values. The results have demonstrated the effectiveness of solar panels in providing sustainable energy for measurement chains. The analysis of alternatives shows the potential of solar energy in this type of set ups and therefore the possible contribution to the sustainable development of measurement systems in the construction secto