The Experts below are selected from a list of 30357 Experts worldwide ranked by ideXlab platform
Liang Cheng - One of the best experts on this subject based on the ideXlab platform.
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Sandwich node architecture for agile wireless Sensor networks for real-time structural health monitoring applications
Sensors and Smart Structures Technologies for Civil Mechanical and Aerospace Systems 2012, 2012Co-Authors: Zi Wang, Shamim N. Pakzad, Liang ChengAbstract:In recent years, wireless Sensor network (WSN), as a powerful tool, has been widely applied to structural health monitoring (SHM) due to its low cost of deployment. Several commercial hardware platforms of wireless Sensor networks (WSN) have been developed and used for structural monitoring applications [1,2]. A typical design of a node includes a Sensor Board and a mote connected to it. Sensing units, analog filters and analog-to-digital converters (ADCs) are integrated on the Sensor Board and the mote consists of a microcontroller and a wireless transceiver. Generally, there are a set of Sensor Boards compatible with the same model of mote and the selection of the Sensor Board depends on the specific applications. A WSN system based on this node lacks the capability of interrupting its scheduled task to start a higher priority task. This shortcoming is rooted in the hardware architecture of the node. The proposed sandwich-node architecture is designed to remedy the shortcomings of the existing one for task preemption. A sandwich node is composed of a Sensor Board and two motes. The first mote is dedicated to managing the Sensor Board and processing acquired data. The second mote controls the first mote via commands. A prototype has been implemented using Imote2 and verified by an emulation in which one mote is triggered by a remote base station and then preempts the running task at the other mote for handling an emergency event.
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Sandwich Node Architecture for Task Preemption in Wireless Sensor Networks for Structural Health Monitoring Applications
Structural Health Monitoring-an International Journal, 2011Co-Authors: Zi Wang, Shamim N. Pakzad, Liang ChengAbstract:In recent years, several hardware platforms of wireless Sensor networks (WSN) have been developed and used for structural monitoring applications [1,2]. A typical design of a node includes a Sensor Board and a mote connected to it. Sensing units, analog filters and analog-to-digital converters (ADCs) are integrated on the Sensor Board and the mote consists of a microcontroller and a wireless transceiver. A WSN system based on this node lacks the capability of interrupting its scheduled task to start a higher priority task. This shortcoming is rooted in the hardware architecture of the node. The proposed sandwich-node architecture is designed to remedy the shortcomings of the existing one for task preemption. A prototype has been implemented using Imote2 and verified by an emulation in which one mote is triggered by a remote base station and then preempts the running task at the other mote for handling an emergency event.
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Validation of a Wireless Sensor Network using Local Damage Detection algorithm for Beam-Column Connections
Sensors and Smart Structures Technologies for Civil Mechanical and Aerospace Systems 2010, 2010Co-Authors: Shamim N. Pakzad, Siavash Dorvash, Elizabeth L. Labuz, Minwoo Chang, Liang ChengAbstract:There has been a rapid advancement in wireless Sensor network (WSN) technology in the past decade and its application in structural monitoring has been the focus of several research projects. The evaluation of the newly developed hardware platform and software system is an important aspect of such research efforts. Although much of this evaluation is done in the laboratories and using generic signal processing techniques, it is important to validate the system for its intended application as well. In this paper the performance of a newly developed accelerometer Sensor Board is evaluated by using the data from a beam-column connection specimen with a local damage detection algorithm. The Sensor Board is a part of a wireless node that consists of the Imote2 control/communication unit and an advanced antenna for improved connectivity. A scaled specimen of a steel beam-column connection is constructed in ATLSS center at Lehigh University and densely instrumented by synchronized networked systems of both traditional piezoelectric and wireless Sensors. The column ends of the test specimen have fixed connections, and the beam cantilevers from the centerline of the column. The specimen is subjected to harmonic excitations in several test runs and its acceleration response is collected by both systems. The collected data is then used to estimate two sets of system influence coefficients with the wired one as the reference baseline. The performance of the WSN is evaluated by comparing the quality of the influence coefficients and the rate of convergence of the estimated parameters.
Zi Wang - One of the best experts on this subject based on the ideXlab platform.
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Sandwich node architecture for agile wireless Sensor networks for real-time structural health monitoring applications
Sensors and Smart Structures Technologies for Civil Mechanical and Aerospace Systems 2012, 2012Co-Authors: Zi Wang, Shamim N. Pakzad, Liang ChengAbstract:In recent years, wireless Sensor network (WSN), as a powerful tool, has been widely applied to structural health monitoring (SHM) due to its low cost of deployment. Several commercial hardware platforms of wireless Sensor networks (WSN) have been developed and used for structural monitoring applications [1,2]. A typical design of a node includes a Sensor Board and a mote connected to it. Sensing units, analog filters and analog-to-digital converters (ADCs) are integrated on the Sensor Board and the mote consists of a microcontroller and a wireless transceiver. Generally, there are a set of Sensor Boards compatible with the same model of mote and the selection of the Sensor Board depends on the specific applications. A WSN system based on this node lacks the capability of interrupting its scheduled task to start a higher priority task. This shortcoming is rooted in the hardware architecture of the node. The proposed sandwich-node architecture is designed to remedy the shortcomings of the existing one for task preemption. A sandwich node is composed of a Sensor Board and two motes. The first mote is dedicated to managing the Sensor Board and processing acquired data. The second mote controls the first mote via commands. A prototype has been implemented using Imote2 and verified by an emulation in which one mote is triggered by a remote base station and then preempts the running task at the other mote for handling an emergency event.
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Sandwich Node Architecture for Task Preemption in Wireless Sensor Networks for Structural Health Monitoring Applications
Structural Health Monitoring-an International Journal, 2011Co-Authors: Zi Wang, Shamim N. Pakzad, Liang ChengAbstract:In recent years, several hardware platforms of wireless Sensor networks (WSN) have been developed and used for structural monitoring applications [1,2]. A typical design of a node includes a Sensor Board and a mote connected to it. Sensing units, analog filters and analog-to-digital converters (ADCs) are integrated on the Sensor Board and the mote consists of a microcontroller and a wireless transceiver. A WSN system based on this node lacks the capability of interrupting its scheduled task to start a higher priority task. This shortcoming is rooted in the hardware architecture of the node. The proposed sandwich-node architecture is designed to remedy the shortcomings of the existing one for task preemption. A prototype has been implemented using Imote2 and verified by an emulation in which one mote is triggered by a remote base station and then preempts the running task at the other mote for handling an emergency event.
Bingwen Wang - One of the best experts on this subject based on the ideXlab platform.
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a wireless Sensor network based structural health monitoring system for highway bridges
Computer-aided Civil and Infrastructure Engineering, 2013Co-Authors: Xiaoya Hu, Bingwen Wang, Han JiAbstract:An integrated structural health monitoring (SHM) system for highway bridges is presented in this article. The system described is based on a customized wireless Sensor network platform with a flexible design that provides a variety of Sensors that are typical to SHM. These Sensors include accelerometers, strain gauges, and temperature Sensors with ultra-low power consumption. A S-Mote node, an acceleration Sensor Board, and a strain Sensor Board are developed to satisfy the requirements of bridge structural monitoring. The article discusses how communication software components are integrated within TinyOS operating system to provide a flexible software platform whereas the data processing software performs analysis of acceleration, dynamic displacement, and dynamic strain data. The prototype system comprises a nearly linear multi-hop topology and is deployed on an in-service highway bridge. Data acquired from the system are used to examine network performance and to help evaluate the state of the bridge. Experimental results presented in the article show that the system enables continuous or regular interval monitoring for in-service highway bridges.
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A Wireless Sensor Network‐Based Structural Health Monitoring System for Highway Bridges
Computer-Aided Civil and Infrastructure Engineering, 2012Co-Authors: Bingwen WangAbstract:An integrated structural health monitoring (SHM) system for highway bridges is presented in this article. The system described is based on a customized wireless Sensor network platform with a flexible design that provides a variety of Sensors that are typical to SHM. These Sensors include accelerometers, strain gauges, and temperature Sensors with ultra-low power consumption. A S-Mote node, an acceleration Sensor Board, and a strain Sensor Board are developed to satisfy the requirements of bridge structural monitoring. The article discusses how communication software components are integrated within TinyOS operating system to provide a flexible software platform whereas the data processing software performs analysis of acceleration, dynamic displacement, and dynamic strain data. The prototype system comprises a nearly linear multi-hop topology and is deployed on an in-service highway bridge. Data acquired from the system are used to examine network performance and to help evaluate the state of the bridge. Experimental results presented in the article show that the system enables continuous or regular interval monitoring for in-service highway bridges.
Shamim N. Pakzad - One of the best experts on this subject based on the ideXlab platform.
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Sandwich node architecture for agile wireless Sensor networks for real-time structural health monitoring applications
Sensors and Smart Structures Technologies for Civil Mechanical and Aerospace Systems 2012, 2012Co-Authors: Zi Wang, Shamim N. Pakzad, Liang ChengAbstract:In recent years, wireless Sensor network (WSN), as a powerful tool, has been widely applied to structural health monitoring (SHM) due to its low cost of deployment. Several commercial hardware platforms of wireless Sensor networks (WSN) have been developed and used for structural monitoring applications [1,2]. A typical design of a node includes a Sensor Board and a mote connected to it. Sensing units, analog filters and analog-to-digital converters (ADCs) are integrated on the Sensor Board and the mote consists of a microcontroller and a wireless transceiver. Generally, there are a set of Sensor Boards compatible with the same model of mote and the selection of the Sensor Board depends on the specific applications. A WSN system based on this node lacks the capability of interrupting its scheduled task to start a higher priority task. This shortcoming is rooted in the hardware architecture of the node. The proposed sandwich-node architecture is designed to remedy the shortcomings of the existing one for task preemption. A sandwich node is composed of a Sensor Board and two motes. The first mote is dedicated to managing the Sensor Board and processing acquired data. The second mote controls the first mote via commands. A prototype has been implemented using Imote2 and verified by an emulation in which one mote is triggered by a remote base station and then preempts the running task at the other mote for handling an emergency event.
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Sandwich Node Architecture for Task Preemption in Wireless Sensor Networks for Structural Health Monitoring Applications
Structural Health Monitoring-an International Journal, 2011Co-Authors: Zi Wang, Shamim N. Pakzad, Liang ChengAbstract:In recent years, several hardware platforms of wireless Sensor networks (WSN) have been developed and used for structural monitoring applications [1,2]. A typical design of a node includes a Sensor Board and a mote connected to it. Sensing units, analog filters and analog-to-digital converters (ADCs) are integrated on the Sensor Board and the mote consists of a microcontroller and a wireless transceiver. A WSN system based on this node lacks the capability of interrupting its scheduled task to start a higher priority task. This shortcoming is rooted in the hardware architecture of the node. The proposed sandwich-node architecture is designed to remedy the shortcomings of the existing one for task preemption. A prototype has been implemented using Imote2 and verified by an emulation in which one mote is triggered by a remote base station and then preempts the running task at the other mote for handling an emergency event.
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Validation of a Wireless Sensor Network using Local Damage Detection algorithm for Beam-Column Connections
Sensors and Smart Structures Technologies for Civil Mechanical and Aerospace Systems 2010, 2010Co-Authors: Shamim N. Pakzad, Siavash Dorvash, Elizabeth L. Labuz, Minwoo Chang, Liang ChengAbstract:There has been a rapid advancement in wireless Sensor network (WSN) technology in the past decade and its application in structural monitoring has been the focus of several research projects. The evaluation of the newly developed hardware platform and software system is an important aspect of such research efforts. Although much of this evaluation is done in the laboratories and using generic signal processing techniques, it is important to validate the system for its intended application as well. In this paper the performance of a newly developed accelerometer Sensor Board is evaluated by using the data from a beam-column connection specimen with a local damage detection algorithm. The Sensor Board is a part of a wireless node that consists of the Imote2 control/communication unit and an advanced antenna for improved connectivity. A scaled specimen of a steel beam-column connection is constructed in ATLSS center at Lehigh University and densely instrumented by synchronized networked systems of both traditional piezoelectric and wireless Sensors. The column ends of the test specimen have fixed connections, and the beam cantilevers from the centerline of the column. The specimen is subjected to harmonic excitations in several test runs and its acceleration response is collected by both systems. The collected data is then used to estimate two sets of system influence coefficients with the wired one as the reference baseline. The performance of the WSN is evaluated by comparing the quality of the influence coefficients and the rate of convergence of the estimated parameters.
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Development and deployment of large scale wireless Sensor network on a long-span bridge
Smart Structures and Systems, 2010Co-Authors: Shamim N. PakzadAbstract:Testing and validation processes are critical tasks in developing a new hardware platform based on a new technology. This paper describes a series of experiments to evaluate the performance of a newly developed MEMS-based wireless Sensor node as part of a wireless Sensor network (WSN). The Sensor node consists of a Sensor Board with four accelerometers, a thermometer and filtering and digitization units, and a MICAz mote for control, local computation and communication. The experiments include calibration and linearity tests for all Sensor channels on the Sensor Boards, dynamic range tests to evaluate their performance when subjected to varying excitation, noise characteristic tests to quantify the noise floor of the Sensor Board, and temperature tests to study the behavior of the Sensors under changing temperature profiles. The paper also describes a large-scale deployment of the WSN on a long-span suspension bridge, which lasted over three months and continuously collected ambient vibration and temperature data on the bridge. Statistical modal properties of a bridge tower are presented and compared with similar estimates from a previous deployment of Sensors on the bridge and finite element models.
Simon Laflamme - One of the best experts on this subject based on the ideXlab platform.
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development of wireless Sensor node hardware for large area capacitive strain monitoring
Smart Materials and Structures, 2019Co-Authors: Jong-hyun Jeong, Xiangxiong Kong, William Collins, Caroline Bennett, Simon LaflammeAbstract:Conventional resistive-type strain sensing methods have limitations in large-area sensing due to their relatively small size. The soft elastomeric capacitive (SEC) Sensor is a capacitance-based stretchable electronic strain Sensor, which has shown distinct advantages for mesoscale sensing over conventional strain-based structural health monitoring (SHM) due to its wide surface coverage capability. While recent advances in wireless Sensor technologies have provided an attractive alternative to wired and centralized SHM, the capacitive strain sensing methods have not benefitted from the wireless approaches due to the lack of appropriate hardware element. This study develops a wireless Sensor Board to use the SEC Sensor in combination with a wireless Sensor network for SHM by addressing key implementation challenges. An alternating current (AC)-based De-Sauty Wheatstone bridge circuit is employed, converting dynamic capacitance variation from the SEC Sensor into analog voltage signal. A high-precision bridge balancer and two-step signal amplifiers are implemented to effectively apply for low-level structural strain vibrations. An amplitude modulation-demodulator has been designed to extract the baseband signal (i.e. strain signal) from the carrier signal (i.e. AC excitation for the Wheatstone bridge). And a dual-step shunt calibrator has been proposed to remove the parasitic capacitance effect of lead wires during on-Board calibration process. The performances of the Sensor Board developed in this study have been validated via a series of lab tests, outperforming a conventional wired capacitance measurement system.
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Capacitance-based wireless strain Sensor development
Sensors and Smart Structures Technologies for Civil Mechanical and Aerospace Systems 2018, 2018Co-Authors: Jong-hyun Jeong, Xiangxiong Kong, William Collins, Caroline Bennett, Simon LaflammeAbstract:A capacitance based large-area electronics strain Sensor, termed soft elastomeric capacitor (SEC) has shown various advantages in infrastructure sensing. The ability to cover large area enables to reflect mesoscale structural deformation, highly stretchable, easy to fabricate and low-cost feature allow full-scale field application for civil structure. As continuing efforts to realize full-scale civil infrastructure monitoring, in this study, new Sensor Board has been developed to implement the capacitive strain sensing capability into wireless Sensor networks. The SEC has extremely low-level capacitance changes as responses to structural deformation; hence it requires high-gain and low-noise performance. For these requirements, AC (alternating current) based Wheatstone bridge circuit has been developed in combination a bridge balancer, two-step amplifiers, AM-demodulation, and series of filtering circuits to convert low-level capacitance changes to readable analog voltages. The new Sensor Board has been designed to work with the wireless platform that uses Illinois Structural Health Monitoring Project (ISHMP) wireless sensing software Toolsuite and allow 16bit lownoise data acquisition. The performances of new wireless capacitive strain Sensor have been validated series of laboratory calibration tests. An example application for fatigue crack monitoring is also presented.
