An Autonomous and Adaptable Wireless Device for Flood Monitoring

Wireless devices can be used to monitor and record a broad range of phenomena. Their advantages include ease of installation and maintenance and considerable reduction in wiring costs. The addition of battery power and radio communication to such wireless devices can result in a completely The operating environment of monitoring systems is often hostile, due to temperature fluctuations, humidity, electromagnetic noise, and other interfering phenomena. The system should be able to adapt to changing conditions to maintain dependability in its operations This paper presents the case study of adapting a flood detection device to the environmental threat of submersion

BOTDA Sensing Employing a Modified Brillouin Fiber Laser Probe Source

A theoretical and experimental study has been carried out on a tunable dual pump-probe optical source for distributed Brillouin optical time-domain analysis (BOTDA). The developed source exploits a modified Brillouin ring laser technology and is capable of a tuning range of ∼200 MHz without using phase-locked loop or optical sideband generation techniques, and exhibits a linewidth smaller than 2.5 MHz and ∼0.5 mW power. In BOTDA experiments, the proposed source has demonstrated to be an efficient solution enabling distributed sensing over 10 km single mode fiber with a spatial resolution of ∼4 m, and a strain and temperature resolutions of ∼10 μϵ and ∼0.5 °C respectively

Study of injection-locked stabilized, short cavity Brillouin ring laser source design for fiber sensing applications

A new pump-seeded, short-cavity Brillouin ring laser source layout intended for Brillouin sensing applications is showcased, showing increased high maximum output (1.5 mW), a strong linewidth narrowing effect (producing light with a linewidth of 10 kHz) and limited relative intensity noise (RIN ~ −145 dB/Hz), providing an ultranarrow, highly stable BRL source that can also be employed as a pump-probe source for Brillouin optical time-domain analysis (BOTDA) applications

Optical characterization of strain sensing cables for Brillouin optical time domain analysis

Two innovative optical fiber cable layouts designed to improve strain measurement accuracy for Brillouin Optical Time Domain Analysis (BOTDA) sensors through improved strain transfer efficiency are presented and discussed. Swept Wavelength Interferometry (SWI) is used to experimentally evaluate their performance alongside analytical models and numerical simulation through Finite Element Method (FEM). The results show good agreement between the different methods and show that the second sensing cable design presents good features to minimize the mismatch between measured and actual strain. Finally, the strain response of both strain and temperature sensing cables of this design are evaluated, showing that their difference in response is reliable enough to allow temperature compensation

Recent Enhancements to the SmartBrick Structural Health Monitoring Platform

This paper introduces several new developments in the SmartBrick structural health monitoring platform. The system, which has been described in previous papers, provides an extremely low-power, long-term method for remote structural health monitoring. The system is capable of monitoring a diverse range of environmental and structural phenomena, including strain, vibration, tilt, and temperature; and communicating the collected data and any alerts over the GSM cellular infrastructure. The system is completely autonomous and wireless, requiring only its self-contained power and GSM network coverage to operate unattended for five or more years. The emphasis of this paper is on advances made in the third generation of the SmartBrick platform. Highlights include the development of a web interface that facilitates retrieval and visualization of data and remote maintenance and calibration of the system, and additional enhancements made to support dynamic structural monitoring. The paper also includes a survey of recent wireless SHM systems, and a comparison of these solutions with the SmartBrick platform

Structural Health Monitoring of Bridges Using Wireless Sensor Networks

Aging and degradation of transportation infrastructure pose significant safety concerns, especially in light of increased use of these structures. The economic downturn further exacerbates such concerns, especially for critical structures such as bridges, where replacement is infeasible and maintenance and repair are expensive. The US Federal Highway Administration has classified over 25% of the bridges in the United States as either structurally deficient or functionally obsolete, underscoring the importance of structural health monitoring (SHM) to ensure public safety. We give an overview of emerging wireless sensor networks (WSN) for autonomous SHM systems, their application, the power use and sources needed to support autonomy, and the type of communication that allows remote monitoring

An Embedded Wireless System for Remote Monitoring of Bridges

This paper describes an autonomous embedded system for remote monitoring of bridges. Salient features of the system include ultra-low power consumption, wireless communication of data and alerts, and incorporation of embedded sensors that monitor various indicators of the structural health of a bridge, while capturing the state of its surrounding environment. Examples include water level, temperature, vibration, and acoustic emissions. Ease of installation, physical robustness, remote maintenance and calibration, and autonomous data communication make the device a self-contained solution for remote monitoring of structural health. The system addresses shortcomings present in centralized structural health monitoring systems, particularly their reliance on a laptop or handheld computer. The system has been field-tested to verify the accuracy of the collected data and dependability of communication. The sheer volume of data collected, and the regularity of its collection can enable accurate and precise assessment of the health of a bridge, guiding maintenance efforts and providing early warning of potentially dangerous events. In this paper, we present a detailed breakdown of the system\u27s power requirements and the results of the initial field test

A Wireless System for Real-Time Environmental and Structural Monitoring

Accurate real-time monitoring of structural health can result in significant safety improvements, while providing data that can be used to improve design and construction practices. For bridges, monitoring of water level, tilt, displacement, strain, and vibration can provide snapshots of the state of the structure. Real-time measurement and communication of this information can be invaluable in guiding decisions regarding the safety and remaining fatigue life of a bridge. This paper describes the real-time data acquisition, communication, and alerting capabilities of the Flood Frog, an autonomous wireless system for remote monitoring. Battery power and utilization of the GSM cellular network result in a completely wireless system. Coupled with the low cost of the device, the elimination of cables allows deployment in locations where autonomous monitoring is hindered by cost or infeasibility of installation. The first prototype of the system was deployed in Osage Beach, MO in November 2006