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With
gratitude and recognition to our fine sponsors:
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Research Projects ·
Wireless antenna
sensor skin for Structural Health Monitoring ·
Remote
generation and steering of ultrasound using microwave ·
Unpowered wireless
ultrasound/Acoustic Emission sensing ·
Remote-powered wireless strain gauge ·
Smart shoes with embedded shear/pressure sensors for
Diabetic foot diagnosis and ulcer prevention
Wireless antenna sensor skin for Structural Health
Monitoring Human
skin can achieve very high sensitivity and ultra-fine spatial resolution
through dense distribution of diverse sensory receptors. Despite the
tremendous efforts put forth by researchers from various engineering
disciplines, no engineered sensor skin can achieve comparable sensor density,
functionality, and data efficiency as that of human skin. A major challenge
is the wiring and power requirement of the sensor nodes. To address this
challenge, ASTL has invented a new class of wireless sensor based on the
microstrip antenna technology. With integrated sensing and data transmitting
capabilities, these antenna sensors can be remotely integrated without
needing any external wiring. The application of these antenna sensors for
wireless strain sensing and multi-site crack detection has been demonstrated.
The goal of this project is to form distributed,
passive, wireless antenna sensor networks for full-field strain
measurement and crack characterization. This project is supported by the
AFOSR and the NSF CAREER award. Remote generation and steering of ultrasound using microwave Damage detection based on ultrasonic waves is one of the most popular and well-researched non-destructive inspection schemes employed by many structural health monitoring (SHM) systems. Current ultrasound-based SHM technologies rely heavily on wired sensors that are costly to install and maintain. This study focuses on the development of a new class of unpowered wireless ultrasound actuator (UWUA) that can be remotely and selectively excited using microwave. The goal is to realize wireless generation and steering of ultrasound. This project also strives to establish a physics-based mechanical and electrical model of the bonded piezoelectric wafer transducer, which will help understanding the effect of the bonding layer on the transducer. This project is supported by Office of Naval Research (ONR).
Unpowered wireless Acoustic Emission sensing Acoustic Emission (AE) sensing is a passive Structural Heath Monitoring technique that is very sensitive crack generation and propagation. Wireless AE sensors are attractive because the sensing data are transmitted without any electric wiring. However, the state-of-the-art wireless AE sensors do not have sufficient bandwidth and data throughput to transmit the full waveform of AE signals. We are developing a wireless AE sensor that is fundamentally different from mainstream wireless sensors. By implementing a low-power amplifier powered by light or RF interrogation signal, the wireless AE sensor is able to sense and transmit the full waveform of AE signals wirelessly without requiring any local power source. This project is supported by the Texas Ignition Fund and Norman Hackerman Advanced Research Program (NHARP). Remote-powered wireless strain gauge This project studies the implementation and characterization of a wireless strain measurement system that is powered by solar energy or RF energy. This system includes a wireless strain sensor that consumes about 6 mW, a wireless solar energy harvesting unit, and a frequency modulation/demodulation unit. To achieve such an ultra-low power operation, a voltage-controlled oscillator (VCO) is used to convert the direct-current (DC) strain signal to a high frequency oscillatory signal. Next, this oscillatory signal is transmitted by an unpowered wireless transponder. A generic solar panel with energy harvesting circuit is developed to power the strain sensor node. The system features ultra-low power consumption, completely wireless sensing, remote powering, and portability. This system is capable of both dynamic and static structural measurement. Smart shoes for diabetic foot diagnosis
and ulcer prevention A foot ulcer is the initiating factor in 85% of all diabetes amputations. Ulcer formation is believed to be contributed by both pressure and shear forces. However, the interaction of pressure and shear is rarely studied because of the lack of in-shoe shear sensors. We are developing a hybrid antenna sensor that can measure pressure and shear simultaneously and at the same location. These sensors will be embedded in the insole of custom-made shoes to monitor the in-shoe pressure/shear distribution. If successful, the smart shoes will benefit diabetic foot diagnostics and ulcer prevention as well as footwear design for diabetic patients. This project was funded by the Texas Medical Research Collaboration program. ASTL has completed a variety of projects on optical fiber sensors, including LPFG-based whitelight interferometry for arbitrary small distance measurement, hybrid polymer-silica optical fiber strain sensors, light reflectance distance sensors, and tapered optical fiber sensor for refractive index measurement. In addition, we have also studied elastic wave generation using piezoelectric patches. For more details on these completed projects, please see the related publications. |
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First Street, Arlington, TX 76019, Tel: 817-272-0563, Fax: 817-272-5010, Email: huang@uta.edu
Copyright
@2006-2013, University of Texas at Arlington. All rights reserved. Last Updated
02/04/2013.