• Journal of the Institute of Electronics and Information Engineers
• /
• v.51 no.10
• /
• pp.256-263
• /
• 2014

We have designed and made three kinds of FBG(Fiber Bragg Grating) Acoustic Transducer using Hopper type WDM on the use of recently developed FBG in Korea. The newly designed three kinds of FBG Acoustic Transducer using Hopper type WDM have an excellent merit of practical use with simple structure of sensors arm as well as the merit with existing fiber sensors. It was possible to detect sound waves in the range of 10 Hz to 18 kHz through the newly designed three kinds of FBG Acoustic Transducer and also, possible to detect its signal within the maximum range of 8.6 m by the use of most suitable resonance condition of the transducer. Especially, we can expect the utilization of low-frequency signal detection instead of existing acoustic sensor in the environment of electric noise and inferior condition. Furthermore, they can be developed as the high-sensibility and multi-point signal detection system through the sensor array system.

• Proceedings of the IEEK Conference
• /
• 1998.06a
• /
• pp.573-576
• /
• 1998

In this paper, we devised pulse detection transducer that has non-differential characteristics for pulse detection on chongu arterial. The transducer consist of load cell and driving electronic circuits. Load cell consist of cantilever and two metal film strain gauge. The pressure signal from chongu artery is delivered to load cell using artery rider that attached to cantilever. Therefore the pressure pulse signal can obtain by the developed transducer. As the results of experiment, the developed transducer has a good linearity at pressure to voltage conversion and acan detect non-differential pulse signal from chongu artery.

• Proceedings of the KIPE Conference
• /
• 1998.07a
• /
• pp.328-331
• /
• 1998

Because of the powerful tolerance of overload, dynamic response and anti-erosion, Reluctive Pressure Transducer(RPT), as a measuring element of oil pressure equipment is applied to the measuring system of vessels, air craft. The Electrical reluctance appeared in the pressed diaphragm. To process the reluctance as a electric signal, bridge circuit is used. The design using the reluctance of pressure sensor is described in this paper. For the high efficiency of the sensitive RPT, pressure sensor structure is presented and electrical signal processing is simulated.

• Journal of Sensor Science and Technology
• /
• v.27 no.6
• /
• pp.374-379
• /
• 2018

The piezocomposite transducer is widely used because it is highly efficient in transforming electric energy into mechanical energy, and its frequency range is broader than that of other types of ultrasound transducers. A general piezocomposite transducer is composed of an acoustic lens, impedance matching layers, piezoelectric materials, and backing layers. When an input voltage is applied to a piezoelectric material as an active material, it generates sound waves while vibrating. At that time, an impedance matching layer helps the sound waves to propagate forward while reducing the impedance mismatch that may occur at the interface between the active material and its front material. The impedance mismatch has a negative effect on the signal of an ultrasound transducer; thus, it is important to design a matching layer to overcome the issue. In this study, an optimized feature of a matching layer with gradient properties is studied. An objective function is defined to minimize both the average and the deviation of the reflection coefficients that are functions of the frequencies. As a result, an improvement in the signal characteristics with respect to the sensitivity and bandwidth is reported.

• Journal of Institute of Control, Robotics and Systems
• /
• v.9 no.12
• /
• pp.1019-1025
• /
• 2003

We introduce a new auto-calibration/simulation method for a strain gage type transducer/signal-conditioner which guarantees the output linearity and compensates the error automatically. We design a micro voltage supply which is able to interface either AC or DC type excitation voltage. A new strain gage simulator is also designed. We make linearity output of the signal conditioner and can compensate error automatically with this new auto calibration/simulation method. The experimental results show that the error between the real value and the expected one is less than 1%.

• Journal of the Korean Society for Precision Engineering
• /
• v.11 no.2
• /
• pp.32-40
• /
• 1994

In this study by using EMAT(electro magnetic acoustic transducer)the artificial slit is installed on 12B-SUS pipe test piece. By making 4 cycle SH-burst (EMA) incidence to 45 .deg. angle, the signal data of pulse, received from EMAT are translated into digital-signal-processing- method SSP(Split Spectrum Processing) and Deconvolution method. The main conclusions obtained are as follows; (1) the signal data received from EMAT are translated with digital signal proc- essing of SSP-method and Deconvolution-method and this method shows exellent results more than Ultrasonic testing method does; (2) noise can well be removed by SSP with signal data, and resolution and S/N ratio are advanced; (3) when used with Ultrasonic wave general stainless steel has proporties of multiscattering and reflection phenomena, but resolution is progressed by using Deconvolution method;and (4) as addition-averaging-processing mumber is increasing, the resolution and S/N ratio are improved and the satisfactory signal is obtained.

• 한국생물공학회:학술대회논문집
• /
• 2000.11a
• /
• pp.105-110
• /
• 2000

Biosensors consist principally of two basic components, receptor and transducer. The transducer part of the sensor serves the signal transfer from the output domain of the recognition system. Optical method of transducer have many benefits, based on phenomena like emission and absorption. This paper will review the methode of optical transduction in brief and out some new development.

• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.11 no.1
• /
• pp.63-71
• /
• 2017

In this paper, a signal processing circuit for semi-implantable middle ear hearing device is designed using the TCBT which is recently proposed for a new middle ear transducer that can be implanted at round window of cochlea. The designed semi-implantable hearing device transmits digital sound signal from external device located at behind the ear to the internal device implanted under the skin using inductive coupling link methods with high efficiency. The coils and signal processing circuits are designed and implemented considering the total transmission and reception distance including skin thickness of temporal bone for the semi-implantable hearing device. And also, to improve the data transmission efficiency, the output circuits which can supply sufficient signal power is designed. In order to confirm operation of semi-implantable hearing device using inductive coupling link, the circuit analysis was performed using PSpice, and the performance was verified by implementing a signal processing board of an available size.

• Journal of Biomedical Engineering Research
• /
• v.10 no.3
• /
• pp.229-236
• /
• 1989

This paper describes an idea of design and construction for a radial pulse wave detector, In acquiring arterial pulse signal noninvasively, a new combinational fiber-optic transducer was used which has a detecting part and a sensing part. The mechanism of detecting part is composed of special form of structure that can detect changing pulses in contact with skin, and transmits arterial wall movements to the sensing part. It consists of elastic reflector and optical fibers, which are arranged in a fiber pair. Then, the intensity of the reflected light will be proportional to the displacement changed by inclined reflector. Using this transducer, it expected to make a clinically useful tool for arterial pulse wave diagnosis, especially on the application of "MACK- CHIN" in the field of Korean traditional medicine, since : his transducer has a simple structure and has an easy and clear signal acquisition method.on method.

• Proceedings of the KIEE Conference
• /
• 1988.07a
• /
• pp.806-809
• /
• 1988

The frequency response characteristics of a bimorph type PZT piezoelectric transducer was investigated. In this study, function generator which generates short burst signal, plane reflection plate and oscilloscope were used to measure the characteristics of piezoceramic ultrasonic transducer. The resonant frequency of a bimorph type piezoceramic transducer which is acquired by using Tone-Burst Method had good agreement with the measured results from spectrum analyzer.