헤테로코어 광파이버 노출형 센서모듈과 계측 지연현상

송영용,박익태,이환우 한국전산구조공학회 2019 한국전산구조공학회논문집 Vol.32 No.6

The objective of this study is to develop a new type of buried sensor module that can directly assess pre-stressed concrete by measuring strain using a hetero-core optical fiber sensor. In this regard, experiments were conducted to evaluate the performance of the sensor using an exposure sensor module. Based on the experimental results, when the values of the displacement control velocity were 0.12 mm/min and 1.80 mm/min, the corresponding delays in the measurement were 52.1 s and 2.6 s respectively, which indicated that the maximum delay between the two measurements was a factor of 19. Due to the measurement delay phenomena, the sensor module used in the experiments cannot be employed to check the real-time state of the structure. Thus, additional experiments were needed to develop a new sensor module that can measure the real-time state of the structure. To investigate the cause of the measurement delay phenomena, three experiments were conducted. It was confirmed that measurement delay is mainly attributed to frictional resistance. The measurement delay phenomena were not observed in the experiments using the friction-removed device. 본 연구는 헤테로코어 광파이버 센서를 활용하여 콘크리트 내부에서 발생되는 변형률의 측정을 통해 콘크리트의 프리스트레스를 직접 평가할 수 있는 새로운 매립형 센서모듈 개발을 최종 목표로 하고 있다. 이를 위하여 노출형 센서모듈을 이용한 성능발현 실험결과는 가력속도 0.12, 1.80mm/min일 때 52.1, 2.6sec로 최대 약 19배의 계측 지연현상이 발생하였다. 계측 지연현상은 구조물의 실시간 변화 상태를 계측하지 못하는 경우로 실시간 계측이 가능한 센서모듈의 개발을 위해서 추가실험이 필요한 것으로 판단하였다. 계측 지연현상 원인규명 실험은 3가지의 실험을 계획하였으며, 실험결과는 마찰저항에 의한 계측 지연이 지배적으로 확인되었다. 마찰이 제거된 장치를 이용한 센서모듈의 실험결과에서는 계측 지연현상이 나타나지 않은 것으로 확인되었다.

환경정보 모니터링을 위한 헤테로코어형 광파이버 센싱 시스템

김영복(Young Bok Kim),김영배(Young Bae Kim),이환우(Hwan Woo Lee) 한국방재안전학회 2008 한국방재안전학회 논문집 Vol.1 No.3

본 논문에서는 기존 광파이버센서가 갖는 문제점을 보완할 수 있는 새로운 형태의 광파이버센서에 대해 소개한다. 저자 등이 개발한 헤테로코어 광광파이버센서는 비교적 간단하면서도 큰 곡률 반경에 있어서 전달손실이 발생하며 민감한 손실특성을 나타내는 원리를 이용한 것이다. 또한 원리상 온도의존성 이 거의 없어 온도보상이 필요 없고, 마크로벤딩에 의한 광량변화를 검출하는 방식이므로 파단우려가 없는 것도 가장 큰 장점 중의 하나이다. 이러한 특징을 갖는 센서에 대한 내환경특성을 분석하고 평가하기 위해, 본 논문에서는 헤테로코어형 광파이버센서를 이용하여 각종 환경정보를 모니터링하는 광네트워크형 멀티환경 모니터링 시스템을 구성할 경우 고려해야 할 특성에 대해 검토하였다. 즉, 온도변화에 대한 센싱시스템의 강인성을 실험을 통해 확인하였다. 이것은 실용적 관점에서 계측시스템 전체의 환경변화에 대 한 종합적인 평가를 수행하는 것을 의미하며 그 결과를 본 논문에 소개한다. In this paper, we introduce a multi purpose environmental monitoring system developed as a commercially available standard using the technique of hetero-core spliced fiber optic sensor. The monitoring system has been tested and evaluated in a possible outdoor condition in view of the full scaled operation at actual sites to be monitored. Additionally, the developed system in this work conveniently provides us with various options of sensor modules intended for monitoring such physical quantities as displacement, distortion, pressure, binary states, and liquid adhesion. Two channels of optical fiber line were monitored, in each of which three displacement sensor modules were connected in series, in order to examine the performance to a pseudo-cracking experiment in the outdoor situation, and to clarify temperature influences to the system in terms of the coupling of optical connectors and the OTDR stability. The pseudo-cracking experiment successfully observed the actually given cracks by means of calculation based on the detected displacement values and their geometrical arrangement of the used sensor modules. And the robustness to the temperature is verified in the various temperature change.

광파이버 변위 센서를 적용한 자기베어링 정적 부상 제어 연구

강종규,신우철,홍준희 한국공작기계학회 2003 한국공작기계학회 추계학술대회논문집 Vol.2003 No.-

Five expensive sensors are necessary to control a magnetic bearing system. The sensor price rate of magnetic bearing system is high. So it is necessary that cheap and good sensor is developed. The optical fiber displacement sensor is adaptive to satisfy this condition. We can design magnetically suspended spindle based on static characteristic of optical fiber displacement sensor developed. The controller can be designed by decoupled feedback PD. Therefore, it is simpler than any other controller comparatively.

광파이버 센싱기술기반 압력센서장치

김영복(Y. B,Kim) 한국동력기계공학회 2009 한국동력기계공학회 학술대회 논문집 Vol.2009 No.11

An environmental monitoring system has been developed as a commercially available standard using the technique of hetero-core spliced fiber optic sensor, for the purposes of monitoring large scaled structures and preserving natural environments. The developed system in this work conveniently provides us with various options of sensor modules intended to measure such physical quantities as displacement, distortion, pressure, binary states and liquid adhesion. In this paper, the experiment study has been performed to clarify temperature influences to the system in terms of the coupling of optical connectors and the OTDR stability. From the experiment, it has been verified that the sensing system is robust to the temperature change ranging from the general condition to the hard condition. The specification and performances of various option modules including the pressure sensor have been demonstrated to show the capability of inspecting various physical quantities.

헤테로코어형 광파이버 압력센서개발을 위한 기초연구

김영복(Y. B. Kim) 유공압건설기계학회 2010 드라이브·컨트롤 Vol.7 No.2

A new type fiber optic sensing system has been developed as a commercially available standard using the technique of hetero-core spliced fiber optic sensor, for the purposes of monitoring large scaled structures, preserving natural environments and measuring physical phenomenons. The sensing system has been tested and evaluated in a possible outdoor condition in view of the full scaled operation at actual sites to be monitored. Additionally, the developed system in this work conveniently provides us with various options of sensor modules intended to measure such physical quantities as displacement, distortion, pressure, binary states and liquid adhesion. The experiment study has been performed to examine the performance to a pseudo-cracking experiment in the outdoor situation, and to clarify temperature influences to the system in terms of the coupling of optical connectors and the OTDR stability. It has been verified that the sensing system is robust to the temperature change ranging from the general condition to the hard condition. Especially, in this study, the specification and performances of the pressure sensor have been demonstrated to show the capability of inspecting various physical quantities.

프리스트레스 측정을 위한 헤테로코어 광파이버 센서의 분해능 검증 기초실험

박익태,최광수,김태양,이환우 한국전산구조공학회 2018 한국전산구조공학회논문집 Vol.31 No.5

이 실험연구는 PSC 교량의 생애주기 프리스트레스 측정용 헤테로코어 광파이버 센서를 개발하기 위한 선행연구이며, 기존의 헤테로코어 변위센서의 정밀도를 향상하기 위한 실험이다. 실험결과 최대 2μm 단위의 변위 변화량을 측정할 수 있었다. 즉, 변위측정 길이가 30cm의 센서모듈을 설계했을 때 설계기준압축강도(fck)가 40MPa인 경우 0.2MPa 단위의 응력변화를 측정이 가능함을 확인하였다. 따라서 본 실험의 결과는 향후 진행될 내부매립용 센서모듈 개발에 유용한 자료로 활용될 수 있을 것으로 판단된다. This is the study for developing the hetero-core optical fiber sensors which are purpose to measure the prestress of PSC bridges during the life cycle period. The goal of this study is to improve the resolution of hetero-core sensors. As a result of the test, it is possible to measure the displacement in 2μm increments. In other words, if the length of the sensor module is 30cm, it is possible to measure the prestress variations in 0.2MPa increments at specified compressive strength of concrete(fck) of 40MPa by Hook's Law. So it can be useful for development of a sensor module measuring internal prestress measurement.

고속 주축 상태 모니터링용 광파이버 변위 센서 설계 제작 및 성능평가

홍준희,박찬규,신우철,이동주 한국공작기계학회 2004 한국공작기계학회 추계학술대회논문집 Vol.2004 No.-

This paper is focused on practical applicability of the optical fiber sensor considering the machine center which is going to use them. Optical fibers may be fluctuated because the machine center operates as column moving type. This causes distortion of the sensor output signal. To reduce this problem, we have improved the sensor structure and its bracket. And we evaluated performances of the sensor.

고속 주축 상태 모니터링용 광파이버 변위 센서 설계 제작 및 성능평가

홍준희(Jun-hee Hong),박찬규(Chan-gyu Pare),신우철(Woo-cheol Shin),이동주(Dong-ju Lee) 한국생산제조학회 2004 한국생산제조시스템학회 학술발표대회 논문집 Vol.2004 No.10

This paper is focused on practical applicability of the optical fiber sensor considering the machine center which is going to use them. Optical fibers may be fluctuated because the machine center operates as column moving type. This causes distortion of the sensor output signal. To reduce this problem, we have improved the sensor structure and its bracket. And we evaluated performances of the sensor.

자기베어링 모니터링용 광파이버센서의 성능 평가

박한수,정택구,홍준희,이동주 한국공작기계학회 2002 한국공작기계학회 추계학술대회논문집 Vol.2002 No.-

In a high speed spindle system, it is very important to monitor the state of rotating rotor. Particularly in active control spindle system, the position sensor must provide feedback to the control system on the exact position of the rotor. In order to monitor the state of a high speed spindle exactly, high accuracy and wide frequency bandwidth of sensors are important. The focus in this paper is to make a fiber optic sensor for monitoring rotor of magnetic bearing, to design the circuit for detecting optical signal, and to evaluation static and dynamic characteristics of fiber optic sensor.

자기베어링 모니터링용 광파이버센서 개발에 관한 연구

홍준희,한복수 한국공작기계학회 2003 한국생산제조학회지 Vol.12 No.1

In a high speed spindle system, it is very important to monitor the state of rotating rotor. Particularly in active control spindle system, the position sensor must provide feedback to the control system on the exact position of the rotor. In order to monitor the state of a high speed spindle exactly, high accuracy and wide frequency bandwidth of sensors are important. The focus in this paper is to make a fiber optic sensor for monitoring rotor of magnetic bearing to design the circuit for detecting optical signal, and to evaluation static and dynamic characteristics of fiber optic sensor.