• 센서학회지
• /
• 제12권5호
• /
• pp.211-217
• /
• 2003

도로의 중앙에 일정한 간격으로 마그네틱 마커를 설치하고 차량에 자기 센서를 장착하여 차량의 이동에 따른 자기장의 변화를 측정하여 차량의 주행 경로를 인식하는 시스템의 성능을 개선하는 방법을 제안한다. 도로에 설치하는 마그네틱 마커들의 설치비를 절감하기 위하여 마커들 간의 설치간격을 기존의 경우보다 넓혔다. 이를 위하여 마커들의 간격에 따른 자계의 분석을 행하여 적절한 마커들의 간격을 알아내고, 6개 센서들의 배치방법과 신경회로망을 이용한 제어방법을 제안하였다. 자기장 분석, 지자기 소거. 학습패턴 획득, 신경망 학습에 의해 조향 제어기를 구성하고 컴퓨터 주행 시뮬레이션을 통해 제안된 방법에 의한 자율주행 차량의 성능이 개선될 수 있음을 확인하였다.

• 대한전자공학회논문지
• /
• 제22권2호
• /
• pp.1-5
• /
• 1985

본 연구에서는 단일모드 광섬유에서의 온도에 의한 위상변조 현상을 분석하고 단일모드 광섬유 간섭계를 이용한 온도센서를 설계. 제작하여 그 온도특성을 조사하였다. 설계한 fiber-optic온도센서는 Mach-Zehnder 간섭계를 이용한 위상감지형 고감도 센서로서 온도변화는 간섭무의의 이동으로써 측정되어졌다. 간섭계에 의한 측정에서 중요한 문제중의 하나는 온도분만 아니라 모든 피측정 물리량의 변화방향에 따른 간섭무의의 이동갯수와 이동방향을 동시에 측정하는 것이다. 이를 위해 다중모드 광섬유를 이용한 배열 검출기를 제작하여 매우 간편하게 간섭무늬의 이동갯수와 이동방향을 측정하였다.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2000년도 Handout for 2000 Inter. Machine Tool Technical Seminar
• /
• pp.109-115
• /
• 2000

The spindle unit is core parts in high precision machine tools. Diverse static, dynamic and thermal charateristics of spindle unit are needed for special purpose of machine tools. Compromise between those charateristics will be done in concept design phase. High static stiffness at spindle nose may be very important performance for heavy cutting work. High dynamic stiffness is also useful to high precision and high speed machine tools. Improvement of thermal charateristics in spindle lead to high reliability of positioning accuracy. For high speed spindle structure, the design parameter such as, bearing span, diameter, bearing type and arrangement, preload, cooling and lubrication method should be in harmony.

• 한국소음진동공학회논문집
• /
• 제20권12호
• /
• pp.1216-1222
• /
• 2010

Based on the MacDonald's analytic model for the diffracted sound field of a semi-infinite noise barrier, computer simulations were performed for various positions of error microphones for an active noise barrier system. The simulation process also included the effects of floor reflections on both sides of the barrier. The results were also compared with Niu's simulation results and showed a straight line arrangement of sensors and actuators, in the order of primary source, secondary source and error microphone is better than over the top arrangement of the error microphones.

• 한국정밀공학회지
• /
• 제21권5호
• /
• pp.91-98
• /
• 2004

Human uses level difference and time difference to get space information. Therefore this paper shows that method to presume direction of sound source by time difference and to mark presumed position. The position means direction from geometrical center of sensors to the sound source. To get the time difference of microphones input level, we will be explained about arrangement of microphones which used for the sensor to take the sound signal. It is included distance among the 3 microphones and distance between microphones and sound source. Secondly, input signals are transmitted to CPU througth digital process. CPU is used to DSP(Digital Signal Processor) for manage the signal by real time. Finally, the position of sound source is perceived by an explained algorithm in this paper.

• 전기전자학회논문지
• /
• 제22권4호
• /
• pp.922-932
• /
• 2018

방사형 거리 센서는 측량 및 자율 주행에 널리 사용된다. 이러한 센서의 작동 원리 및 적용 방법의 교육이 필요하다. 상용 방사형 거리 센서의 저성능화를 통한 저가화가 계속되고 있지만, 교육 목적으로 사용하기에는 여전히 고가이다. 본 논문에서는 교육용 로봇에 활용할 수 있는 저가의 포토트랜지스터의 방사형 배열을 이용한 물체추적기능을 갖는 거리 센서 모듈을 제안한다. 제안하는 방법은 포토트랜지스터를 180도 범위의 배열로 배치하여 빠르게 움직이는 물체의 위치를 즉시 감지할 수 있으며 서보 모터를 사용한 센서 회전으로 감지 각도 범위를 향상하고 물체를 추적한다. 제안된 센서의 스캔 속도는 상업용 거리 센서보다 50~200배 빨라서 1ms의 제어 루프를 가지는 고성능의 교육용 모바일 로봇에 적용할 수 있다.

• 전기학회논문지
• /
• 제63권3호
• /
• pp.409-413
• /
• 2014

GIS partial discharge that occurred in the UHF band signal is effectively detected by the method to IEC60270 5pc the apparent minimum discharge can be detected over the GIS arrangement of the sensor interior and exterior of the UHF in accordance with the optimized position signal by considering the damping ratio is selected so that the signals can be obtained to be mounted. 362kV, 800kV GIS is installed on the internal and external sensors are UHF band signal attenuation is set by measuring the reference value, but the operation, 170kV case 362kV, 800kV on the basis of the measurement data and to be installed and operated. When 170kV per 1Bay by installing the built-in sensor 1 for detecting a partial discharge signal, But, GIS signal attenuation is large in the case of an internal partial discharge signal is not detected in some cases. Where the attenuation is great UHF signal of the sensor by increasing the quantity of partial discharge signals were acquired to allow relocation. The greater the spacing between the sensor and the sensor is applied simplifies the installation and reduces the cost in terms of maintenance of appropriate optimal position is calculated to detect the partial discharge signal is needed. Thus 170kV GIS signal power attenuation of a partial discharge by measuring the UHF sensor, and by relocating the proper position is calculated in accordance with the sensor signal decay rate and minimize the error of omission in detecting a partial discharge signal was optimized.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2004년도 추계학술대회논문집
• /
• pp.109-114
• /
• 2004

This paper presents a theoretical and experimental study of a non-collocated pair of piezopolymer PVDF sensor and piezoceramic PZT actuator, which are bonded on a cantilever beam, in order to suppress unwanted vibration at the tip of the beam. The PZT actuator patch was bonded near the clamped part and the PVDF sensor, which was triangularly shaped, was bonded on the other part of the beam. This is because the triangular PVDF sensor is known that it can detect the tip velocity of a cantilever beam. Because the arrangement of the sensor and actuator pair is not collocated and overlapped each other, the pair can avoid so called 'the in-plane coupling'. The test beam is made of aluminum with the dimension of $200\times20\times2mm$, and the two PZT5H actuators are both $20\times20\times1mm$ and bonded on the beam out-of-phase, and the PVDF sensor is $178mm\times6mm\times52{\mu}m$. Before control, the sensor-actuator frequency response function is confirmed to have a nice phase response without accumulation in a reasonable frequency range of up to 5000 Hz. Both the DVFB and displacement feedback strategies made the error signal from the tip velocity (or displacement) sensor is transmitted to a power amplifier to operate the PZT actuator (secondary source). Both the control methods attenuate the magnitude of the first two resonances in the error spectrum of about 6-7 dB.

• 한국군사과학기술학회지
• /
• 제17권5호
• /
• pp.591-603
• /
• 2014

In this paper, we have described the characteristics of the Underwater Distributed Sensor Network (UDSN) and proposed the conceptual design guideline by an effectiveness analysis. To perform the effectiveness analysis, we defined an battlefield environment, and then analyzed principal components which compose the UDSN to find out simulation parameters and system constraints. We have chosen a measure of effectiveness based on a target trajectory, which could enhance intuitive understanding about current status, and performed various simulations to reveal critical design parameters in terms of sensor node types, arrangement, cost and combination of detection information.

• 한국소음진동공학회논문집
• /
• 제14권10호
• /
• pp.1007-1014
• /
• 2004

This paper presents a study of low frequencies volume velocity vibration control of a smart panel in order to reduce sound transmission. A distributed piezoelectric quadratically shaped polyvinylidene fluoride (PVDF) polymer film is used as a uniform force actuator and an array of $4\;{\times}\;4$ accelerometer is used as a volume velocity sensor for the implementation of a single-input single-output control system. The theoretical and experimental study of sensor-.actuator frequency response function shows that this sensor-actuator arrangement provides a required strictly positive real frequency response function below about 900 Hz. Direct velocity feedback could therefore be implemented with a limited gain which gives reductions of about 15 dB in vibration level and about 8 dB in acoustic power level at the (1,1) mode of the smart panel. It has been also shown that the shaping error of PVDF actuator could limit the stability and performance of the control system.