• 제목/요약/키워드: camera vibration

검색결과 239건 처리시간 0.027초

팬.틸트 카메라의 저 진동 마이크로스텝핑 제어기 설계 (Design of a Low-Vibration Micro-Stepping Controller for Pan-Tilt Camera)

  • 유종원;김정한
    • 한국정밀공학회지
    • /
    • 제27권9호
    • /
    • pp.43-51
    • /
    • 2010
  • Speed, accuracy and smoothness are the important properties of pan-tilt camera. In the case of a high ratio zoom lens system, low vibration characteristic is a crucial point in driving pan-tilt mechanism. In this paper, a novel micro-stepping controller with a function of reducing vibration was designed using field programmable gate arrays (FPGA) technology for high zoom ratio pan-tilt camera. The proposed variable reference current (VRC) control scheme reduces vibration decently and optimizing coil current in order to prevent the step motor from occurring missing steps. By employing VRC control scheme, the vibration in low speed could be significantly minimized. The proposed controller can also make very high speed of 378kpps micro-step driving, and increase maximum acceleration in motion profiles.

소형위성용 구경 120mm 지구관측카메라의 진동시험 (Vibration test of 120mm aperture sized earth imaging camera for small satellite)

  • 강명석;최영완;양승욱;김종운;김홍배;임종민
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2006년도 춘계학술대회논문집
    • /
    • pp.686-689
    • /
    • 2006
  • SAC is earth observation camera being developed by satrec initiative. It provides 10m in multi-spectral channel and 50km swath width at 685km altitude. The EQM of SAC has been developed and tested. In this paper, the procedure and result of the vibration test of SAC to validate structural design and to verify structural toughness are described.

  • PDF

카메라를 이용한 구조물의 동특성 추출 (Modal Parameter Extraction Using a Digital Camera)

  • 김병화
    • 한국소음진동공학회논문집
    • /
    • 제18권12호
    • /
    • pp.1229-1236
    • /
    • 2008
  • A set of modal parameters of a stay-cable have been extracted fi:on a moving picture captured by a digital camera supported by shaking hands. It is hard to identify the center of targets attached on the cable surface from the blurred cable motion image, because of the high speed motion of cable, low sampling frequency of camera, and the shaking effect of camera. This study proposes a multi-template matching algorithm to resolve such difficulties. In addition, a sensitivity-based system identification algorithm is introduced to extract the natural frequencies and damping ratios from the ambient cable vibration data. Three sets of vibration tests are conducted to examine the validity of the proposed algorithms. The results show that the proposed technique is pretty feasible for extracting modal parameters from the severely shaking motion pictures.

카메라 흔들림 보정을 통한 증기 누설 탐지 (Detecting steam leakage by using correction of camera vibrating)

  • 최영철;윤찬훈;김진섭
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2014년도 추계학술대회 논문집
    • /
    • pp.394-398
    • /
    • 2014
  • Steam leakage is one of the major issues for the structural fracture of pipes of nuclear power plants. Therefore a method to inspect a large area of piping systems quickly and accurately is needed. Recently, the research detecting the steam leakage by using camera image is introduced. However, this method has a disadvantage. If a camera oscillates, it cannot detect a steam leakage exactly. In this paper, the technique that reduces the error due to a camera shaking is proposed. To verify the proposed method, we have performed the experiments for the oil leakage experiments. The results show that the technique can calibrate the error due to camera shaking.

  • PDF

영상을 이용한 누설탐지에서 카메라 진동 오차 보정 (Correction of Error due to Camera Vibrating During Detecting Steam Leakage by Using Image)

  • 최영철;전형섭;손기성;박종원
    • 한국소음진동공학회논문집
    • /
    • 제24권10호
    • /
    • pp.795-801
    • /
    • 2014
  • Steam leakage is one of the major issues for the structural fracture of pipes of nuclear power plants. Therefore a method to inspect a large area of piping systems quickly and accurately is needed. Recently, the research detecting the steam leakage by using camera image is introduced. However, this method has a disadvantage. If a camera oscillates, it cannot detect a steam leakage exactly. In this paper, the technique that reduces the error due to a camera shaking is proposed. To verify the proposed method, we have performed the experiments for the oil leakage experiments. The results show that the technique can calibrate the error due to camera shaking.

카메라 영상을 이용한 진동변위 측정 시 측정해상도 향상 기법 (Enhancement of Displacement Resolution of Vibration Data Measured by using Camera Images)

  • 손기성;전형섭;한순우;박종원
    • 한국소음진동공학회논문집
    • /
    • 제24권9호
    • /
    • pp.716-723
    • /
    • 2014
  • Vibration measurement using image processing is a fully non-contact measurement method and has many application fields. The resolution of vibration data measured by image processing depends on the camera performance and is lower than that measured by accelerometers. This work discusses the method to increase resolution of vibration signal measured by image processing based on the image mosaic technique with a high-power lens. The working principle of resolution enhancement was explained theoretically and verified by several experiments. It was shown that the proposed method can measure vibrations of relatively large scale structures with increased resolutions.

위성광학탑재체 개발을 위한 나노급 방진장치 개념 설계 (Concept Design of Vibration Isolation System for Development of Optical Payload of Satellite)

  • 이상훈;조혁진;서희준;김영기;문귀원;문상무;김홍배
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2005년도 춘계학술대회논문집
    • /
    • pp.949-952
    • /
    • 2005
  • According to the national space program in Korea, is satellites will be launch into space up to 2015. Especially, KARI is going to develope of its own a high resolution camera of less than 1m to be mounted on next Multipurpose Satellite. When performing testing of large spacecraft or hardware that will be launched into orbit, it is necessary to conduct a testing with space-simulated environment. To achieve this requirement, thermal vacuum chamber is generally used. KARI has been developed a very Large Thermal Vacuum Chamber(LTVC) from 2003 to accomodate future space program, such as KOMPSAT, COMS, and Launch vehicles. This new facility will be used to qualify the first self developed High Resolution Camera, which will be loaded on KOMPSAT-3. To perform an optical test for space camera, it is necessary to provide vibration free environment. Thus the vibration responses on the optical table due to external vibration should be minimized by using a special isolation system. In this paper, we propose the concept design of vibration isolation system for the development of the high resolution camera.

  • PDF

휴대폰용 카메라 모듈 구동기 및 셔터 (Camera Module Actuator and Electromechanical Shutter for Mobile Phone)

  • 정제현;이경택;이종진;이만형;홍삼열;고의석
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2005년도 추계학술대회논문집
    • /
    • pp.740-742
    • /
    • 2005
  • In the past, a mobile phone had only a function of communication. Recently, new functions such as an mp3 player and a camera are added in a mobile phone. For the application of a camera module to a mobile phone, the size of the camera module needs to become smaller than a general Digital Camera. Furthermore, it is also required that the performance of the camera module in a mobile phone be the same as that of a Digital Camera. In order to fulfill these requirements, the camera module should have functions such as Auto Focus, Zoom, the shutter and the aperture. Therefore, we introduce a simple and effective actuator and propose the shutter composed of solenoid.

  • PDF

저가의 머신 비전 카메라를 이용한 2차원 진동의 측정 및 교정 (Measurement of two-dimensional vibration and calibration using the low-cost machine vision camera)

  • 김서우;이정권
    • 한국음향학회지
    • /
    • 제37권2호
    • /
    • pp.99-109
    • /
    • 2018
  • 현존하는 진동 측정 센서는 정밀도 면에서는 대부분의 진동을 측정하기에 충분하나, 센서 한 개로 하나의 지점이나 방향에 한정하여 측정할 수밖에 없다는 단점을 갖고 있다. 반면 카메라의 경우, 정밀도나 측정 가능한 주파수 영역의 면에서는 다소 불리하지만, 한 번에 광범위한 영역의 진동을 측정할 수 있고 가격 면에서 유리하며 다자유도의 진동을 동시에 측정할 수 있다는 큰 장점을 갖고 있다. 본 연구에서는 저가의 머신 비전 카메라가 진동 측정 센서로서 어느 정도의 오차 범위 내에서 진동을 측정할 수 있는지 알아본 후, 실제 외팔보의 진동을 측정하였다. 카메라의 2차원 평면 이미지는 두 방향의 직선 운동과 한 방향의 회전 운동을 나타낼 수 있다. 먼저 단일 점의 진동을 카메라로 측정하고, LDV(Laser Doppler Vibrometer) 측정을 기준으로 한 카메라 측정의 오차를 실험적으로 교정하였다. 다음으로 다중점의 진동을 한 번에 측정하여 회전 진동과 외팔보 전체 형상의 진동을 측정하였다. 외팔보 전체 형상 진동은 주파수와 시간 영역 모두에 대하여 분석하였다.

VIBRATION DISPLACEMENT MEASUREMENT TECHNOLOGY FOR CYLINDRICAL STRUCTURES USING CAMERA IMAGES

  • SON, KI-SUNG;JEON, HYEONG-SEOP;PARK, JIN-HO;PARK, JONG WON
    • Nuclear Engineering and Technology
    • /
    • 제47권4호
    • /
    • pp.488-499
    • /
    • 2015
  • Acceleration sensors are usually used to measure the vibration of a structure. Although this is the most accurate method, it cannot be used remotely because these are contact-type sensors. This makes measurement difficult in areas that cannot be easily approached by surveyors, such as structures located in high or dangerous areas. Therefore, a method that can measure the structural vibration without installing sensors is required for the vibration measurement of structures located in these areas. Many conventional studies have been carried out on non-contact-type vibration measurement methods using cameras. However, they have been applied to structures with relatively large vibration displacements such as buildings or bridges, and since most of them use targets, people still have to approach the structure to install the targets. Therefore, a new method is required to supplement the weaknesses of the conventional methods. In this paper, a method is proposed to measure vibration displacements remotely using a camera without having to approach the structure. Furthermore, an estimation method for the measurement resolution and measurement error is proposed for the vibration displacement of a cylindrical structure measured using the proposed measurement method. The proposed methods are described, along with experimental results that verify their accuracy.