• 제목/요약/키워드: Micro Positioning

검색결과 153건 처리시간 0.027초

광학관측위성의 영상품질열화 최소화를 위한 반작용휠 최적위치 선정 (Optimal positioning of reaction wheel assemblies of optical observation satellite for minimizing image quality degradation)

  • 임정흠;임재혁;김경원;윤형주;김성훈
    • 항공우주시스템공학회지
    • /
    • 제12권6호
    • /
    • pp.9-16
    • /
    • 2018
  • 본 논문에서는 반작용휠 미소진동시험 결과 및 유한요소모델 기반 광기계해석 통합모델을 이용해 영상품질저하 예측을 실시하고 해석결과를 바탕으로 기준 회전수에서 영상품질관점에서 최적의 반작용휠 배치조합을 찾는 것을 목적으로 한다. 위성은 적절한 기동성능을 위하여 여러 개의 반작용휠을 장착하는데 반작용휠에서 발생하는 미소진동은 위성영상품질 열화에 원인이 된다. 같은 반작용휠이라도 제조과정상 발생하는 제품의 진동특성차이가 있으며 이를 반영한 반작용휠의 배치설계는 최종 위성영상 성능품질 열화를 최소화시킬 수 있다. 이를 위해 본 연구에서는 모든 반작용휠의 배치상태를 선정하고 이에 따른 영상품질 열화해석을 실시하여 최소의 열화가 일어나는 반작용휠 배치조합을 찾아내었다.

다중속도 INS/GPS 결합항법시스템의 실시간 구현을 고려한 수정된 UKF (Modified UKF Considering Real-Time Implementation of the Multi-Rate INS/GPS Integrated Navigation System)

  • 조성윤;문흐줄;김경호
    • 제어로봇시스템학회논문지
    • /
    • 제19권2호
    • /
    • pp.87-94
    • /
    • 2013
  • UKF (Unscented Kalman Filter) has been used in the nonlinear systems without initial accurate state estimates instead of EKF (Extended Kalman Filter) of the last decade because the UKF has robustness to the large initial estimation error. In the multirate integrated system such as INS (Inertial Navigation System)/GPS (Global Positioning System) integrated navigation system, however, it is difficult to implement the UKF based navigation algorithm in the mid-grade micro-processor due to the large computational burden. To overcome this problem, this paper proposes a MUKF (Modified UKF) that has a reduced computation burden using the basic idea that the change of the provability distribution for the state variables between measurement updates is small in the multi-rate INS/GPS integrated navigation filter. The performance of the proposed MUKF is verified by numerical simulations.

초정밀 데스크탑 마이크로 NC 선반 개발 및 성능평가 (Development and Evaluation of Ultra-precision Desktop NC Turning Machine)

  • 노승국;박종권;박현덕;김양근
    • 한국생산제조학회지
    • /
    • 제22권4호
    • /
    • pp.747-754
    • /
    • 2013
  • This study introduces a recently designed desktop-sized NC turning system and its components. This machine is designed for the ultra-precise turning of parts with a diameter of 0.5-20 mm with minimum space usage for the machine. This study aims to achieve submicron-level accuracy of movements and good rigidity of the machine for precision machining using the desktop-sized machine. The components such as the main machine structure, air bearing servo spindle, and XZ stage with needle roller guides are designed, and the designed machine is built with a PC-based CNC controller. Its static and dynamic stiffness performances and positioning resolutions are tested. Through machining tests with single-crystal diamond tools, a form error less than $0.8{\mu}m$ and surface roughness (Ra) of $0.03{\mu}m$ for workpieces are obtained.

정밀저울을 이용한 원자힘 현미경 캔티레버의 특성평가 (Atomic Force Microscope Probe Calibration by use of a Commercial Precision Balance)

  • 김민석;최인묵;박연규;최재혁;김종호
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2005년도 춘계학술대회 논문집
    • /
    • pp.637-640
    • /
    • 2005
  • In this paper, we investigate the characteristics of a piezoresistive AFM cantilever in the range of $0\~30{\mu}N$ by using nano force calibrator (NFC), which consists of a high precision balance with resolution of 1 nN and 1-D fine positioning stage. Brief modeling of the cantilever is presented and then, the calibration results are shown. Tests revealed a linear relationship between the probing force and sensor output (resistance change), and the force vs. deflection. From this relationship, the force constant of the cantilever was calculated to 3.45 N/m with a standard deviation of 0.01 N/m. It shows that there is a big difference between measured and nominal spring constant of 1 N/m provided by the manufacturer s specifications.

  • PDF

바이오셀 조작을 위한 원격조작 로봇 시스템 (Telerobot System for Biocell Manipulation)

  • 가포노브 이고르;조현찬
    • 한국실천공학교육학회논문지
    • /
    • 제3권1호
    • /
    • pp.193-199
    • /
    • 2011
  • 본 논문에서는 원격조작 미세조정을 위한 매니퓰레이터를 제안한다. $2{\mu}m$정도의 정밀도를 갖는 매니퓰레이터를 설계하고 제어하기 위해 매니퓰레이터의 정밀도를 사전 계산하였고 그에 따른 각종 부품들로 실 시스템을 제작 하였다. 본 논문에서 제작된 원격조작 로봇 시스템은 여러 미세동작 제어 실험을 통해 그 정밀도가 검증하였고 원격 조작 로봇 시스템의 한 부분으로서 미세조정 매니퓰레이터의 적절성이 증명되었다. 제안된 매니퓰레이터는 아나로그적인 여러 요소로 제작 되었으며 논문에서 시스템의 장단점을 분석 하였다.

  • PDF

Design and Performance Evaluation of a 3-DOF Mobile Microrobot for Micromanipulation

  • Park, Jungyul;Kim, Deok-Ho;Kim, Byungkyu;Kim, Taesung;Lee, Kyo-Il
    • Journal of Mechanical Science and Technology
    • /
    • 제17권9호
    • /
    • pp.1268-1275
    • /
    • 2003
  • In this paper, a compact 3-DOF mobile microrobot with sub-micron resolution is presented. It has many outstanding features : it is as small as a coin ; its precision is of sub-micrometer resolution on the plane ; it has an unlimited travel range ; and it has simple and compact mechanisms and structures which can be realized at low cost. With the impact actuating mechanism, this system enable both fast coarse motion and highly precise fine motion with a pulse wave input voltage controlled. The 1 -DOF impact actuating mechanism is modeled by taking into consideration the friction between the piezoelectric actuator and base. This modeling technique is extended to simulate the motion of the 3-DOF mobile robot. In addition, experiments are conducted to verify that the simulations accurately represent the real system. The modeling and simulation results will be used to design the model-based controller for the target system. The developed system can be used as a robotic positioning device in the micromanipulation system that determines the position of micro-sized components or particles in a small space, or assemble them in the meso-scale structure.

캠-슬라이더 메커니즘 테이프 피더의 성능평가에 관한 연구 (A Study on the Performance Analysis for a Tape Feeder with Cam-slider Mechanism)

  • 전병철;조명우;문찬영;이수진;최진화
    • 한국정밀공학회지
    • /
    • 제23권5호
    • /
    • pp.177-183
    • /
    • 2006
  • A tape feeder is an important feeding device to supply micro-chips such as 1005 and 0603 components to PCB in SMT process. Traditionally, tape feeding methods using sprocket wheel mechanism has been used for the pickup system of chip-mounters. However, there is growing needs for new feeding mechanism with high accuracy and confidence as electric components are getting much smaller. Thus, recently, a tape feeder using cam-slider mechanism is developed to meet such requirements. The major advantages of developed system are; significantly reduced indexing and backlash errors, slim and compact design, and improved repetitive capacity compared to existing system. In this paper, the performance evaluation criteria for the developed tape feeder are suggested. Stability against induced vibration, positioning accuracy, cycle time, durability and supply error rate are estimated using developed self testers. As a result, the excellence of developed tape feeding mechanism is validated using the effective rating methods.

Actuator용 전왜재료의 특성개선을 위한 압전재료의 첨가효과 (The Effect of Piezoelectric Ceramic for Properties Improvement at Electrostriction Ceramic)

  • 이수호;조현철;김한근;손무현;사공건
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 1997년도 추계학술대회 논문집
    • /
    • pp.206-210
    • /
    • 1997
  • In the fields of the optics, precise machine, semiconductors, the micro-positioning actuators are required for the control of position in the submicron range. PNN-P2N-PZT ceramics were fabricated with various mole ratio of the PZT[Pb(Zr$_{1}$2//Ti$_{1}$2)O$_3$]. PNN (Pb(Ni$_{1}$3/Nb$_{2}$3/)O$_3$]and PZN[Pb(Zn$_{1}$3//Nb/sbu 2/3/)O$_3$] powders prepared by double calcination and PZT powders prepared by molten- salt synthesis method. The relative permittivity of specimen with PZT 0.3 mole ratio was shown 5,320 and appeared the relaxor ferroelectric feature. The maximum Piezoelectric coefficient d$_{31}$ to be used for evaluation the displacement of piezoceramics in PNN-PZN-PZT ceramics was 324$\times$10$^{-12}$ (C/V) at the vicinity of morphotropic phase boundary and was larger than that of solid PZT ceramics(120$\times$10$^{-12}$ C/V).

  • PDF

소형공작기계를 이용한 광커넥터용 V 홈 가공에 관한 연구 (A Study on Machining of A V-groove on the Optical Fiber Connector Using a Miniaturized Machine Tool)

  • 이재하;박성령;양승한;이영문
    • 한국정밀공학회지
    • /
    • 제21권5호
    • /
    • pp.38-45
    • /
    • 2004
  • As optical communication is being substituted for telecommunication, the demand of a large variety of fiber optic components is increasing. V-groove substrates, one of the module components, are used to connect optical fibers to optical planar circuits and to arrange fibers. Their applications are multi-channel optical connectors and optical waveguide fiber coupling, etc. Because these substrates are a critical part of the splitter in a multiplexer and a multi fiber connector, precise and reliable fabrication process is required. For precisely aligning core pitch between fibers, machined core pitch tolerance should be within sub-microns. Therefore, these are generally produced by state-of-the-art micro-fabrication like MEMS. However, most of the process equipment is very expensive. It is also difficult to change the process line for custom designs to meet specific requirements using various materials. For various design specifications such as different values of the V angle and low-priced process, the fabrication method should be flexible and low cost. To achieve this goal, we have suggested a miniaturized machine tool with high accuracy positioning system. Through this study, it is shown that this cutting process can be applied to produce V-groove subtracts. We also show the possibility of using a miniaturized machining system for producing small parts.

보행행태조사방법론의 변화와 모바일 빅데이터의 가능성 진단 연구 - 보행환경 분석연구 최근 사례를 중심으로 - (Changes in Measuring Methods of Walking Behavior and the Potentials of Mobile Big Data in Recent Walkability Researches)

  • 김현주;박소현;이선재
    • 대한건축학회논문집:계획계
    • /
    • 제35권1호
    • /
    • pp.19-28
    • /
    • 2019
  • The purpose of this study is to evaluate the walking behavior analysis methodology used in the previous studies, paying attention to the demand for empirical data collecting for urban and neighborhood planning. The preceding researches are divided into (1)Recording, (2) Surveys, (3)Statistical data, (4)Global positioning system (GPS) devices, and (5)Mobile Big Data analysis. Next, we analyze the precedent research and identify the changes of the walkability research. (1)being required empirical data on the actual walking and moving patterns of people, (2)beginning to be measured micro-walking behaviors such as actual route, walking facilities, detour, walking area. In addition, according to the trend of research, it is analyzed that the use of GPS device and the mobile big data are newly emerged. Finally, we analyze pedestrian data based on mobile big data in terms of 'application' and distinguishing it from existing survey methodology. We present the possibility of mobile big data. (1)Improvement of human, temporal and spatial constraints of data collection, (2)Improvement of inaccuracy of collected data, (3)Improvement of subjective intervention in data collection and preprocessing, (4)Expandability of walking environment research.