• 제목/요약/키워드: Attitude Control System

검색결과 707건 처리시간 0.044초

Star Visibility Analysis for a Low Earth Orbit Satellite

  • Yim, Jo-Ryeong;Lee, Seon-Ho;Yong, Ki-Lyuk
    • 한국우주과학회:학술대회논문집(한국우주과학회보)
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    • 한국우주과학회 2008년도 한국우주과학회보 제17권2호
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    • pp.28.2-28.2
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    • 2008
  • Recently, star sensors have been successfully used as main attitude sensors for attitude control in many satellites. This research presents the star visibility analysis for star trackers and the goal of this analysis is to make sure that the star tracker implementation is suitable to the mission profile and scenario and satisfies the requirement of attitude orbit control system. As a main optical attitude sensor imaging stars, accomodations of a star tracker should be optimized in order to improve the probability of the usage by avoiding the blinding (the unavailability) by the Sun and the Earth. For the analysis, a statistical approach and a time simulation approach are used. The statistical approach is based on the generation of numerous cases, to derive relevant statistics about Earth and Sun proximity probabilites for different lines of sight. The time simulation approach is performed for one orbit to check the statistical result and to refine the statistical result and accomodations of star trackers. In order to perform simulations first of all, an orbit and specific mission profiles of a satellite are set, next the earth proximity probability and the sun proximity probability are calculated by considering the attitude maneuvers and the geometry of the orbit, and then finally the unavailability positions are estimated. As a result, the optimized accomodations of two star trackers are suggested for the low earth orbit satellite.

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3축 자세 제어용 센서 시스템의 구현 (Implementation of the 3 axes Attitude Control Sensor System)

  • 정종원;최우진;지석준;이기영;이준탁
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 D
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    • pp.2329-2331
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    • 2001
  • In this paper, were developed the 3 axes attitude control sensor system to control and monitoring the moving object. The proposed sensor system has been studied in Japan, America for a year ago. But it is high expensive and has a difficulty in application. To overcome these problems, proposed the 3 axes attitude control sensor system is low cost and easily applied. Proposed sensor system is equipped with the 3 gyro sensors, 2 tilt sensors and 3 MR sensors using 80C51 microprocessor for signal processing. It's output value transmit at long distance using RS232 serial communication protocol. We expect this system shall have a good performances in many applications of control and monitoring the moving object.

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Development of a Hardware-In-Loop (HIL) Simulator for Spacecraft Attitude Control Using Momentum Wheels

  • Kim, Do-Hee;Park, Sang-Young;Kim, Jong-Woo;Choi, Kyu-Hong
    • Journal of Astronomy and Space Sciences
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    • 제25권4호
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    • pp.347-360
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    • 2008
  • In this paper, a Hardware-In-the-Loop simulator to simulate attitude control of space craft using momentum wheels is developed. The simulator consists of a spherical air bearing system allowing rotation and tilt in all three axes, three momentum wheels for actuation, and an AHRS (Attitude Heading Reference System). The simulator processes various types of data in PC104 and wirelessly communicates with a host PC using TCP/IP protocol. A simple low-cost momentum wheel assembly set and its drive electronics are also developed. Several experiments are performed to test the performance of the momentum wheels. For the control performance test of the simulator, a PID controller is implemented. The results of experimental demonstrations confirm the feasibility and validity of the Hardware-In-the-Loop simulator developed in the current study.

GAFC 비선형 제어기법을 적용한 쿼드로터의 자세 및 고도제어 (Nonlinear Attitude Control for Uncertain Quad-rotors Using a Global Approximation-Free Control Scheme)

  • 김영욱;박성용;이현재
    • 제어로봇시스템학회논문지
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    • 제22권10호
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    • pp.779-787
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    • 2016
  • A nonlinear control law for the quad-rotor of a low-complexity, global approximation-free from system uncertainties and external disturbances are described in this paper. The control law guarantees convergence to a small bounded error using a prescribed performance function. The stability of the proposed nonlinear control system is also proven by the Lyapunov stability theorem. The advantage of this technique is that it has a simpler form than any other nonlinear compensators and is applicable to any nonlinear systems without precise knowledge of the systems. In this paper, the proposed approach is applied to attitude/altitude control of a quad-rotor. Numerical simulations are performed to investigate the proposed nonlinear attitude control law by applying it to an uncertain quadcopter system with external disturbances.

Lyapunov 변환을 이용한 SDINS 등가 오차모델 (SDINS Equivalent Error Models Using the Lyapunov Transformation)

  • 유명종;이장규;박찬국
    • 제어로봇시스템학회논문지
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    • 제8권2호
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    • pp.167-177
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    • 2002
  • In Strapdown Inertial Navigation System(SDINS), error models based on previously proposed conversion equations between the attitude errors, are only valid in case the attitude errors are small. The SDINS error models have been independently studied according to the definition of the reference frame and of the attitude error. The conversion equations between the attitude errors applicable to SDINS with large attitude errors are newly derived. Lyapunov transformation matrices are also derived from the obtained results. Furthermore the general method, which is independent of the attitude error and the reference frame to derive SDINS error model, is proposed using the Lyapunov transformation.

추력벡터제어를 이용한 고고도 종말 유도조종 루프 설계 (High-Altitude Terminal Guidance and Control Loop Design Using Thrust Vector Control)

  • 전하민;박종호;유창경
    • 한국항공우주학회지
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    • 제50권6호
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    • pp.393-400
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    • 2022
  • 고고도 교전 시 사용되는 궤도수정 및 자세제어 시스템(Divert and Attitude Control System, DACS)은 고가이며 복잡하다. 본 논문에서는 비교적 단순하고 저가인 추력벡터제어(Thrust Vector Control, TVC)를 탑재한 유도탄의 고고도 종말 유도조종 루프를 제안한다. 본 유도조종 루프는 쿼터니언 피드백 제어기법을 이용하여 진 비례항법유도로 산출된 가속도 명령으로부터 변환된 추력 자세각 명령을 추종하며 유도를 수행한다. 고고도에서 탄도탄에 대한 교전 시뮬레이션을 통하여 제안한 유도조종 루프의 성능을 분석한다.

HAUSAT-2 자세제어 성능 해석 (ANALYSIS OF THE HAUSAT-2 ATTITUDE CONTROL)

  • 이병훈;김수정;장영근
    • 한국우주과학회:학술대회논문집(한국우주과학회보)
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    • 한국우주과학회 2005년도 한국우주과학회보 제14권1호
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    • pp.133-137
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    • 2005
  • 우주시스템 연구실에서 개발 중인 HAUSAT-2의 피치모멘텀 바이어스 시스템을 설계하고 성능을 검증하였다. HAUSAT-2의 자세제어시스템은 초기자세획득모드와 정상모드로 분리되어 궤도에서 운용된다. 본 논문은 피치모멘텀 바이어스 시스템을 사용하여 위성이 운용될 경우 각 모드에 따라 자세제어가 가능한 범위를 해석하였고 ,모멘팀 휠 구동에 의하여 발생되는 모멘팀 덤핑 현상에 대하여 연구하였다.

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궤도천이 및 자세제어 시스템의 연구개발 동향과 전망 (Recent Progress in R&D and Prospect of Divert and Attitude Control System(DACS))

  • 김성수;허환일
    • 한국추진공학회지
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    • 제16권6호
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    • pp.62-72
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    • 2012
  • 우주 비행체와 유도 미사일에 적용되는 궤도천이 및 자세제어 시스템(이하 DACS)은 비행체의 궤도를 천이시키거나 미세한 자세 제어를 수행하게 된다. DACS를 개발하기 위해서는 추력변화 최대화를 위한 핀틀/노즐의 형상 조합, 핀틀 구동력 최소화를 위한 공력하중 저감, 다축 제어 알고리즘에 대한 연구가 중요하다. 본 논문에서는 이러한 DACS 시스템에 대한 소개와 분류, 국내외 연구 개발 동향에 대해 살펴보고 향후 연구 개발 전망을 제시하였다.

인공위성의 Roll축 자세제어시스템 설계 및 검증 (Design and Verification of Satellite Attitude Control system for Roll Maneuver)

  • 김희섭;김기석;안재명;김유단;최완식
    • 제어로봇시스템학회논문지
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    • 제5권3호
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    • pp.370-378
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    • 1999
  • KOMPSAT is a three-axis stabilized light weight satellite, and one of the main mission objectives of the KOMPSAT is to conduct scientific and technological analysis in the areas of high resolution imaging and ocean color imaging. This kind of mission requires the satellite to roll up to 45 degrees. Bang-bang control for this rolling maneuver may activate the flexible modes, and therefore cause satellite pointing performance degradation. To deal with this problem, the roll attitude control system, especially for the science mode and maneuver mode of the KOMPSAT, is first verified by numerical simulation. And the open-loop control law for roll maneuver is proposed by use of series expansion and optimization. The proposed control law is applied to KOMPSAT to see its effectiveness.

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영구자석 안정화 자세제어 방식이 적용된 큐브위성의 열적 특성분석 (Numerical Investigation of On-orbit Thermal Characteristics for Cube Satellite with Permanent Magnet Attitude Stabilization Method)

  • 강수진;정현모;오현웅
    • 항공우주시스템공학회지
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    • 제7권3호
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    • pp.26-32
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    • 2013
  • Passive attitude stabilization method has been widely usde for attitude determination and control of cube satellite due to its advantage of system simplicity. The permanent magnet installed on the cube satellite passively controls the attitude of the satellite such that the satellite is aligned with the earth magnetic field. In this paper, on-orbit thermal behavior of the cube satellite with the permanent magnet attitude stabilization method has been investigated through on-orbit thermal analysis. THe orbit profile obtained from the aforementioned attitude control method has been reflected in the analysis. The analysis results indicate that the thermal design proposed in this study is effective for satisfying the temperature requirements of the commericial mission equipments.