• Title/Summary/Keyword: spacecraft control

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Status and Prospect of Spacecraft Propulsion System (우주비행체 추진기관 기술 현황 및 전망)

  • Kim, Su-Kyum;Chae, Jong-Won;Won, Su-Hee;Jun, Hyong-Yoll
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.44 no.8
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    • pp.695-701
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    • 2016
  • Spacecraft propulsion system is a kind of rocket engine that has been developed from the end of 1950s for attitude control and orbit maintenance of satellite. Since the spacecraft propulsion system has to be used for a relatively long time, therefore, stability of propellant and life of thruster could be very important factor for propulsion system design. Recently, green propellant propulsion and all electrical propulsion system have became very important issue, and we also need a development according to well organized plan. In this paper, we will introduce the development status, key technologies and development prospect of spacecraft propulsion system.

Relay of Remote Control Signal for Spacecraft in Deep Space via FHLH (FHLH를 매개로 한 심우주 우주선 원격 제어 신호 중계)

  • Koo, Cheol Hea;Kim, Hyungshin
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.48 no.4
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    • pp.295-301
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    • 2020
  • When a spacecraft in deep space falls into an abnormal state, an emergency communication channel between ground and the spacecraft is essential in order to perform analysis to the cause of the anomaly, and to remedy the spacecraft from the distressed state. Because the recovery actions generally comprises of long and complicated sequences of commands, the transmission of the recovery commands may require a reliable and a delay tolerant networking technology based on bundle routing. While the delay tolerant networking protocol becomes a prominent method interfacing ground and space into a internet-like Solar system network because it can address the issues of the severe communication problems in deep space, the communication system on the spacecraft which based on space packet protocol cannot use the delay tolerant networking technology directly. So a community of the consultative committee for space data systems starts a discussion of the first-hop last-hop mechanism to establish a feasible concept and standardization. This paper presents an enhanced concept of the first-hop last-hop by applying it a virtual cislunar communication environment, and we believe this contributes to make a way applicable to an interoperable relay concept of the first hop last hop between the delay tolerant networking and space packet protocol standard.

Multiple Battery Module for the Low-Earth-Orbit Spacecraft Power system

  • Cho Yoon-Jay;Cho B. H.
    • Proceedings of the KIPE Conference
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    • 2001.10a
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    • pp.84-88
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    • 2001
  • In an effort to develop more reliable and cost-effective satellite power system, a multiple-battery subsystem operating in parallel become a viable solution. The idea can further be extended to the parallel-able standardized battery module concept that offers many attractive features in configuring a spacecraft power system. In this paper, Multiple Battery Modules employing the charge control scheme are proposed. In addition to the conventional voltage mode controller, the charge control scheme internally regulates and controls the battery current, resulting in the identical current distribution and balanced battery charge.

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Improvement of Time Synchronization over Space Wire Link (스페이스와이어 링크의 시각 동기 성능 개선)

  • Ryu, Sang-Moon
    • Journal of Institute of Control, Robotics and Systems
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    • v.15 no.11
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    • pp.1144-1149
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    • 2009
  • This paper deals with the time synchronization problem over SpaceWire links. SpaceWire is a standard for high-speed links and networks between spacecraft components, which was invented for better, cheaper, faster on-board data handling in spacecraft. The standard defines Time-Code for time distribution over SpaceWire network. When a Time-Code is transmitted, transmission delay and jitter is unavoidable. In this paper, a mechanism to remove Time-Code transmission delay and jitter over SpaceWire links is proposed and implemented with FPGA for validation. The proposed mechanism achieves high resolution clock synchronization over SpaceWire links, complies with the standard and can be easily adopted over SpaceWire network.

Inertia Estimation of Spacecraft Based on Modified Law of Conservation of Angular Momentum

  • Kim, Dong-Hoon;Choi, Dae-Gyun;Oh, Hwa-Suk
    • Journal of Astronomy and Space Sciences
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    • v.27 no.4
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    • pp.353-357
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    • 2010
  • In general, the information of inertia properties is required to control a spacecraft. The inertia properties are changed by some activities such as consumption of propellant, deployment of solar panel, sloshing, etc. Extensive estimation methods have been investigated to obtain the precise inertia properties. The gyro-based attitude data including noise and bias needs to be compensated for improvement of attitude control accuracy. A modified estimation method based on the law of conservation of angular momentum is suggested to avoid inconvenience like filtering process for noise-effect compensation. The conventional method is modified and beforehand estimated moment of inertia is applied to improve estimation efficiency of product of inertia. The performance of the suggested method has been verified for the case of STSAT-3, Korea Science Technology Satellite.

Thermally Induced Vibration Control of Flexible Spacecraft Appendages Using by Piezoelectric Material (압전재료를 이용한 위성체 구조물의 열 진동 제어)

  • 윤일성;송오섭;김규선
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.05a
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    • pp.303-310
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    • 2002
  • The bending vibration and thermal flutter instability of spacecraft booms modeled as circular thin-walled beams of closed cross-section and subjected to thermal radiation loading is investigated in this paper. Thermally induced vibration response characteristics of a composite thin walled beam exhibiting the circumferantially uniform system(CUS) configuration are exploited in connection with the structural flapwise bending-lagwise bending coupling resulting from directional properties of fiber reinforced composite materials and from ply stacking sequence. The numerical simulations display deflection time-history as a function of the ply-angle of fibers of the composite materials, damping factor, incident angle of solar heat flux, as well as the boundary of the thermal flutter instability domain. The adaptive control are provided by a system of piezoelectric devices whose sensing and actuating functions are combined and that an bonded or embedded into the host structure.

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The nonlinear fuzzy intelligent theory for high-bypass-ratio two-spool unmixed-flow jet engines

  • C.C. Hung;T. Nguyen
    • Advances in aircraft and spacecraft science
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    • v.10 no.4
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    • pp.369-391
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    • 2023
  • In our research we have offered a solid solution for aeronautical analysis. which can guarantee the asymptotic stability of coupled nonlinear facilities. According to the theoretical solutions and methods presented, the engine of this aircraft is a small high-bypass turbofan engine. using the non-linear aero-motor control approach and this paper focuses on the power management function of the aero-motor control system. These include static controls and transient controls. A mathematical model of the high-bypass-ratio two-spool unmixed-flow aeroengine was developed through a set of nonlinear dynamic equations verified by experimental data. A single actuator using the displacement method is designed to maintain a certain level of thrust under steady-state conditions. and maintains repeatable performance during transient operation from the requested thrust phase to the next. A single controller can compensate for the effects of noise and harmonic noise at many performance points. And the dynamic performance of a single controller is satisfactory during the transient. for fairness Numerical and computer experiments are described in the perfection of the methods we offer in research.