• Proceedings of the KSME Conference
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• 2001.11b
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• pp.77-82
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• 2001

Thermal design for KOMPSAT-2 propulsion system has been performed. Overall design requirements and the constitution for propulsion system is described. To meet the thermal design requirements, both a primary and a redundant heater circuit, each with two thermostats placed in series, will protect each hydrazine-wetted components, even if one heater circuit fails to operate. Heater power is turned off if any one of these thermostats is opened at its higher setpoint. Thus, even if one thermostat is failed closed, the second thermostat will turn off the heater. All such components shall be insulated with MLI. Propulsion heater sizing based on the constant worst cold case condition is conducted through thermal analysis. All heaters selected for propulsion components operate to prevent propellant freezing satisfying the thermal requirements for the propulsion subsystem over the worst case average voltage, i.e. 25 volts.

• Aerospace Engineering and Technology
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• v.2 no.2
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• pp.76-82
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• 2003

To guarantee the proper functions of a satellite in the extreme space environment, the several test models are developed generally. There are advantages that the design and the analysis of Flight Model(FM) can be validated through these test models, and the functional reliabilities can be increased by reflecting the modifications on the final design of FM. The integration and test of Structure & Thermal Model(STM) of KOMPSAT, being currently developed, have been completed. In this paper, the processes of design and analysis of the STM propulsion system, one of the KOMPSAT modules, are described.

• Journal of Astronomy and Space Sciences
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• v.15 no.2
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• pp.485-497
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• 1998

To estimate the availability of the MCE for KOMPSAT I, mathematical models of H/W and S/W availability, the availability estimating methods for parallel and redundant system were presented. Furthermore, to improve and estimate the MCE system availability, we analyzed the computational procedure of redundant methods, and we also included effective switch choosing methods in this paper. The analytical results of the MCE system availability were estimated as follows: - 0.995216 not considering system redundancy, - 0.9955165 considering system redundancy, and -0.9963991 for the time of system real time operation.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.4
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• pp.53-59
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• 2003

Strain Energy Hinge(SEH) has been used in Korea Multi-purpose Satellite(KOMPSAT) series to deploy the solar panel due to the good record of reliability. However, when it reached a desired deployment position, a large buckling force is applied to the main body. This may cause structural damage and also affect control of the satellite. Therefore, reliable dynamic analysis for the deployment system is required at a design stage. Moreover, various mission of a satellite has made the size of solar panels got bigger, so elastic effect has to be considered seriously to get more precise analysis results. In this paper, a dynamic analysis method to predict the deployment is verified by KOMPSAT-2 deployment test.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.1
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• pp.92-99
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• 2008

KOMSAT-5 will attach an laser retroreflector array for precise orbit determination. Laser retroreflector array was developed by DFZ in Germany and have pyramid type composed of four corner cube prisms. In this paper, the performance analyses as effective area of retroreflector and photons measured by link budget and position of ground station were performed.

• Aerospace Engineering and Technology
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• v.1 no.1
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• pp.97-105
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• 2002

The mission life of a satellite determines the amount of fuel required on-board, while the total mass requirement limits the fuel to be loaded. Hence, for the design of thruster control loop, not only the satellite pointing accuracy but the saving of fuel is to be considered. In this paper, a two-step fuzzy controller is proposed for the thruster control loop to save fuel consumption. This approach combines requirements for pointing control accuracy with minimum fuel consumption into a fuzzy controller design. To demonstrate this approach, we have designed a fuzzy controller for the Sun Pointing Mode of KOMPSAT-1. The performance of this fuzzy controller design is compared with that of PD controller used for KOMPSAT-1.

• Bulletin of the Korean Space Science Society
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• 2004.04a
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• pp.81-81
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• 2004

위성체와 발사체 사이에는 임무설계접속, 기계접속, 전기접속, 환경접속 등 다양한 접속이 존재한다. 본 논문은 2004년 1월 수행된 발사체 전기접속 시험을 통하여 검증한 다목적 실용위성 2호와 ROCKOT 발사체간 전기접속과 발사장에서의 위성체, 발사체, 지상지원 장비 및 임무통제센터를 포함한 주변 지원시설간 접속을 기술하였다. 본 시험의 목적은 KIA(KOMPSAT-2 Interface Assembly)를 포함한 발사체 TMS(Telemetry Measure ment System)와 다목적실용위성 2호 사이의 호환성을 검증하고 LV TMS와 위성체 LSTS (Launch Support ＆ Test Set)의 하드웨어 및 소프트웨어의 정확한 동작을 검증하는 것이다. (중략)

• Journal of the Korean Society of Propulsion Engineers
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• v.1 no.2
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• pp.67-73
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• 1997

This paper shows the development status of attitude control thruster for KOMPSAT(Korea Multi-Purpose Satellite). Hanwha Corp. has manufactured and delivered 1.0 lbf monopropellant thrusters under the technology transfer of TRW Co. in U.S.A regarding design, analysis and manufacturing of MRE-1 thruster These thrusters will be installed to KOMPSAT which is scheduled to be launched in July 1999. Monopropellant thrusters can provide reliable and cost-effective means of propulsive control for middle class satellite and maneuvering control systems. Some information concerning with system specification, performance analysis/simulations and manufacturing process has been introduced in this paper.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.11a
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• pp.325-328
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• 2004

본 논문은 다목적실용위성 2호기의 개발에 사용한 태양전지 어레이의 설계결과를 요약하였다. 최적의 태양전지 어레이의 개발을 위하여 고효율의 갈륨-아세나이드 태양전지를 사용하였다. 태양전지를 장착하기 위한 패널은 알루미늄 허니컴이 적용되는 샌드위치 구조에 섬유강화 복합재료를 면재로 사용하였다. 다목적실용위성 2호기의 임무말기 태양전지 어레이는 최소 1,073 watts 이상의 전력을 위성부하와 탑재체에 충분히 공급할 수 있도록 개발하고 있다.

• Aerospace Engineering and Technology
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• v.3 no.1
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• pp.97-102
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• 2004

Propulsion System provides the required velocity change impulse for orbit transfer from parking orbit to mission orbit and three-axis vehicle attitude control impulse. KOMPSAT-2 propulsion system(PS) is an all-welded, monopropellant hydrazine system. The PS consists of the subassemblies and components such as Thrusters, Propellant Tank, Pressure Transducer, Propellant Filter, Latching Isolation Valves, Fill/Drain Valves, interconnecting propellant line assembly, and thermal hardwares for operation-environment control of the PS. This paper summarizes a development process of the liquid propulsion system from the design engineering up to the test and evaluation.