• Journal of Satellite, Information and Communications
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• v.5 no.1
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• pp.63-68
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• 2010

Satellite structure should be designed to support safely the payload and several actuators under launch and on-orbit environments. After the configuration design of satellite, the structural analysis is performed using quasi-static load provided by launch vehicle manufacturer for detail design of satellite. In order to verify the safety of satellite structure designed using quasi-static loads, launch vehicle manufacturer performs coupled load analysis with satellite and launch vehicle models. For developing satellite, satellite model was reduced into the Craig-Bampton model for coupled load analysis, and delivered to the launch vehicle manufacturer. Launch vehicle manufacturer have done the coupled load analysis, and offered the acceleration and displacement results to the satellite manufacturer. From the analysis results, we have confirmed that satellite is designed safely and there is no possibility of interference and conflict in the inner/outer side of satellite.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.4
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• pp.106-113
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• 2002

In spacecraft system, structure subsystem has the mission of supporting all the components safely under various space environmental conditions. The safety of spacecraft structure is finally verified from the coupled load analysis, which is a branch of load analysis which combines the launch vehicle and satellite. This study introduces the optimization algorithm to reduce the weight of spacecraft structure under launch environmental conditions directly. The acceleration responses are obtained by the introduction of coupled load analysis, which lead to check the failure of spacecraft structural members. The results show a 12% saving of structural weight and this saving is mainly driven by the thickness of honeycomb core, which strongly affects the natural frequencies of platforms and panels.

• Aerospace Engineering and Technology
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• v.5 no.2
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• pp.102-107
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• 2006

In this study, the dynamic environment of satellite consists of excessive vibration at low frequency and irregular acceleration transferred by launch vehicle structure. Excessive vibration at low frequency is generally approximated by a sinusoidal wave from 100Hz to 200Hz and primarily used to preliminary design The random vibration is created by structural vibration due to the combustion of launch vehicle, separation stage and external aerodynamic noise. these are transferred to the adapter structure between satellite and launch vehicle through the structure of launch vehicle. random vibration is being specified for acceptance tests, screening tests, and qualification tests, because it has been shown that random vibration more closely represents the true environments in which the electronic equipment must operate.

• Journal of Satellite, Information and Communications
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• v.5 no.2
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• pp.8-13
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• 2010

Satellite structure should be designed to accommodate and support safely the payload and equipments necessary for its own missions and to secure satellite and payloads from severe launch environments. The launch environments imposed on satellites are quasi-static accelerations, aerodynamic loads, acoustic loads and shock loads. Especially when optical payload is accommodated, satellite structure usually adopts the optical bench consisting of composite material not only to support and secure but also to guarantee good pointing stability against extreme thermal environments. This paper deals with optical bench and support structure which shall be designed to minimize the loads transferred to optical payloads from satellite.

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.145.2-145.2
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• 2005

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.6
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• pp.34-48
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• 2004

In this paper an optimization algorithm is suggested to reduce the huge computation time in the optimum design of large structures, especially in spacecraft structures. It combines the coupled load analysis model using a constrained mode of component mode synthesis and the modal transient analysis. The computer simulation code is developed and evaluated in optimizing spacecraft platforms. The developed algorithm can alleviate the computational load with adequate accuracy. From the optimization of a spacecraft structural member, the characteristics of each structural member can be understood.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.192.1-192.1
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• 2012

영상레이더 (SAR: Synthetic Aperture Radar) 혹은 통신 안테나/탑재체를 장착한 위성은 원하는 주파수 대역의 운용을 위해 대형 안테나 구조물 장착이 필수적이다. 이러한 대형 구조물은 일체형으로 제작되어 위성체에 접속되었을 때, 요구 무게 및 점유하는 부피가 매우 큰 특징을 지닌다. 따라서, 대형 안테나 구조물의 중량으로 인해 발사비 증가가 불가피하며, 페어링 내부의 허용된 공간에 안테나 크기는 큰 제약적 요인이 된다. 그리고, 전개식이어도, 전개후 질량 관성이 큰 구조물이 된다. 위성체의 발사 비용과 직결되는 안테나의 경량화를 위한 많은 기술이 연구되고 있다. 특히, 접이식 팽창형 안테나는 반사체의 유연한 메쉬 구조 및 경량 지지구조물로 안테나의 무게를 줄이고 수납 효율을 향상시킨다. 또한, 전개 후 안테나의 목적한 기능을 충분히 보장함과 동시에 질량 관성이 작은 구조물에 의한 위성의 기동성을 극대화할 수 있다. 국내에서도 전천후 지상관측감시 및 통신 안테나의 필요성 증대에 따라 초경량 전개형 안테나 개발의 필요성이 크게 대두되고 있으나, 현재까지는 관련 기술개발 사례가 전무한 실정으로 국내 독자적 기술 확보가 시급한 실정이다.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.179.1-179.1
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• 2012

정지궤도 복합위성 2호는 현재 기상 및 해양관련 관측임무를 수행중인 천리안위성의 임무승계를 위해 현재 개발이 진행 중이다. 천리안위성에 비해 수명이 확대되고, 임무 탑재체의 중량도 증가하여 추진제량의 대폭 증가가 필요한 것으로 분석되고 있다. 이로 인해 추진제 탱크의 확장이 불가피하여 현재 가용한 탱크를 기반으로 구조체 설계에 대한 비교 연구가 수행되었다. 정지궤도위성의 추진제 탱크 수용은 크게 측면 고정식 구형 탱크의 수직 배치방식과 극 고정식 실런더형 탱크의 수평 배치방식으로 구분된다. 추진제량 확대에 따라 두가지 방식 모두 구조체 내부에 충분한 강성확보와 하중전달을 목적으로 튜브형 구조물이 적용되며, 이를 토대로 구조체 설계가 이루어 진다. 본 논문에서는 이러한 추진계 탱크 수용 방식을 기반으로 정지궤도 복합위성에 적용될 구조체 설계 개념을 제시하고, 비교 연구를 통해 각 방식이 갖는 구조체 설계의 장단점을 기술하고자 한다.

• Composites Research
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• v.14 no.4
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• pp.8-14
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• 2001

The satellite system experiences severe mechanical loads during the launch period. Therefore, the positive margin of safety of the satellite system must be demonstrated for every possible mechanical loading conditions during the launch period. This paper presents modal and stress analysis results due to quasi-static loads for the satellite antenna system. The failure tendency fur the sandwich construction of the satellite antenna system has been studied with various lamination angles of unidirectional prepreg.

• Journal of Satellite, Information and Communications
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• v.7 no.3
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• pp.110-115
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• 2012

Satellite structure should be designed to accommodate and support safely the payload and equipments necessary for its own missions and to secure satellite and payloads from severe launch environments. The launch environments imposed on satellites are quasi-static accelerations, aerodynamic loads, acoustic loads and shock loads. Currently KARI(Korea Aerospace Research Institute) is developing Geo-KOMPSAT-2(Geostationary Earth Orbit KOrea Multi-Purpose Satellite) with technologies which were acquired during COMS(Communication, Ocean and Meteorological Satellite) development. As compared to COMS Geo-KOMPSAT-2 requires more propellant due to mass increase of Advanced Meteorological Payload with high resolution and increase of miss life, it is difficult to apply the design concept of COMS to Geo-KOMPSAT-2. This paper deals with conceptual design of Structural Subsystem for Geo-KOMPSAT-2.