우주발사체 개발사업의 비용 추정 현황 및 사례

유일상(Il-Sang Yoo),서윤경(Yun-Kyoung Seo),이준호(Joon Ho Lee),오범석(Bum-Seok Oh) 한국산업경영시스템학회 2007 한국산업경영시스템학회지 Vol.30 No.3

  A space launch vehicle system represents a typical example of large-scale multi-disciplinary systems, consisting of subsystems such as mechanical structure, electronics, control, telecommunication, propulsion, material engineering etc. A lot of cost is required to develop the launch vehicle system. A precise planning of R&D cost is very essential to make a success of the launch vehicle development program. Especially in the early development phase of a new space launch vehicle system, cost estimation techniques and analogy from past similar development data are very useful methods to estimate a development cost of the launch vehicle system.<BR>  Now Korea Aerospace Research Institute is in charge of the KSLV-I (Korea Space Launch Vehicle-I) Program that is a part of Korea National Space program. KSLV-I Program is a national undertaking to develop launch capabilities to deliver science satellites of a 100kg-class into a low earth orbit. It is hereafter, going to plan to develop a new korean space launch vehicle. In this paper, first the development costs of well-known launch vehicles in the world are presented to provide a reference to make a development plan of a new launch vehicle. Second this paper introduces the present status of cost estimation applications at NASA. Finally this paper presents the results from application of a TRANSCOST, a parametric cost model, to derive a cost estimate of a new launch vehicle development, as an example.

재사용 우주 발사체 개발 동향

정석규,배진현,정기정,구자예,윤영빈 한국항공우주학회 2017 韓國航空宇宙學會誌 Vol.45 No.12

With the recent development of space technology, the satellite market, especially the small satellite market, is growing globally. As the satellite market continues to grow, the launch vehicle market is also growing, and demand for low-cost launches is increasing. There are a number of options for low-cost launches, including development of engine that uses low-cost propellants, product and transportation cost savings, but the most effective way to reduce launch costs is to reuse the used launch vehicles. USA’s Space Shuttle, a famous rocket as manned spacecraft, could be referred as the start of reusable launch vehicle. However, Space Shuttle had limited reusable parts and it was very expensive even though it is a reusable launch vehicle because of its low efficiency. In recent years, aiming at a real reusable launch vehicle, reusable launch vehicle for commercial purposes have been developed around USA’s SpaceX and Blue Origin, and re-landing tests were successfully accomplished. In addition, SpaceX successfully did the re-using of first-stage launch vehicle that had been succeeded in re-landing already. In accordance with this trend, countries such as Europe and India are also concentrating on the study of reusable launch vehicles. Including Blue Origin, companies like Virgin Galactic and XCOR in the United States, are also trying to commercialize the same reusable technology as the private manned space tourism. Confirmation of these technology trends is essential, because the re-use technology could change the landscape of the global launch vehicle market. 최근 우주 기술이 발달함에 따라 전 세계적으로 위성 시장, 특히 소형 위성 시장이 크게 성장하고 있다. 이러한 위성 시장의 성장세 속에서 발사체 시장 역시 성장세를 보이고 있으며 이에 따라 저비용 발사에 대한 수요가 점점 증가하고 있다. 저비용 발사를 위한 방안에는 저비용 추진제를 사용하는 엔진 개발, 제품 생산 및 운송비용 절감 등 다양한 방법이 존재하지만, 발사 비용을 가장 크게 줄이는 방법은 바로 사용한 발사체를 다시 사용하는 것이다. 재사용 발사체의 시작은 유인 우주선으로 유명한 미국의 Space Shuttle이라 할 수 있다. 하지만 Space Shuttle의 경우 재사용이라고 불리기는 하지만 재사용 할 수 있는 부분이 한정되어 있고, 발사 효율이 떨어져 재사용 발사체 임에도 불구하고 상당히 고비용이었다. 최근에는 미국의 SpaceX와 Blue Origin을 중심으로 상업적 목적의 재사용 발사체가 개발 되고 있고 재착륙 시험에 성공하였다. 뿐만 아니라, SpaceX의 경우 이전 재착륙을 성공한 1단 발사체를 정비하여 다시 발사하는데 까지 성공하기도 하였다. 이러한 추세에 따라 유럽, 인도와 같은 국가에서도 현재 재사용 발사체 연구에 심혈을 기울이고 있다. 그리고 Blue Origin을 포함한 미국의 Virgin Galactic, XCOR 등은 민간 유인 우주여행과 같은 재사용 기술을 이용한 상품화도 시도하고 있다. 재사용 기술이 확립되면 세계 발사체 시장의 판도가 바뀔 수 있기에 재사용 기술 동향의 정기적인 확인은 필수적이라 할 수 있다.

소형발사체 에비오닉스 시스템 설계

윤한수(Hansoo Yun),이현소(Hyunso Lee),최성진(Sungjin Chol),이승희(Seunghee Lee),이창선(Changsun Lee),이강식(Kangsik Lee) 한국추진공학회 2022 한국추진공학회 학술대회논문집 Vol.2022 No.5

국내에서는 나로호, 누리호 등 중형발사체의 개발이 이루어졌으나, 소형발사체는 개발이 시작되는 단계이다. 소형발사체에 적용되는 에비오닉스 시스템의 기능 요구사항은 중형발사체 시스템과 동일하나, 소형발사체의 특성에 따라 중량 절감 및 저비용화 개발이 필수적인 요소이다. 이러한 소형발사체 에비오닉스 시스템의 요구사항을 충족하기 위해 공통 플랫폼 기반 모듈화 설계 및 조합을 통해 장비를 구성함에 따라 소형, 경량화가 가능하며, 다양한 발사체 환경에 적용하기 위해 네트워크 기반의 시스템 설계를 적용하여 유연성을 확보하도록 설계하였다. 또한 발사체의 안전을 담당하는 비행 안전 시스템은 자율 비행 안전 시스템을 적용하여 지상시스템 간소화 및 운영인원의 감축을 통해 운영비용을 절감할 수 있도록 설계함으로서, 소형발사체의 경제적 발사 서비스가 가능한 에비오닉스 시스템을 설계하였다. In Korea, the development of medium-lift launch vehicle was carried out the development of Naro and Nuri, But the development of small launch vehicle is now in the beginning stage. The avionics system of small launch vehicle is not much different from the functions required by medium-lift launch vehicle, but the economical launch service of small launch vehicle requires development by significantly reducing the cost and weight of avionics system compared to medium-lift launch vehicle. To apply the requirement of the avionics system of small launch vehicle, the hardware is designed to develop equipment through a combination of small and lightweight functional modules and to provide flexibility through network-based system design for application to multiple projectiles. The flight safety system, which is responsible for the safety of launch vehicle, is designed to reduce operating costs by reducing ground system and operating personnel by applying an autonomous flight safety system, and thus designed and avionics system capable of economic launch of small launch vehicle.

저비용 우주 발사체 개발 동향 및 이를 위한 차세대 연료에 대한 고찰

배진현(Jinhyun Bae),구자예(Jaye Koo),윤영빈(Youngbin Yoon) 한국항공우주학회 2017 韓國航空宇宙學會誌 Vol.45 No.10

인공위성의 경량화 및 소형화로 인하여 대형발사체보다는 발사 비용이 저렴한 저비용 발사체에 대한 관심이 증가되고 있다. 저비용 발사체의 비용 절감 중 가장 대표적인 방식이 발사체의 재사용이다. 저비용 발사체를 개발하고 있는 대부분의 기업들 역시 발사체 재사용 방식을 채택하고 있다. 이러한 재사용 목적과 더불어 친환경 우주 발사체에 대한 요구가 증가되면서 저비용 발사체에 사용되는 연료의 선택 역시 매우 중요해졌다. 친환경적이면서 발사체의 재사용이 가능하게 하는 연료 중 에너지 밀도 등 다른 요인을 고려했을 때 가장 적합한 것이 메탄이며, 메탄에 수소를 첨가하여 에너지 밀도를 높게 만든 HCNG(hydrogen-enriched compressed natural gas) 역시 적합하다고 판단되었다. 본 연구는 한국형 발사체 개발 이후 국내 우주 개발 방향 설정의 참고자료로써 전 세계 저비용 발사체 동향 및 로켓 연료의 특성에 대해 고찰하였다. Due to the weight reduction and miniaturization of satellites, there is a growing interest in low-cost launch vehicles, which are cheaper to launch than larger launch vehicles. One of the most cost-effective ways to reduce the cost of launch vehicles is the reuse of vehicles. Most companies that are developing low cost launch vehicles are also adopting a vehicles reuse approach. Along with this reuse purpose, the demand for environmentally friendly space launch vehicles has increased, so the choice of fuel used for low cost launch vehicles has also become very important. Methane and hydrogen-enriched compressed natural gas (HCNG), which makes more energy-efficient by adding hydrogen to methane, are considered to be the most suitable when considering other factors such as energy density among the fuels that are eco-friendly and capable of reusing the launch vehicles. This study investigated the trends of low-cost launch vehicle and rocket fuel in the world as a reference for setting up domestic space development after the development of Korea Space Launch Vehicle-II.

Dynamic modeling and structural reliability of an aeroelastic launch vehicle

Pourtakdoust, Seid H.,Khodabaksh, A.H. Techno-Press 2022 Advances in aircraft and spacecraft science Vol.9 No.3

The time-varying structural reliability of an aeroelastic launch vehicle subjected to stochastic parameters is investigated. The launch vehicle structure is under the combined action of several stochastic loads that include aerodynamics, thrust as well as internal combustion pressure. The launch vehicle's main body structural flexibility is modeled via the normal mode shapes of a free-free Euler beam, where the aerodynamic loadings on the vehicle are due to force on each incremental section of the vehicle. The rigid and elastic coupled nonlinear equations of motion are derived following the Lagrangian approach that results in a complete aeroelastic simulation for the prediction of the instantaneous launch vehicle rigid-body motion as well as the body elastic deformations. Reliability analysis has been performed based on two distinct limit state functions, defined as the maximum launch vehicle tip elastic deformation and also the maximum allowable stress occurring along the launch vehicle total length. In this fashion, the time-dependent reliability problem can be converted into an equivalent time-invariant reliability problem. Subsequently, the first-order reliability method, as well as the Monte Carlo simulation schemes, are employed to determine and verify the aeroelastic launch vehicle dynamic failure probability for a given flight time.

Dynamic modeling and structural reliability of an aeroelastic launch vehicle

Pourtakdoust, Seid H.,Khodabaksh, A.H. Techno-Press 2022 Advances in aircraft and spacecraft science Vol.9 No.3

The time-varying structural reliability of an aeroelastic launch vehicle subjected to stochastic parameters is investigated. The launch vehicle structure is under the combined action of several stochastic loads that include aerodynamics, thrust as well as internal combustion pressure. The launch vehicle's main body structural flexibility is modeled via the normal mode shapes of a free-free Euler beam, where the aerodynamic loadings on the vehicle are due to force on each incremental section of the vehicle. The rigid and elastic coupled nonlinear equations of motion are derived following the Lagrangian approach that results in a complete aeroelastic simulation for the prediction of the instantaneous launch vehicle rigid-body motion as well as the body elastic deformations. Reliability analysis has been performed based on two distinct limit state functions, defined as the maximum launch vehicle tip elastic deformation and also the maximum allowable stress occurring along the launch vehicle total length. In this fashion, the time-dependent reliability problem can be converted into an equivalent time-invariant reliability problem. Subsequently, the first-order reliability method, as well as the Monte Carlo simulation schemes, are employed to determine and verify the aeroelastic launch vehicle dynamic failure probability for a given flight time.

발사체 지상고정장치 유압시스템 작동 시험 및 결과 분석

김대래(Dae Rae Kim),양성필(Seong Pil Yang),이재준(Jae Jun Lee),송오섭(Oh-Seob Song),이영신(Young-Shin Lee) 한국추진공학회 2018 한국추진공학회지 Vol.22 No.1

The function of a vehicle holding device (VHD) is to securely hold a launch vehicle on the launch pad and release the launch vehicle at maximum thrust after engine ignition to allow lift-off of the launch vehicle. During the release of the launch vehicle, to prevent the Ka doing a doing a doing mode, which is the vertical oscillation of the entire liquid propellant, the release of the launch vehicle should be gradual. In this study, for the gradual release of a launch vehicle, a hydraulic system comprising an accumulator and pyro valve to operate a hydraulic cylinder and control the speed of the cylinder with an orifice is introduced. Through a test, the influence of design variables on the cylinder speed is analyzed. Based on this, the design values of the hydraulic cylinder are determined. Through this study, the engineering basis for developing a VHD releasing a launch vehicle at maximum thrust is provided.

한국의 우주발사체 산업 발전을 위한 우주발사서비스 시장진입 전략 평가

홍슬기(Seulki Hong),안재명(Jaemyung Ahn) 한국항공우주학회 2015 韓國航空宇宙學會誌 Vol.43 No.10

국가위상 제고와 국내 발사체산업 발전에 따른 경제 발전을 위하여 우주발사서비스 시장진입은 필수적이다. 발사체 개발의 후발주자로써 시장에 효과적으로 진입하기 위해서는 시장의 트렌드를 정확하게 파악하고, 체계적인 시장진입전략을 수립하여야한다. 본 논문에서는 세계 우주발사서비스 시장의 3가지 핵심트렌드(고성능의 대형 우주발사체 수요 증가, 저가형 우주발사체 증가, Dual/Multi-Launch 증가)를 도출하고, 각 핵심트렌드에 대응하기 위한 전략의 우선순위를 쌍대비교분석법을 통해 평가하였다. 그 결과 모든 트렌드 하에서 발사체 신뢰성 확보 전략이 가장 중요하며, 고성능의 대형 우주발사체 수요 증가 트렌드하에서는 정부 지원 전략이, 저가형 우주발사체 및 Dual/Multi-Launch 증가 트렌드 하에서는 가격 경쟁력 확보전략이 두 번째 우선순위를 보였다. This paper suggests the significant strategies and their priority to deal with space transportation market trends. First, market trends related with technical improvement and change in demand are analyzed by the literature research. The three key trends are obtained: ‘Increasing Demand of High-Performance Launch Vehicles’, ‘Rising of Low-Price Launch Vehicles’, and ‘Rising of Dual/Multi-Launch’. And then, strategies for developing the launch vehicle industry in Korea are selected from several studies about commercialization of Korean launch vehicle. The strategies are evaluated by the experts through pairwise comparison matrix and the criteria for this process is how significantly does the strategy effect on the launch vehicle industry through market assessment. As a result, reliable order of priority among the strategies are obtained. Under the three key trends, strategy to enhance reliability is most important. And, strategy to have price competitiveness has secondary priority to deal with ‘Rising of Low-Price Launch Vehicles’ trend and ‘Rising of Dual/Multi-Launch’ trend. On the contrary, strategy of government’s support is secondary under ‘Increasing Demand of High-Performance Launch Vehicles’ trend.

NASA의 발사체 개발과정 연구

정동호,오승협 한국항공우주학회 2011 한국항공우주학회 학술발표회 논문집 Vol.2011 No.4

발사체는 많은 서브시스템으로 구성된 하나의 복잡한 대형 시스템이다. 발사체의 임무 수행을 위해 많은 경험과 시스템 통합 기술이 필요하다. 발사체 개발의 특징과 복잡성은 모두 독특하다. 하지만 발사체를 개발하는 시스템적인 업무체계는 모두 비슷할 것이다. 이 연구에서는 NASA의 발사체 개발과정과 발사체 라이프 싸이클에 근거한 표준화 된 개발과정을 소개한다. 이 개발과정은 발사체 개발 라이프 싸이클을 통해 10단계로 구성된다. A Launch vehicle is one of sophisticated huge system and consists of many sub-systems. A lot of experience and system integration techniques are needed for the launch vehicle to accomplish a mission successfully. The characteristics and complexity in the development of the every launch vehicle is unique. However the systematic work flow for develop launch vehicle is similar to each other. This paper introduces a standardized development process which is based on the whole program life cycles and experiences of NASA on the development of the launch vehicle. The development process can be categorized into 10 phases through the life cycle of the launch vehicle.

발사체 이륙시 엔진최대추력에서 발사체 고정을 해제하는 지상고정장치의 유압시스템 작동 시험 및 특성 분석

김대래(Dae Rae Kim),양성필(Seong Pil Yang),이재준(Jae Jun Lee),김범석(Bum Suk Kim),송오섭(Oh-Seob Song),이영신(Young-Shin Lee) 한국추진공학회 2016 한국추진공학회 학술대회논문집 Vol.2016 No.12

한국형 발사체 지상고정 장치 (Vehicle Holding Device)는 발사체 하부에서 발사체를 고정하는 장치로서 발사체 이륙시 엔진 최대 추력에서 고정을 해제하고 발사체는 이륙한다. 이 과정에서 모든 고정 장치는 동시에 작동하여야 한다. 또한 고정해제시 장치의 고정력을 일시에 제거하는 경우 발사체 추진체가 탱크 내부에서 상하로 진동하는 “카동아동아동 (ka doing a doing a doing mode)” 현상을 유발할 수 있으므로, 점진적으로 고정력을 제거할 수 있는 기능을 필요로 한다. 본 연구에서는 “동시 작동 요구 조건” 및 “점진적 고정해제 요구조건”을 만족하기 위해 설계된, 복잡한 유압기기 없이 추압기 및 파이로 밸브로 유압실린더의 속도를 발생시키고 오리피스에 의해 유압구동기의 속도를 제어하는, 발사체 지상고정장치 유압시스템의 작동 시험을 통하여 운동특성을 분석하고 요구조건을 만족시킬 수 있음을 확인함으로서 최대추력에서 동작할 수 있는 발사체 지상고정 장치의 개발을 위한 공학적 기반을 마련하였다. The responsibility of the vehicle holding device (VHD) for KSLV-II launch vehicle is to hold the launch vehicle securely while it is stayed on launch pad vertically and release launch vehicle safely at maximum thrust after engine ignition to allow a lift-off of launch vehicle. During a release of the holding mechanism of VHD, to prevent the Ka doing a doing a doing mode which is vertical oscillation of entire liquid propellant, gradual release of launch vehicle is required. Also, a release of all VHD should be synchronized very precisely. In this study, to comply the “gradual release and synchronized operation requirement”, a simple and reliable hydraulic system using orifice and pyro valve to control speed of hydraulic cylinder is tested instead of using complicated hydraulic components. As a result, it is verified that hydraulic system meets the requirement. Through this study, engineering basis to develop VHD releaseing launch vehicle at maximum thrust during lift-off is provided.