• 한국군사과학기술학회지
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• 제13권1호
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• pp.67-76
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• 2010

RAM(Reliability, Availability, Maintainability) characteristics of weapon system is a part of Required Operational Capability, must be reasonable and achievable. In this study, we studied the criteria, important factors to establish RAM requirement and reviewed the current process. Then we propose the new process and method to establish the reasonable and achievable RAM requirement by BCS(Baseline Comparison System) model.

• Journal of Astronomy and Space Sciences
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• 제41권1호
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• pp.43-60
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• 2024

Korea Pathfinder Lunar Orbiter (KPLO) is South Korea's first space exploration mission, developed by the Korea Aerospace Research Institute. It aims to develop technologies for lunar exploration, explore lunar science, and test new technologies. KPLO was launched on August 5, 2022, by a Falcon-9 launch vehicle from cape canaveral space force station (CCSFS) in the United States and placed on a ballistic lunar transfer (BLT) trajectory. A total of four trajectory correction maneuvers were performed during the approximately 4.5-month trans-lunar cruise phase to reach the Moon. Starting with the first lunar orbit insertion (LOI) maneuver on December 16, the spacecraft performed a total of three maneuvers before arriving at the lunar mission orbit, at an altitude of 100 kilometers, on December 27, 2022. After entering lunar orbit, the commissioning phase validated the operation of the mission mode, in which the payload is oriented toward the center of the Moon. After completing about one month of commissioning, normal mission operations began, and each payload successfully performed its planned mission. All of the spacecraft operations that KPLO performs from launch to normal operations were designed through the system operations design process. This includes operations that are automatically initiated post-separation from the launch vehicle, as well as those in lunar transfer orbit and lunar mission orbit. Key operational procedures such as the spacecraft's initial checkout, trajectory correction maneuvers, LOI, and commissioning were developed during the early operation preparation phase. These procedures were executed effectively during both the early and normal operation phases. The successful execution of these operations confirms the robust verification of the system operation.

• 한국항공우주학회지
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• 제48권6호
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• pp.455-466
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• 2020

본 연구에서는 다수의 우주 환경 관측용 탑재체를 장착한 6U급 초소형위성에 대한 열모델을 구축하여 이를 기반으로 수행된 열설계에 대해 기술하였으며, 궤도 열해석을 통해 적용된 열설계의 유효성을 입증하였다. 초소형위성의 특성을 고려하여 표면 처리 및 절연체, 열전도체 등의 수동 열제어 기법 위주로 열설계를 진행하였지만, 배터리 및 추력기 등과 같이 작동 온도의 범위가 좁고 궤도 열환경에 직접적으로 노출되는 부품들에 대해서는 능동 열제어 기법 중 하나인 히터를 적용하였다. 궤도 열해석 조건은 기본적으로 위성의 궤도 조건을 바탕으로 하며, 임무 시나리오에 따른 발열량 및 위성의 자세에 따라 임무 모드, 초기 운용 모드, 비상운용 모드, 편대 비행 모드로 분류하여 궤도 열해석을 수행하였다. 각 모드 별 해석 결과를 통해 모든 부품들이 작동 온도 조건을 만족하는 것을 확인하였고, 비상운용 모드의 해석 결과를 통해 배터리 및 추력기의 히터 용량과 작동 주기를 산출하였다.

• 제어로봇시스템학회논문지
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• 제16권9호
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• pp.905-912
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• 2010

Modern version of advanced supersonic fighter have ATCS (Automatic Thrust Control System) to maximum flight safety, fuel efficiency and mission capability the integrated advanced autopilot system such as TFS (Terrain Following System), GCAS (Ground Collision Avoidance System) and AARS (Automatic Attitude Recovery System) and etc. This paper addresses the design and verification of ATCS based on advanced supersonic trainer in HILS (Hardware In the Loop Simulator) with minimum hardware modification to reduce of development cost and maintain of system reliability. The function of ATCS is consisted of target speed hold mode in UA (Up and Away) and angle of attack hold mode in PA (Power Approach). The real-time pilot evaluation reveals that pilot workload is minimized in cruise and approach flight stage by ATCS.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.800-803
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• 2006

The Space-borne electro-optical camera system, like KOMPSAT has panchromatic redundant image channel as well as primary channel in order to increase reliability of satellite system. In most case redundant channel never been used during the whole mission period. Staggered array configuration using redundant image channel and new operation mode proposed which operates primary and redundant channel simultaneously. Without new hardware design, fast electronics and system complexity, we can get 1.414 times more fine GSD image of original system and aliasing effect which corrupt high frequency information of image can be minimized. To get the more efficiency from staggered array configuration, we introduce masked pixel CCD.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.2108-2111
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• 2005

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 point Mode of KOMPSAT-2. The performance of this fuzzy controller design is compared with that of PD controller used for KOMPSAT-2.

• 한국군사과학기술학회지
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• 제15권1호
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• pp.9-15
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• 2012

This paper shows an effective scanning trajectory for a mine detection device that is one of the mission equipments of unmanned ground vehicle. The mine detection device is composed of a mine-detection sensor, and a 4 DOF manipulator enabling sensor position control. There are three modes that manage the mine detection device: passive, semi-automatic, and automatic. The automatic mode is used the most. This paper suggests a scanning method that makes shape of 8. This method prevents missing target area and enhances scanning speed when the mine detection device scans the ground surface in automatic mode. The suggested method is verified by simulations and experiments.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.203-206
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• 2007

The Space-borne electro-optical camera system has panchromatic redundant image channel as well as primary channel in order to increase reliability of satellite system. In most case redundant channel never been used during the whole mission period. Staggered array configuration using redundant image channel and new operation mode proposed which operates primary and redundant channel simultaneously. Without new hardware design, fast electronics and system complexity, we can get 1.414 times more fine GSD image of original system or we can get 1.414 times more SNR or High dynamic range imaging mode. In this paper we deal with several image quality improvement methods using dual panchromatic channel.

• 항공우주시스템공학회지
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• 제12권3호
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• pp.45-52
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• 2018

본 논문에서는 현재 대표적으로 사용되고 있는 멀티콥터 오픈소스 기반 비행제어 컨트롤러인 Pixhawk의 내부루프 알고리즘 분석에 대해 연구한 내용을 다룬다. Pixhawk의 내부루프 알고리즘은 위치제어기, 자세제어기로 나눌 수 있는데, 위치 제어기는 목표로 이동하기 위한 멀티콥터의 자세를 제시하며 자세제어기는 원하는 자세로 변할 수 있도록 구동기에 작용하는 요구 추력과 모멘트 변화를 발생시킨다. 여기서 위치제어기는 멀티콥터의 급격한 자세변화를 방지하기 위해 적절한 관계식을 이용하여 요구 가속도 및 속도에 대해 제한을 하고 있는 것을 확인 할 수 있다.

• 한국항행학회논문지
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• 제26권5호
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• pp.358-364
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• 2022

항공용 인터콤 시스템은 정/부조종사 간 내부 통화 및 조종사와 승무원 간 내부 통화, 초고주파 무전기(U/VHF)와 같은 통신 장비를 통한 외부 통화, 초단파전방향거리탐지기/계기착륙장치(VOR/ILS), 전술 항법 장치(TACAN)와 같은 항법 및 임무 장비 오디오 신호 모니터링, 비행 데이터기록장치(FDR) 및 자료전송 시스템(DTS)으로의 음성 녹음용 오디오 신호 출력, 항공기의 상태와 위협 등에 대한 오디오 경고음/경고 음성 발생 등 항공기 내의 모든 음성 신호에 대한 처리를 담당하는 장비이다. 이러한 항공용 인터콤은 아날로그 오디오 신호의 경우 노이즈에 민감하기 때문에 조종사 및 승무원의 임무 수행을 위해 항공기 내/외부의 전자파 노이즈로부터 오디오 신호를 보호할 수 있는 이중화 설계가 필요하다. 본 논문에서는 항공용 디지털 인터콤의 이중화를 위한 정상/백업 운용모드 및 디지털 방식의 이중화 설계 방안과 제작 및 검증 결과에 대하여 기술한다.