• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.37 no.8
• /
• pp.798-804
• /
• 2009

A high-resolution electro-optical camera system, EOS-C, is under development in Satrec Initiative. This system is the mission payload of a 400-kg Earth observation satellite. We designed this system to give improved opto-mechanical and thermal performance compared with a similar camera system to be flown on the DubaiSat-1 system. The thermal control subsystem (TCS) of the EOS-C system uses heaters to meet the opto-mechanical requirements during in-orbit operation and it uses different thermal coating materials and multi-layer insulation (MLI) blankets to minimize the heater power consumption. We performed its thermal analysis for the mission orbit using a thermal analysis model and the result shows that its TCS satisfies the design requirements.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2009.10a
• /
• pp.239-242
• /
• 2009

Power Control and Distribution Unit (PCDU) plays roles of power generation control for solar array panel, power storage control for battery system, power conversion for unregulated and regulated primary bus and power distribution to bus and payload system. The selection and design of the proper auxiliary power interface for PCDU depending on various mission is one of the most important step for electrical power subsystem design. In this paper, the general design approach of auxiliary power interface for PCDU which can be used for small-sized LEO satellites application is given. And, the auxiliary power design concept for always alived modules such as solar array regulator and house keeping module is also suggested.

• Journal of Institute of Control, Robotics and Systems
• /
• v.10 no.6
• /
• pp.557-565
• /
• 2004

The Korean space program was marked by the successful launching of a KSR-III liquid propelled sounding rocket. The Inertial Navigation System (INS) which carries out critical mission functions of navigation, guidance and control was domestically developed and perfectly certified through the flight test. The system consists of a strapdown inertial measurement, an onboard computer and flight software. This paper will describes the development works of the inertial navigation system, including top level system design, hardware and software. And it summarizes flight results.

• The Journal of Korea Robotics Society
• /
• v.3 no.2
• /
• pp.106-111
• /
• 2008

This paper presents a decentralized coordination for a small-scale mobile robot teams performing a task through cooperation. Robot teams are required to generate and maintain various geometric patterns adapting to an environment and/or a task in many cooperative applications. In particular, all robots must continue to strive toward achieving the team's mission even if some members fail to perform their role. Toward this end, given the number of robots in a team, an effective coordination is investigated for decentralized formation control strategies. Specifically, all members are required first to reach agreement on their coordinate system and have an identifier (ID) for role assignment in a self-organizing way. Then, employing IDs on individual robots within a common coordinate system, a decentralized neighbor-referenced formation control is realized to generate, keep, and switch between different geometric shapes. This approach is verified using an in-house simulator and physical mobile robots. We detail and evaluate the formation control approach, whose common features include self-organization, robustness, and flexibility.

• Journal of the Society of Disaster Information
• /
• v.6 no.1
• /
• pp.46-59
• /
• 2010

In this study, the safety training of comparative analysis of the realities of Korea's safety training and international experience and practical training for the safety experience of a virtual reality simulator, the development of safe conduct as a controlled motion simulator system, image H / W and the control system works, sound effects H / W and the control system works, 4D special effects (smoke, heat, wind, vibration) and a control system integration, mission control system for the selection and evaluation of the proposal, and safety training on Game S / W of development as we have never experienced an earthquake action plan and evacuate to escape the power of experience and the experience of an earthquake (vibration + video), Also the collapse and a fire escape on the experience of following second disaster, the building collapsed during an escape experience in the field, in case of fire According to the initial fire suppression and fire extinguisher usage experience - experience of smoke and heat to escape in, Moreover, the Daegu subway fire in public places such as subway and evacuated to escape the experience, considering the suggested Simulator.

• Journal of Aerospace System Engineering
• /
• v.3 no.4
• /
• pp.7-10
• /
• 2009

The driver's speed control to the satellite's mission is required. Therefore, optimal control over the value of benefits is required. Driver to control the characteristics of the driver and the driver was analyzed. Experimental results based on the estimated parameters using the equations of motion and was passed to save the function. Using optimization techniques applied to estimate the proportional term gain was the result of the analysis.

• Journal of Advanced Engineering and Technology
• /
• v.11 no.4
• /
• pp.273-277
• /
• 2018

In the field of forest disaster prevention, drones are expected to save higher human resources than the existing manpower has, and produce high-efficiency results over time. However, operational limitations brought by short flight times have brought the environment of limited use of the various capabilities of the drone, and the existing development systems operating the multi-drone are mainly for performance purpose, so it is a difficult to use for forest disaster prevention. The purpose of this paper is to design the concept based on multi-drone operation procedure through analysis of mission of ground control system for forest disaster prevention.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.21 no.4
• /
• pp.409-420
• /
• 2015

In this study, I researched, analysed and compared the examples of civilian maritime search and rescue auxiliaries of world leading countries' such as Japan and America, and the Korean volunteer fire fighting team. Through this, I suggest that the decentralized civilian maritime search and rescue forces of Maritime Rescue and Salvage Association and KCG Civilian Auxiliary should be united into unified search and rescue system and establish legal basis for stabilized support and development. It seem that we should organize laws and regulations for the government to have centralized control of rescue mission as in the cases of America and Canada and elivate rescue mission capability with systemized education and training entrusted to specialized external training organization. I proposed to establish financial support such as fund for the stabilized status of civilian auxiliary, domestic and overseas training session for the civilian auxiliary to inspire integrity and sense of duty as a part of maritime search and rescue forces.

• Bulletin of the Korean Space Science Society
• /
• 2011.04a
• /
• pp.24.4-24.4
• /
• 2011

Frozen orbit concept is very useful in designing particular mission orbits including the Sun-synchronous and minimum altitude variation orbits. In this work, variety of frozen and Sun-synchronous orbit conditions around the Moon is investigated and analyzed. The first two zonal harmonics of the Moon, J2 and J3, are considered to determine mean orbital elements to be a frozen orbit. To check the long-term behavior of a frozen orbit, formerly developed YonSei Precise Lunar Orbit Propagator (YSPLOP) is used. First, frozen orbit solutions without conditions to be the Sun-synchronous orbit is investigated. Various mean semi-major axes having between ranges from 1,788 km to 1,938 km with inclinations from 30 deg to 150 deg are considered. It is found that a polar orbit (90 deg of inclination) having 100 km of altitude requires the orbital eccentricity of about 0.01975 for a frozen orbit. Also, mean apolune and perilune altitudes for this case is about 136.301 km and 63.694 km, respectively. Second, frozen orbit solutions with additional condition to be the Sun-synchronous orbit is investigated. It is discovered that orbital inclinations are increased from 138.223 deg to 171.553 deg when mean altitude ranged from 50 km to 200 km. For the most usual mission altitude at the Moon (100 km), the Sun-synchronous orbit condition is satisfied with the eccentricity of 0.01124 and 145.235 deg of inclination. For this case, mean apolune and perilune altitudes are found to be about 120.677 km and 79.323 km, respectively. The results analyzed in this work could be useful to design a preliminary mapping orbit as well as to estimate basic on-board payloads' system requirements, for a future Korea's lunar orbiter mission. Other detailed perturbative effects should be considered in the further study, to analyze more accurate frozen orbit conditions at the Moon.

• International Journal of Aeronautical and Space Sciences
• /
• v.17 no.4
• /
• pp.622-630
• /
• 2016

In the operation of a low earth orbit satellite, a series of antenna commands are transmitted from a ground station to the satellite within a visibility window (i.e., the time period for which an antenna of the satellite is visible from the station) and executed to control the antenna. The window is a limited resource where all data transmission is carried out. Therefore, minimizing the transmission time for the antenna commands by reducing the data size is necessary in order to provide more time for the transmission of other data. In this paper, we propose a geometric compression method based on B-spline curve fitting using dominant points in order to compactly represent the antenna commands. We transform the problem of command size reduction into a geometric problem that is relatively easier to deal with. The command data are interpreted as points in a 2D space. The geometric properties of the data distribution are considered to determine the optimal parameters for a curve approximating the data with sufficient accuracy. Experimental results demonstrate that the proposed method is superior to conventional methods currently used in practice.