• 한국항행학회논문지
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• 제28권3호
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• pp.375-378
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• 2024

The instrument landing system (ILS) is an international standard established by the International civil aviation organization (ICAO) as one of the landing support facilities for aircraft. This system consists of a localizer (LOC) that provides orientation information about the runway to indicate the approach direction, a glide path (GP) that indicates the appropriate approach glide slope, and three of marker beacons (MB) that indicates the distance to the runway landing edge. In this study, we predicted the received signal strength by altitude and distance for LOC signals transmitted from the ground and analyzed the difference with the signal strength measured in the actual environment. Our objective is to develop signal strength prediction technology and apply it to the real environment.

• 대한물리의학회지
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• 제6권2호
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• pp.145-151
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• 2011

Purpose: The study was designed to investigate the effects of landing heights on muscle activities and ground reaction force during drop landing. Methods: Sixteen healthy adults were recruited along with their written informed consent. They performed a drop-landing task at the height of 20, 40, and 60cm. They completed three trials in each condition and biomechanical changes were measured. The data collected by each way of landing task and analyzed by One-way ANOVA. Ground reaction forces were measured by force flate, muscle activities measured by MP150 system. Results: There were significant differences in ground reaction forces, and significant increases in muscle activities of tibialis anterior, medial gastrocnemius and biceps femoris with landing heights. Conclusion: These findings revealed that heights of landing increases risk factors of body damage because of biomechanical mechanism and future studies should focus on prevention from damage of external conditions.

• 대한임베디드공학회논문지
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• 제18권2호
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• pp.75-80
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• 2023

Unmanned drone stations for automatic charging have been developed in order to overcome the flying time limitation of rotary wing drones. Since the drone stations is an unmanned operating system, each of the drones will be required to have a high degree of landing accuracy. Drone precision landing has been mainly studied depended on image processing technologies, but the image processing systems make several problems, such as the mission weight, the drone cost, and the development complexity increases, and the flight time decrease. Thus, this paper researched accuracy of precision landing based on RTK (real time kinetics) for rotary wing drones. For the experiments of RTK based precision landing, a drone repeatedly performed three missions. The survey accuracies of the RTK about missions respectively were set as 0.3, 0.2, and 0.1 meters. Each mission has one take-off point, two way-points and one landing-point, and was repeated ten times. The experiment results revealed landing error distance means of around 0.258, 0.12 and 0.057 meters on each of RTK setting.

• 한국군사과학기술학회지
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• 제14권5호
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• pp.788-797
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• 2011

This paper analyzes the accuracy on the approach and landing of aircraft to an airport through comparison with airbase Precision Approach Radar and aircraft track data of DGPS equipped in aircraft. The proposed analysis result could be a basis for verifying the possibility that DGPS can be utilized in Airbase precision approach and landing. Position identification capability of widely used commercial DGPS is fairly accurate on latitude and longitude, while there is a slight error for being used in an airbase accurate approach and landing of Category I precision when it comes to altitude. Thus, we tested accuracy by analyzing actual flight track data of high performance aircraft to verify the accuracy of the airbase approach and landing using DGPS. Through the research, we developed instrumentation to compare PAR track data with DGPS track data, which can be used in reducing the number of PAR verification Flight utilizing it as a system measuring PAR accuracy at PAR installation phase.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1228-1233
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• 2005

In this paper, we present a new guidance law for a reusable launch vehicle (RLV) that lands vertically after reentry. In our past studies, a guidance law was developed for a vertical/soft landing to a target point. The guidance law, which is analytically obtained, can regenerate a trajectory against disturbances because it is expressed in the form of state feedback. However, the guidance law does not necessarily guarantee a vertical/soft landing when a dynamical system such as an RLV includes a nonlinear phenomenon owing to the atmosphere of the earth. In this study, we introduce a design of the guidance law for a nonlinear system to achieve a vertical/soft landing on the ground using the exact linearization method and solving the two-point boundary-value problem for the derived linear system. Numerical simulation confirmed the validity of the proposed guidance law for an RLV in an atmospheric environment.

• 제어로봇시스템학회논문지
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• 제20권11호
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• pp.1085-1091
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• 2014

This paper presents the guidance and control design for automatic carrier landing of a UAV (Unmanned Aerial Vehicle). Differently from automatic landing on a runway on the ground, the motion of a carrier deck is not fixed and affected by external factors such as ship movement and sea state. For this reason, robust guidance/control law is required for safe shipboard landing by taking the relative geometry between the UAV and the carrier deck into account. In this work, linear quadratic optimal controller and longitudinal/lateral trajectory tracking guidance algorithm are developed based on a linear UAV model. The feasibility of the proposed control scheme and guidance law for the carrier landing are verified via numerical simulations using X-Plane and Matlab/simulink.

• 제어로봇시스템학회논문지
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• 제14권12호
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• pp.1253-1259
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• 2008

This paper presents a landing controller and guidance law for net-recovery of fixed-wing unmanned aerial vehicles. A linear quadratic controller was designed using the system identification result of the unmanned aerial vehicle. A pursuit guidance law is applied to guide the vehicle to a recovery net with imaginary landing points on the desired approach path. The landing performance of a pure pursuit guidance, a constant pseudo pursuit guidance, and a variable pseudo pursuit guidance is compared. Numerical simulation using an unmanned aerial vehicle model was performed to verify the performance of the proposed landing guidance law.

• 대한기계학회논문집A
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• 제38권3호
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• pp.303-308
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• 2014

오늘날 비행기는 없어서는 안 되는 교통수단 중의 하나이다. 비행기는 교통 수단 뿐 만 아니라 여러 분야에서 널리 사용되고 있다. 예를 들어, 사람을 태우고, 짐을 실어 나르고, 군에서는 정찰 등의 임무를 수행하게 된다. 지상에서 이륙 착륙이 이루어 진다. 이륙할 때 보다는, 착륙할 시 랜딩기어에 많은 하중이 작용하게 된다. 착륙장치는 충격 에너지를 흡수하며, 사고 시에 동체가 파손되지 않도록 방지한다. 본 논문에서는 복합재와, 알루미늄을 적용한 판 스프링형 랜딩기어에 대하여 시뮬레이션을 수행하였다. 두 가지 재료의 랜딩기어에 대한 구조적 안전성이 평가되었다.

• 대한의용생체공학회:의공학회지
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• 제32권2호
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• pp.105-108
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• 2011

The purpose of the present study was to analyze the lower stiffness over the difference between soft and stiff landings during hopping. Five male subjects performed hopping on two legs at 2.5 Hz. During the experiments, 3D motion capture system was used to obtain the kinematic data and two force plates were synchronized to calculate the kinetic data. We determined lower extremity stiffness of the knee and ankle from kinetic and kinematic data. Leg stiffness was approximately 1.2-times significantly higher in stiff landing than in soft landing_ There was no significant difference in knee joint stiffness between soft and stiff landings. Ankle joint stiffness was approximately 1.34-times significantly higher in stiff landing than in soft landing. These results suggest that humans adjust lower extremity stiffness over the comparison of two different landing methods we evaluated.

• 한국항공우주학회지
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• 제36권11호
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• pp.1121-1125
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• 2008

본 논문에서는 소형 항공기 낙하시험을 위한 낙하 시험 장비 개발에 관한 연구를 수행하였다. 시험장비는 유압 액츄에이터를 이용하여 자동으로 시험체를 상승시키고 또 다른 유압 액츄에이터를 이용 자동으로 낙하시키며, 낙하시험시 안전성 확보를 위한 2중의 안전 장치를 적용하였다. 장비의 정적 안정성 확보를 위해 장비의 구조해석을 수행하였으며, 해석된 결과를 반영하여 시험 장비를 설계 제작을 하였다. 제작된 장비의 낙하 신뢰도 확보를 위해 마찰력 측정 시험 및 낙하속도 측정 시험을 실시하여 장비의 적합성을 확인 하였다.