• International Journal of Aeronautical and Space Sciences
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• 제8권1호
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• pp.46-53
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• 2007

In this paper, a guidance law for vision-based automatic landing of unmanned aerial vehicles (UAVs) is proposed. Automatic landing is a challenging but crucial capability for UAVs to achieve a fully autonomous flight. In an autonomous landing maneuver of UAVs, the decision of where to landing and the generation of guidance command to achieve a successful landing are very significant problem. This paper is focused on the design of guidance law applicable to automatic landing problem of fixed-wing UAV and rotary-wing UAV, simultaneously. The proposed guidance law generates acceleration command as a control input which derived from a specified time-to-go ($t_go$) polynomial function. The coefficient of $t_go$-polynomial function are determined to satisfy some terminal constraints. Nonlinear simulation results using a fixed-wing and rotary-wing UAV models are presented.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2345-2348
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• 2003

This paper deals with a problem of automatic landing guidance and control system design. The auto-landing control system for the longitudinal motion is designed in the classical PID controller. The controller gains are properly adapted to variation of the performance using fuzzy logic as a gain scheduler for the PID gains. This control logic is applied to the problem of the automatic landing control system design. From the numerical simulation using the 6DOF nonlinear model of the associated airplane, it is shown that the auto-landing maneuver is successfully achieved from the start of the flight conditions: 1500 ft altitude, 250 ft/sec airspeed and zero flight path angle.

• 항공우주시스템공학회지
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• 제18권2호
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• pp.47-55
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• 2024

공중 무인 이동체(UAV)인 드론을 해상 무인 이동체(USV)와 자율 협력하여 임무를 수행하기 위해선 자동 착륙 시스템이 필요하다. 본 논문에서는 피라미드 형상의 착륙 장치와 패드를 기반으로 한 도킹 방식의 자동 착륙 시스템을 제안하였다. 파도, 바람 등 해상 환경에 의해 영향을 받더라도 드론이 착지할 수 있도록 유도하고, 결합(Docking) 장치를 통해 순간적으로 고정할 수 있다. 3-DoF 모션 플랫폼으로 함상의 거동을 모사하여 착륙 시험을 수행하였으며, 도킹 방식 자동 착륙 시스템의 운용·활용 가능성을 확인하였다.

• 한국항공우주학회지
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• 제30권5호
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• pp.41-47
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• 2002

본 논문에서는 일반항공기나 무인항공기의 자동착륙에 적용할 수 있는 착륙 유도 법칙을 제안하고 기존의 일반적인 착륙 과정과의 비교를 통하여 성능을 확인하였다. 착륙 유도법칙은 미사일 요격에서 사용되는 Miss distance 개념과 Lyapunov 안정성 이론에 근거하여 궤환 형태의 속도 및 비행 경로각 명령을 생성할 수 있도록 구성하였다. 기존 문헌에 제시된 항공기의 자동착륙 시뮬레이션을 이용하여 착륙 접근 및 착지 기동 과정을 모사하였다. 착륙 접근의 제U 목적인 강하로 이탈 거리 제거와, 착지 기동시 제어 목적인 고도 제어의 관점에서 새로이 제안하고 있는 착륙 유도 법칙은 기존 방법에 대등 또는 우수한 결과를 얻을 수 있었다. 기준 궤적의 설정에 따라 다양한 비행 궤적 추종이 가능하므로 향후 무인기의 자동 착륙이나 기동 비행의 설계시 적용할 수 있을 것이다.

• International Journal of Aeronautical and Space Sciences
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• 제5권1호
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• pp.30-38
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• 2004

This paper deals with a problem of automatic landing guidance and control ofthe longitudinal airplane motion under the wind shear turbulence. Adaptive gainscheduled PID control law is proposed in this paper. Fuzzy logic is the main part ofthe adaptive PID controller as gain scheduler. To illustrate the successful applicationof the proposed control law to the automatic landing control problem, numericalsimulation is carried out based on the longitudinal nonlinear airplane model excited bythe wind shear turbulence. The simulation results show that the automatic landingmaneuver is successfully achieved with the satisfactory performance and the gainadaptation of the control law is made adequately within the limited gains.

• 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.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1688-1692
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• 2003

The automatic Landing system is used for the automatic functions of automatic transfer crane in the automated container terminal. It confirms and adjusts the alignment and pose between spreader and container and accomplishes the automatic loading/unloading job of containers in yard. Specially, it is required in the automated container terminal and is well adapted under the coarse external environments. This system used the laser sensors to recognize the alignment between spreader and container. In this paper the algorithm of recognition of the alignment and pose is presented and the result of its simulation is shown.

• 제어로봇시스템학회논문지
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• 제15권1호
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• pp.54-60
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• 2009

In this paper, a precision landing approach is implemented based on real-time image processing. A full-scale landmark for automatic landing is used. canny edge detection method is applied to identify the outside quadrilateral while circular hough transform is used for the recognition of inside circle. Position information on the ground landmark is uplinked to the unmanned helicopter via ground control computer in real time so that the unmanned helicopter control the air vehicle for accurate landing approach. Ground test and a couple of flight tests for autonomous landing approach show that the image processing and automatic landing operation system have good performance for the landing approach phase at the altitude of $20m{\sim}1m$ above ground level.

• 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.

• 한국항공우주학회지
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• 제49권7호
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• pp.557-564
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• 2021

본 논문에서는 고정익 무인기의 점항법을 이용한 자동 착륙 접근 유도에 대해 기술한다. 본 연구의 주요 특징은 Dubin's 모델 기반 2D 사전 시뮬레이션을 이용하여 자동 착륙 접근에 필요한 경로점을 생성하고, 또한 사전 시뮬레이션으로부터 활주로까지의 남은 시간을 예측하여 이를 고도 제어에 활용한다. 설계한 알고리즘의 성능은 시뮬레이션과 비행 시험을 통해 검증한다.