• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.49 no.7
• /
• pp.557-564
• /
• 2021

This paper describes an automatic landing approach algorithm for fixed-wing UAVs using waypoint guidance. The proposed algorithm utilizes simple 2D Dubin's vehicle pre-simulations in planning the waypoints for landing approach. The remaining time to reach the runway is also estimated in the pre-simulation, and it is used for altitude control. The performance of the designed algorithm was verified by simulations and flight tests.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.42 no.12
• /
• pp.997-1003
• /
• 2014

This paper describes modeling process to obtain precise landing gear model which is necessary to design a control law for ground auto-taxi, auto take-off/landing of UAV. In this paper, landing gear side force modeling is studied to complete a landing gear model of UAV. Side force modeling is performed by calculating cornering angle including steering angle. And ground directional controller is designed by using nose wheel steering and rudder steering at the same time to control course angle error. Accuracy of landing gear side force modeling and ground directional controller is proved by comparing of auto-taxi test results with simulation results.

• Journal of Industrial Convergence
• /
• v.18 no.1
• /
• pp.79-85
• /
• 2020

Recently, the RPAS(Remote Piloted Aircraft System), by remote control and autonomous navigation, has been increasing in interest and utilization in various industries and public organizations along with delivery drones, fire drones, ambulances, agricultural drones, and others. The problems of the stability of unmanned drones, which can be self-controlled, are also the biggest challenge to be solved along the development of the drone industry. drones should be able to fly in the specified path the autonomous flight control system sets, and perform automatically an accurate landing at the destination. This study proposes a technique to check arrival by landing point images and control landing at the correct point, compensating for errors in location data of the drone sensors and GPS. Receiving from the Google Map API and learning from the destination video, taking images of the landing point with a drone equipped with a NAVIO2 and Raspberry Pi, camera, sending them to the server, adjusting the location of the drone in line with threshold, Drones can automatically land at the landing point.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.25 no.6
• /
• pp.536-541
• /
• 2015

In this paper, we propose a the image-based automatic flight control system for the mini drone. Automatic flight system with a camera on the ceiling and markers on the floor and landing position is designed in an indoor environment. Images from the ceiling camera is used not only to recognize the makers and landing position but also to track the drone motion. PC sever identifies the location of the drone and sends control commands to the mini drone. Flight controller of the mini drone is designed using state-machine algorithm, PID control and way-point position control method. From the, The proposed automatic flight control system is verified through the experiments of the mini drone. We see that known makers in environment are recognized and the drone can follows the trajectories with the specific ㄱ, ㄷ and ㅁ shapes. Also, experimental results show that the drone can approach and correctly land on the target positions which are set at different height.

• Journal of Convergence for Information Technology
• /
• v.7 no.3
• /
• pp.27-36
• /
• 2017

In almost industries, such as the logistics industry, marine fisheries, agriculture, industry, and services, small unmanned aerial vehicles are used for aerial photographing or closing flight in areas where human access is difficult or CCTV is not installed. Also, based on the information of small unmanned aerial photographing, application research is actively carried out to efficiently perform surveillance, control, or management. In order to carry out tasks in a mission-based manner in which the set tasks are assigned and the tasks are automatically performed, the small unmanned aerial vehicles must not only fly steadily but also be able to charge the energy periodically, In addition, the unmanned aircraft need to land automatically and precisely at certain points after the end of the mission. In order to accomplish this, an automatic precision landing method that leads landing by continuously detecting and recognizing a marker located at a landing point from a video shot of a small UAV is required. In this paper, it is shown that accurate and stable automatic landing is possible even if simple template matching technique is applied without using various recognition methods that require high specification in using low cost general purpose small unmanned aerial vehicle. Through simulation and actual experiments, the results show that the proposed method will be made good use of industrial fields.

• Journal of the Korea Convergence Society
• /
• v.8 no.6
• /
• pp.9-16
• /
• 2017

Researchers are now faced with a limited flight time of the hoverable UAV due to the sluggish technological advances of the Li-Po energy density and try to find a bypassing solution for the fully autonomous hoverable UAV mission planning. Although there are several candidate solutions, automated wireless charging is the most likely and realistic candidate and we are focusing on the autolanding strategy of the hoverable UAV in this paper since it is the main technology of it. We developed a hoverable UAV flight simulator including Li-Po battery pack simulator using MATLAB/Simulink and UAV flight and battery states are analyzed. The maximum motor power measured as 1,647 W occurs during the takeoff and cell voltage decreases down to 3.39 V during the procedure. It proves that the two Li-Po battery packs having 22 Ah and connected in series forming 12S1P are appropriate for the autolanding mission planning.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.12 no.6
• /
• pp.141-146
• /
• 2012

This paper introduces development of multi-rotor system and vision based autonomous landing system. Multi-rotor platform is modeled by rigid body motion with Newton Euler concept. Also Multi-rotor platform is simulated and tuned by LQR control algorithm. Vision based Autonomous Landing system uses a single camera that is mounted Multi-rotor system. Augmented reality algorithm is used as marker detection algorithm and autonomous landing code is test with GCS for the precision landing.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• v.2
• /
• pp.471-474
• /
• 2006

GPS수신기는 항법센서로서 여러 분야에서 널리 사용되고 있다. 단일 안테나 GPS수신기로부터 일반적으로 위치와 속도 및 시간 정보를 얻을 수 있다. 그러나 고정익 항공기의 운동 특성을 고려하여 단일 안테나 GPS수신기의 측정치로부터 무인항공기의 자세를 추정할 수 있다. 이로써 단일안테나 GPS수신기를 이용하여 무인항공기의 자동 제어가 가능함을 이전 논문에서 보인 바 있다. 본 논문에서는 단일 안테나 GPS수신기를 무인항공기의 기본 센서로 사용하여 자동 이착륙이 가능함을 비행실험을 통해 보인다. 무인항공기의 반응속도와 강건성을 향상시키기 위해 rate gyros의 각속도 측정치를 이용한다. 또한 활주로에 자동착륙하기 위해서는 높은 정확도의 위치 정보가 필요하므로 DGPS를 이용하였다. 비행 실험 동안 무인항공기는 이륙에서 착륙까지 모든 과정을 자동 제어로 수행한다. 대부분 비행은 경로 제어로 이루어진다. 비행 실험 결과를 바탕으로 단일안테나 GPS수신기가 General Aviation 항공기나 무인항공기의 백업이나 저가의 제어 시스템을 위한 주 센서로서 사용이 가능할 것으로 판단된다.

• Journal of Advanced Navigation Technology
• /
• v.17 no.3
• /
• pp.279-284
• /
• 2013

Among the phases of flight operations pilots feel much pressure in landing segment. There is a number of factors affecting landing safety while pilots reduce aircraft speeds and make a touchdown and stop completely. If runway length is sufficient for landing, there maybe is no problem. But it is not the case all the time. So it is necessary to confirm whether landing performance is within limits or not. Required landing distance is actual landing distance demonstrated by flight test pilot plus allowances for average airline pilots. FAR(Federal Aviation Regulations) AFM certification is based upon manual landing for dry and wet runway. Other runway conditions are not the certification basis. JAR dictates even contaminated/slippery runway is included by prescribed allowances. Automatic landing is not certification basis, so actual landing distances are provided. In this paper I would like to analyze distance allowances included in each type of runway condition. In addition there is no regulation about allowances for specific runway condition, I would suggest adequate allowances for that case.

• ICROS
• /
• v.7 no.5
• /
• pp.9-18
• /
• 2001