• 한국항공우주학회지
• /
• 제43권4호
• /
• pp.289-295
• /
• 2015

본 논문은 지상에서 단안 영상센서를 이용하여 항공기의 상대 위치를 측정하는 방법에 대하여 기술하는데, 알고 있는 항공기의 날개전폭과 카메라의 광학 파라미터를 이용하여 상대 거리 및 상대 위치를 측정하는 방법을 제시하였다. 또한 항공기 영상을 추출하기 위하여 차영상 기법을 이용하는 방법을 제시하였다. 이러한 기술은 ILS를 대신할 영상기반 자동착륙 시스템으로 이용될 수 있다. 상대 위치 및 거리 측정 성능을 검증하기 위하여 경비행기와 GPS를 이용하여 성능을 검증하였으며 1.85m의 평균제곱근 오차가 발생함을 확인하였다.

• International Journal of Aeronautical and Space Sciences
• /
• 제18권4호
• /
• pp.740-756
• /
• 2017

This paper proposes a feedback-linearization-based control algorithm for multirotor unmanned aerial vehicles (UAVs). The feedback linearization scheme is highly efficient for considering nonlinearity between the rotational and translational motion of multirotor UAVs. We also propose a dynamic equation that reflects the aerodynamic effects of the vehicles; the equation's parameters can be determined through curve fitting using actual flight data. We derive the feedback linearization controller from the proposed dynamic equation, and propose a Luenberger observer to attenuate measurement noises. The proposed algorithm is implemented using our in-house flight control computer, and we describe its implementation in detail. To investigate the performance of the proposed algorithm, we carry out two flight scenarios: the first scenario, an autonomous landing on a moving platform, is a test of maneuverability; the second, picking up and replacing an object, test the algorithm's accuracy. In these scenarios, the proposed algorithm precisely controls multirotor UAVs, and we confirm that it can be successfully applied to real flight environments.

• 수산해양교육연구
• /
• 제21권3호
• /
• pp.373-389
• /
• 2009

The aims of this study are to examine urgent problems for reorganization into future-proof large purse seine fisheries in order to positively cope with rapidly changing domestic and foreign fisheries circumstances. First, this paper provides current situations of the large purse seine fisheries. The current situations of it are composed of fisheries influence such as vessel number, vessel power, and fisher number, use of resource and fishing places, and changes in products and sales of species caught by the large purse seine. Secondly, this paper reviews current problems of the large purse seine fisheries including cost reduction and increase of value added. Thirdly, this paper suggests basic development direction and countermeasures for strengthening competitiveness of the large purse seine fisheries. In conclusion, urgent problems of the larger purse seine fisheries can be summarized as inefficiency of distribution structures and retarded landing system and facilities as well as the worse of profitability according to shrink of fishing places, reduction of products, lack of workers, and increase in oil price. To solve the urgent problems, the large purse seine fisheries should be changed into an industry with low cost and high efficiency, and also need to introduce of new production system, strengthen autonomous management of natural resource, and increase in value added to products.

• 한국산업융합학회 논문집
• /
• 제27권1호
• /
• pp.77-86
• /
• 2024

Urban Air Mobility (UAM) is considered the future of transportation, offering solutions to urban challenges and reducing environmental issues through the use of electric power and leveraging the sky as a new transportation corridor. UAM has diverse applications, including passenger and goods transportation, emergency rescue operations, patient transfers, and urban tourism. Furthermore, it is poised to revolutionize the transportation landscape, impacting existing infrastructures such as roads and parking lots, along with autonomous vehicles. The UAM industry is anticipated to exert a significant impact on various sectors, including airframe manufacturing, the development of new materials (e.g., fuel cells and batteries), and even the defense industry, resulting in substantial economic benefits. Consequently, conducting proactive research and setting industry standards for UAM takeoff and landing infrastructure is crucial for securing market leadership. In this regard, the case of Pontoise-Cormeiles, France, stands out as it achieved the world's inaugural successful demonstration of a vertiport before the 2024 Olympics. This achievement has significant implications for our preparations for the commercialization of UAMs. Thus, a detailed review of the French vertiport construction case in this study will serve as a foundation for guiding the planning and operation of UAMs in South Korea, particularly in anticipation of upcoming demonstration tests.

• 한국항공우주학회지
• /
• 제38권3호
• /
• pp.228-235
• /
• 2010

본 논문에서는 틸트로터 항공기의 회전익 모드에 대한 자율비행 유도제어 알고리즘을 적응제어기법을 이용하여 설계하는 것이다. 이를 위해 우선 출력기반 근사적 궤환선형화 기법을 통하여 알고리즘의 내부루프를 구성하고 그로부터 발생하는 모델오차를 단일 은닉층-신경망을 적용하여 상쇄하였다. 그리고 리아푸노프 안정성 이론에 따른 적응제어 갱신법칙은 선형 관측기를 기반으로 설계하였다. 나아가 외부루프는 경로점 유도법칙으로부터 생성되는 궤적을 추종하도록 하였으며 특히 엄밀한 자동착륙 궤적추종 성능 향상을 위하여 방향각 및 비행경로각 시선유도법칙을 설계하였다. 틸트로터 비선형 모델 시뮬레이션 결과는 콜렉티브 입력에서 보이는 순간적인 작동기 포화현상 이외에는 만족할 만한 안정성과 추종성능을 보여 주고 있다.

• 제어로봇시스템학회논문지
• /
• 제22권11호
• /
• pp.912-918
• /
• 2016

This paper presents various strategies for humanoid vehicle driving and egress tasks. For driving, a tele-operating system that controls a robot based on a human operator's commands is built. In addition, an autonomous assistant module is developed for the operator. Normal position control can result in severe damage to robots when they egress from vehicles. To prevent this problem, another approach that mixes various joint control techniques is adopted in this study. Additionally, a footplate is newly designed and attached to the vehicle floor for the ground landing phase of the egress task. The attached plate enables the robot to step down onto the ground in a safe manner. For stable locomotion, a balance controller is designed for the humanoid. For the design of the controller, the robot is modeled using an inverted pendulum that consists of a spring and a damper. Then, a state feedback controller (with pole placement and a state observer) is built based on the simplified model. Many approaches that are presented in this paper were successfully applied to a full-sized humanoid, DRC-HUBO+, in the DARPA Robotics Challenge Finals, which were held in the United States in 2015.

• 한국항공우주학회지
• /
• 제50권7호
• /
• pp.479-487
• /
• 2022

본 논문에서는 한국항공대학교에서 연구, 개발한 태양광 무인기 KAU-SPUAV의 자동 비행을 위한 제어기 설계 및 유도기법에 관하여 기술했다. 와류격자법을 활용하여 공력계수들을 계산했고 이를 항공기의 6자유도 방정식에 적용했다. 또한 깃요소이론을 활용하여 프로펠러의 추력 및 토크계수를 계산했다. 상승풍을 맞닥뜨렸을 때 효율적으로 활공하기 위하여 추력을 사용한 고도제어기가 KAU-SPUAV에 사용되었다. 또한 태양광 무인기의 장기체공 임무를 위해 운용 중에 발생하는 바람의 영향을 고려하기 위한 바람 추정 기법을 적용하였고, 강한 맞바람에 대처하기 위한 유도기법과 자동 착륙 알고리즘을 구성하였으며 2021년 8월, 56시간 33분의 태양광 장기체공 실험을 통해 제어 및 유도기법의 성능을 검증하였다.