• International Journal of Automotive Technology
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• 제7권1호
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• pp.83-90
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• 2006

The purpose of this paper is to describe the design and implementation of an unmanned ground vehicle, called the TailGator at CIMAR (Center for Intelligent Machines and Robotics) of the University of Florida. The TailGator is a gas powered, four-wheeled vehicle that was designed for the AUVSI Intelligent Ground Vehicle Competition and has been tested in the contest for 2 years. The vehicle control model and design of the sensory systems are described. The competition is comprised of two events called the Autonomous Challenge and the Navigation Challenge: For the autonomous challenge, line following, obstacle avoidance, and detection are required. Line following is accomplished with a camera system. Obstacle avoidance and detection are accomplished with a laser scanner. For the navigation challenge, waypoint following and obstacle detection are required. The waypoint navigation is implemented with a global positioning system. The TailGator has provided an educational test bed for not only the contest requirements but also other studies in developing artificial intelligence algorithms such as adaptive control, creative control, automatic calibration, and internet-base control. The significance of this effort is in helping engineering and technology students understand the transition from theory to practice.

• 제어로봇시스템학회논문지
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• 제20권2호
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• pp.138-142
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• 2014

This research presents an A* based algorithm which can be applied to Unmanned Ground Vehicle self-navigation in order to make the driving path smoother. Based on the grid map, A* algorithm generated the path by using straight lines. However, in this situation, the knee points, which are the connection points when vehicle changed orientation, are created. These points make Unmanned Ground Vehicle continuous navigation unsuitable. Therefore, in this paper, B-spline curve function is applied to transform the path transfer into curve type. And because the location of the control point has influenced the B-spline curve, the optimal control selection algorithm is proposed. Also, the optimal path tracking speed can be calculated through the curvature radius of the B-spline curve. Finally, based on this algorithm, a path created program is applied to the path results of the A* algorithm and this B-spline curve algorithm. After that, the final path results are compared through the simulation.

• 제어로봇시스템학회논문지
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• 제18권4호
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• pp.359-364
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• 2012

Real-Time Traversability should be analyzed from the equiped sensors' data in real time for autonomous outdoor navigation. However, it is difficult to find out such traversability that considers the terrain roughness and the vehicle dynamics especially in case of skid type vehicle. The traversability based on real time dynamic analysis was proposed to solve such problem but in navigation with strait driving path. To adapt the method into the navigation with curved driving path, a path following controller should be incorporated into the dynamic model even though it cause the real time problem. In this paper, a dynamic model is proposed to solve the real time problem in the traversability analysis based on real time dynamic simualtion. The dynamic model contains the control dummy which is connected to the vehicle body with a universal joint to follow the curved path without controller. Simulation and experimental results on $6{\times}6$ articulated unmanned ground vehicle demonstrate the method's effectiveness and applicability into the traversability analysis on terrain with bumps.

• 한국군사과학기술학회지
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• 제17권6호
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• pp.810-820
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• 2014

Recently many studies of Radar systems mounted on ground vehicles for autonomous driving, SLAM (Simultaneous localization and mapping) and collision avoidance are reported. In near field, several hits per an object are generated after signal processing of Radar data. Hence, clustering is an essential technique to estimate their shapes and positions precisely. This paper proposes a method of grouping hits in range-doppler domains into clusters which represent each object, according to the pre-defined rules. The rules are based on the perceptual cues to separate hits by object. The morphological connectedness between hits and the characteristics of SNR distribution of hits are adopted as the perceptual cues for clustering. In various simulations for the performance assessment, the proposed method yielded more effective performance than other techniques.

• 한국멀티미디어학회논문지
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• 제20권3호
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• pp.437-445
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• 2017

Necessity of security reinforcement has been increased these days. As a result, surveillance systems using CCTV and the patrol system by person have been applied to security zone. However, CCTV has a blind spot and CCTV itself cannot handle emergency situation. Patrol system by person is economically expensive. To overcome these disadvantages, this paper presents an image-based surveillance system using unmanned aircraft. As a default, unmanned aircraft traces lines installed on ground which represents path for patrolling. If the aircraft detects objects, then it keeps a constant distance between object without missing the object in the image. Simulation results show that the proposed system can be operated even with unmanned aircraft with low specification.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.367-371
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• 2004

This paper describes development of automatic flight control system for an unmanned target drone which is operated by Korean army as for anti-air gun shooting training. Current target drone is operated by pilot control of on-board servo motor via remote control system. Automatic flight control system for the target drone greatly reduces work load of ground pilot and can increase application area of the drone. Most UAVs being operated now days use high-priced sensors as AHRS and IMU to measure the attitude, but those are costly. This paper introduces the development of low-cost automatic flight control system with low-cost sensors. The integrated automatic flight control system has been developed by integrating combining power module, switching module, monitoring module and RC receiver as an one module. The performance of automatic flight control system is verified by flight test.

• International Journal of Aeronautical and Space Sciences
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• 제8권2호
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• pp.54-66
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• 2007

Traffic and emergency monitoring systems are essential constituents of Intelligent Transportation System (ITS) technologies, but the lack of traffic monitoring has become a primary weakness in providing prompt emergency services. Demonstrated in numerous military applications, unmanned aerial vehicles (UAVs) have great potentials as a part of ITS infrastructure for providing quick and real-time aerial video images of large surface area to the ground. Despite of obvious advantages of UAVs for traffic monitoring and many other civil applications, it is rare to encounter success stories of UAVs in civil application including transportation. The objective of this paper is to report the outcomes of research supported by the state agency in US to investigate the feasibility of integrating UAVs into urban highway traffic monitoring as a part of ITS infrastructure. These include current technical and regulatory issues, and possible suggestions for a future UAV system in civil applications.

• 항공우주기술
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• 제3권1호
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• pp.9-15
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• 2004

본 논문에서는 무인비행선 비행제어시스템의 HILS(Hardware-In-the-Loop-Simulation) 시스템 개발 결과를 소개한다. HILS 시스템은 비행선 제어를 위해 설계된 비행제어컴퓨터의 지상시험을 위해 개발되었다. HILS 시스템을 구성하기 위해 각각 별도의 컴퓨터에서 작동하는 통신장비 모사 시스템, 탑재장치 모사 시스템, 비행선 운동 모사 시스템, 그리고 운동 가시화 시스템을 개발하였고, 이와 함께 3축 운동 시험대와 관성항법장치(Inertial Navigation Unit)도 포함하였다. 개발된 HILS 시스템을 이용한 단계적인 시험을 통해 비행 제어컴퓨터의 기능과 성능을 검증하였다.

• 전자공학회논문지
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• 제50권9호
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• pp.46-51
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• 2013

본 논문에는 무인항공기에 장착된 UHF 안테나의 최적 위치 및 형상이 다양한 위치에서 EM 시뮬레이션을 통하여 분석되어져 있다. EM 시뮬레이션을 위하여 FEKO를 이용하였다. 시뮬레이션의 복잡도를 줄이고 분석시간과 메모리 이용도를 최소화하기 위하여 비행체의 복합체 구조를 레이돔 구조를 제외하고 PEC 모델로 간략화 하였다. 시뮬레이션은 무인항공기의 날개와 Ventral Fin 위치에서 수행되어 졌고, 안테나 형상은 모노폴, 다이폴, 굴곡형 모노폴 안테나들을 이용하였다. 모노폴 안테나가 비행체 날개에 장착될 경우, 오른쪽 날개와 왼쪽 날개에 각각 장착되어지기 위하여 두 개의 안테나가 필요하고, 이 두 개의 안테나들은 가시선 데이터링크 지상 안테나에 대한 무인항공기 날개 방향에 따라 전환되어져야 한다. 모노폴 안테나가 Ventral Fin에 장착될 경우, 가시선 데이터링크 지상 안테나에 대한 무인항공기 날개 방향에 상관없이 하나의 안테나로 운용 가능하다. 또한, 안테나 이득도 비행체에 의한 Blockage 감소로 개선되어진다. 안테나 이득은 굴곡형 모노폴 안테나를 이용하여 더욱 더 개선되어 진다. 결론적으로 무인항공기에 장착된 UHF 안테나의 최적 위치 및 형상은 굴곡형 모노폴 안테나를 Ventral Fin 아래에 장착하는 것이다.

• 한국산학기술학회논문지
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• 제20권3호
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• pp.291-297
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• 2019

세계 주요 선진국들은 4차 산업혁명의 흐름에 따라 국가연구개발 투자의 지속적인 확대와 성과 창출을 통해 국가과학기술 역량을 향상시키고 있다. 기술 융 복합화에 따른 급속한 기술발달로 인해 새로운 패러다임에 대한 선제적 대응이 필요하게 되면서, 국가 경쟁력에 영향을 미치는 첨단 과학기술의 확보의 중요성은 나날이 커지고 있다. 기존 주력산업의 고도화 및 신 산업의 성장 동력화 추진과 국가 경쟁력을 좌우할 핵심기술과 미래 신기술은 국가 혁신역량 고도화를 위한 하나의 척도라 할 수 있다. 특히, 안보환경 변화와 향후 미래전장에 대비하기 위한 핵심기술과 미래 신기술은 무기체계를 개발하는 국방 분야에서 매우 중요하다. 국방 분야에서는 군 소요 무기체계에 근거한 핵심기술들을 식별 도출해내고 있으며, 소요에 기반하지 않고 민간의 우수기술을 국방에 활용하는 창의 도전적인 미래 신기술 발굴에 힘을 쏟고 있다. 본 연구에서는 국방 지상무인체계의 핵심기술과 미래 신기술에 대한 특성을 알아보고 실증적인 분석을 통해 비교연구를 진행하여, 핵심기술과 미래 신기술 특성에 따른 전략적 기술기획과 연구개발이 필요하다는 결론을 도출하였다.