• 제목/요약/키워드: Omni Directional

검색결과 355건 처리시간 0.038초

합성개구레이더용 전방향 반사기의 설계 (Design of Omni-directional Reflector for Synthetic Aperture Radar)

  • 장지성;오이석;양찬수
    • 대한원격탐사학회지
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    • 제23권6호
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    • pp.501-506
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    • 2007
  • 본 연구에서는 합성개구레이더(synthetic aperture radar, SAR) 영상의 보정에 사용되고 있는 반사기(corner reflector, CR)를 이용하여 목표물의 식별과 인식을 위한 기초적인 연구를 실시하였다. 사각형 삼면 전파반사기를 기반으로 전방향(omni-directional) 반사기를 제작하였다. 여기서는 한 변의 길이가 15cm인 4-배열 사각형 삼면 전파반사기를 사용하여 C-밴드(주파수: 5.3 GHz) 의 편파별(VV, HH, VH, HV) RCS(radar cross section)특성을 해석하였다. 전파반사기는 대칭형이므로 방위각 180도 범위에 대해서 레이더 산란단면적 패턴을 측정하였다. VV편파의 경우, 방위각에 따른 RCS값의 차이가 8dB정도로 다른 편파보다 전방향 특성이 더 좋은 것으로 확인되었고, 방위각이 $0^{\circ}$ (단면과 동일 방향)와 $45^{\circ}$ (이웃하는 단면들의 중앙) 일 때, 가장 높은 RCS값을 보였다. 또한, 실험에서 얻어진 RCS값을 수치 해석 시뮬레이션과 이론적 계산과 비교를 실시한 결과, 서로 잘 일치하는 것으로 나왔다.

Omni-directional Gait Control of Quadruped Walking Robot

  • Son, Tae-Young;Kang, Tae-Hun;Kim, Hyung-Seok;Choi, Hyouk-Ryeol
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.2529-2534
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    • 2003
  • A quadruped walking robot has a superior adaptablility as well as highly adaptable mobility in various environments. These special advantages are outstanding in the mobile robot group. In this work, we introduce the method for omni-directional gait and rotational gait which is the generalized control algorithm to perform any direction commands. In addition, to improve the stability of quadruped walking robot, we performed the optimization between walking angle and sequence of feet. The proposed ideas are applied to the actual design of MRWALLSPECT III(Multifunctional Robot for Wall inSpection version 3) that is designed to inspect of the large surface of industrial utilities. By implementing the proposed idea on the robot, it’s effectiveness is experimentally confirmed.

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이동 로봇의 자율주행을 위한 전방향 능동거리 센서 (Active omni-directional range sensor for mobile robot navigation)

  • 정인수;조형석
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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    • pp.824-827
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    • 1996
  • Most autonomous mobile robots view things only in front of them. As a result, they may collide against objects moving from the side or behind. To overcome the problem we have built an Active Omni-directional Range Sensor that can obtain omnidirectional depth data by a laser conic plane and a conic mirror. In the navigation of the mobile robot, the proposed sensor system makes a laser conic plane by rotating the laser point source at high speed and achieves two dimensional depth map, in real time, once an image capture. The experimental results show that the proposed sensor system provides the best potential for navigation of the mobile robot in uncertain environment.

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Autonomous Omni-Directional Cleaning Robot System Design

  • Choi, Jun-Yong;Ock, Seung-Ho;Kim, San;Kim, Dong-Hwan
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.2019-2023
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    • 2005
  • In this paper, an autonomous omni directional cleaning robot which recognizes an obstacle and a battery charger is introduced. It utilizes a robot vision, ultra sonic sensors, and infrared sensors information along with appropriate algorithm. Three omni-directional wheels make the robot move any direction, enabling a faster maneuvering than a simple track typed robot. The robot system transfers command and image data through Blue-tooth wireless modules to be operated in a remote place. The robot vision associated with sensor data makes the robot proceed in an autonomous behavior. An autonomous battery charger searching is implemented by using a map-building which results in overcoming the error due to the slip on the wheels, and camera and sensor information.

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The Design and Actuator Sizing for Redundantly Actuated Omni-Directional Mobile Robot

  • Park, Tae-Bum;Yi, Jae-Hoon;Yi, Byung-Ju;Kim, Whea-Kuk;Yu, Bum-Jae;Oh, Sang-Rok
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.137.4-137
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    • 2001
  • Omni-directional mobile robots have been employed popularly in several application areas. However, the optimal design has not been considered yet. This paper introduces an optimal design methodology for omni-directional mobile robots. Optimal design parameters such as the offset distance and the wheel radius are identified with respect to isotropy. Furthermore, the force transmission ratio and actuator sizing problem are treated. Conclusivel, three cases are compared minimum actuation, two active caster wheel, and three active caster wheel, we claim that the redundantly actuated mobile robot with three active caster wheel has the best performance.

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전방향 소형비행로봇의 개발 (Development of A Omni-directional Flying Robot)

  • 이호길;원대희;박윤수;양광웅
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.302-305
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    • 2003
  • In this paper, dynamic behaviors of a small-sized flying robot with 4 rotors propelled by DC motor are discussed, and a control scheme based on the dynamic model to make stable flying motions, i.e., hovering, take-off, cruising behavior, etc. is proposed. The experimental results via some flying tests show good performances for practical use. The flying robot with 6DOF is controlled only 4 DOF, and the rest of two DOF are remained under the dynamic constraints. How to give the stability of all positions and orientations and to make the omni-directional motions in spite of such restrictions is analyzed. The proposed control scheme composes of two stages. First, PD control inputs for the trust-force and orientation are calculated, next the control inputs are distributed to each rotor by using a sort of Jacobian matrix. To design and control of a low cost - small sized flying robot, vibrated gyro sensor, cheap accelerometer, IR, and ultra sonic sensors are selected.

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동적 환경에서의 전방위 이동 로봇을 위한 서클 리스트(Circle List) 기반의 장애물 회피 (Circle List-Based Obstacle Avoidance for Omni-directional Mobile Robots in Dynamic Environments)

  • 천홍석;김병국
    • 제어로봇시스템학회논문지
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    • 제17권12호
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    • pp.1227-1233
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    • 2011
  • An effective method of obstacle avoidance for omni-directional mobile robots is proposed to avoid moving obstacles in dynamic environments. Our method uses the concept of circle lists which represent the trajectories of robot and obstacles. This method predicts not only collision position but also collision time, and hence it enables the robot avoiding the most urgent collision first. In order to avoid obstacles, our method uses artificial repulsive force and contraction force. Simulation results show that the robot could avoid obstacles effectively.

효과적인 강자성체 평판구조물 검사를 위한 전 방향 전단파 자기변형 패치 트랜스듀서 개발 (Development of an omni-directional shear-horizontal wave magnetostrictive patch transducer for the effective inspection of a ferromagnetic plate)

  • 승홍민;김윤영
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2014년도 추계학술대회 논문집
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    • pp.548-549
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    • 2014
  • Omni-directional shear-horizontal magnetostrictive patch transducers have a disadvantage that magnetic flux leakage into the plate when it is installed on a ferromagnetic plate. The leakage produces poor transduction efficiency and unwanted wave mode excitation which should be avoided in guided wave inspections of large plate-like structures. In order to resolve these problems, we newly developed a method to reduce the leakage into the plate. In the method, the patch and the magnet are vertically lifted off and their optimal positions are determined by numerical simulations. Also, the verification of the developed method is successfully verified by experiments.

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능동 분할 오프셋 캐스터 기반 전방향 차량의 설계 및 제어 (Design and Control of the Active Split Offset Caster based Omni-directional Vehicle)

  • 김한결;;박종찬;권동수
    • 로봇학회논문지
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    • 제8권2호
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    • pp.75-81
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    • 2013
  • This research would investigate deeply the operation of an omni-directional mobile robot that is able to move with high acceleration. For the high acceleration performance, the vehicle utilizes the structure of Active Split Offset Casters (ASOCs). This paper is mainly focused on inverse kinematics of the structure, hardware design to secure durability and preserve the wheels' contact to the ground during high acceleration, and localization for the real time position control.

A Study on the Performance of a 5 kW Scale VAWT with Omni-Directional Guide Vanes

  • Ryu, In-Ho;Hoang, Anh Dung;Kim, Jun-Ho;Lee, Ki-Seon;Yang, Chang-Jo
    • 한국유체기계학회 논문집
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    • 제19권4호
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    • pp.43-47
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    • 2016
  • Vertical axis wind turbine, despite of its limit in power efficiency, the simplicity in structure and maintenance is a competitive factor that keeps this type of turbine in the game until nowadays. Continuous solutions have been given to handle its major weakness and the use of omni-directional guide vane is an considerable one. In this paper, a 5kkW scale Savonius-based wind turbine enhanced with such guide vane system was design and studied. Together with reasonable blade design, the wind turbine shows promising performance compared with basic design while maintaining its original advantages.