• 제목/요약/키워드: Unknown environment

검색결과 540건 처리시간 0.024초

Performance Evaluation of Multi-Hop Communication Based on a Mobile Multi-Robot System in a Subterranean Laneway

  • Liu, Qing-Ling;Oh, Duk-Hwan
    • Journal of Information Processing Systems
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    • 제8권3호
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    • pp.471-482
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    • 2012
  • For disaster exploration and surveillance application, this paper aims to present a novel application of a multi-robot agent based on WSN and to evaluate a multi-hop communication caused by the robotics correspondingly, which are used in the uncertain and unknown subterranean tunnel. A Primary-Scout Multi-Robot System (PS-MRS) was proposed. A chain topology in a subterranean environment was implemented using a trimmed ZigBee2006 protocol stack to build the multi-hop communication network. The ZigBee IC-CC2530 modular circuit was adapted by mounting it on the PS-MRS. A physical experiment based on the strategy of PS-MRS was used in this paper to evaluate the efficiency of multi-hop communication and to realize the delivery of data packets in an unknown and uncertain underground laboratory environment.

가변적인 통신지연시간을 갖는 원격 작업 환경을 위한 실시간 햅틱 렌더링 (Real-Time Haptic Rendering for Tele-operation with Varying Communication Time Delay)

  • 이경노;정성엽
    • 동력기계공학회지
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    • 제13권2호
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    • pp.71-82
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    • 2009
  • This paper presents a real-time haptic rendering method for a realistic force feedback in a remote environment with varying communication time-delay. The remote environment is assumed as a virtual environment based on a computer graphics, for example, on-line shopping mall, internet game and cyber-education. The properties of a virtual object such as stiffness and viscosity are assumed to be unknown because they are changed according to the contact position and/or a penetrated depth into the object. The DARMAX model based output estimator is proposed to trace the correct impedance of the virtual object in real-time. The output estimator is developed on the input-output relationship. It can trace the varying impedance in real-time by virtue of P-matrix resetting algorithm. And the estimator can trace the correct impedance by using a white noise that prevents the biased input-output information. Realistic output forces are generated in real-time, by using the inputs and the estimated impedance, even though the communication time delay and the impedance of the virtual object are unknown and changed. The generated forces trace the analytical forces computed from the virtual model of the remote environment. Performance is demonstrated by experiments with a 1-dof haptic device and a spring-damper-based virtual model.

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이동로봇의 자율주행을 위한 다중센서융합기반의 지도작성 및 위치추정 (Map-Building and Position Estimation based on Multi-Sensor Fusion for Mobile Robot Navigation in an Unknown Environment)

  • 진태석;이민중;이장명
    • 제어로봇시스템학회논문지
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    • 제13권5호
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    • pp.434-443
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    • 2007
  • Presently, the exploration of an unknown environment is an important task for thee new generation of mobile service robots and mobile robots are navigated by means of a number of methods, using navigating systems such as the sonar-sensing system or the visual-sensing system. To fully utilize the strengths of both the sonar and visual sensing systems. This paper presents a technique for localization of a mobile robot using fusion data of multi-ultrasonic sensors and vision system. The mobile robot is designed for operating in a well-structured environment that can be represented by planes, edges, comers and cylinders in the view of structural features. In the case of ultrasonic sensors, these features have the range information in the form of the arc of a circle that is generally named as RCD(Region of Constant Depth). Localization is the continual provision of a knowledge of position which is deduced from it's a priori position estimation. The environment of a robot is modeled into a two dimensional grid map. we defines a vision-based environment recognition, phisically-based sonar sensor model and employs an extended Kalman filter to estimate position of the robot. The performance and simplicity of the approach is demonstrated with the results produced by sets of experiments using a mobile robot.

퍼지-뉴럴 네트워크를 이용한 자율 이동로봇의 운항 (Navigation of Autonomous Mobile Robot using Fuzzy Neural Network)

  • 최정원
    • 조명전기설비학회논문지
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    • 제22권4호
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    • pp.19-25
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    • 2008
  • 본 논문은 장애물에 대한 사전 정보를 가지고 있지 않은 미지의 공간에서 장애물의 회피와 지정된 목표점으로 이동할 수 있는 자율이동로봇을 위한 퍼지-뉴럴 네트워크를 이용한 지능제어 알고리즘을 제안하고, 제안된 제어기의 효용성을 모의실험과 실제 로봇의 구동실험을 통하여 검증을 한다. 제시한 지능제어기는 계층구조의 알고리즘으로 로봇이 목표에 도달하기 위한 퍼지 알고리즘과 주행 중 만날 수 있는 장애물들에 대한 회피를 수행하는 퍼지-뉴럴 알고리즘으로 구성된 계층과, 로봇이 이동하면서 만날 수 있는 여러 가지 상황에 따라 장애물 회피동작과 목표점 도달동작을 수행할 수 있도록 두 알고리즘에 적당한 가중치를 부여하는 가중치 퍼지 알고리즘으로 구성되어 있다. 그리고 로봇의 현재 운동정보와 장애물까지의 거리정보를 바탕으로 가중치 퍼지 알고리즘의 출력부 소속도 함수를 조절함으로서 오목한 장애물에 대해서도 장애물 회피 동작을 수행하도록 하였다. 제작된 로봇으로 제시한 알고리즘의 실효성을 검증하였다.

유전 프로그래밍을 이용한 미지의 환경에서 상호 협력하는 로봇 제어기의 설계 (Controller Design for Cooperative Robots in Unknown Environments using a Genetic Programming)

  • 정일권;이주장
    • 대한전기학회논문지:전력기술부문A
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    • 제48권9호
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    • pp.1154-1160
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    • 1999
  • A rule based controller is constructed for multiple robots accomplishing a given task in unknown environments by using genetic programming. The example task is playing a simplified soccer game, and the controller for robots that governs emergent cooperative behavior is successfully found using the proposed procedure A neural network controller constructed using the rule based controller is shown to be applicable in a more complex environment.

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미지 환경에서 이동로봇의 퍼지추론 기반 자율항법 (Autonomous Navigation of a Mobile Robot in Unknown Environment Based on Fuzzy Inference)

  • 조연;이동환;이홍규
    • 한국산학기술학회논문지
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    • 제17권3호
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    • pp.292-297
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    • 2016
  • 본 논문은 다양한 형태의 방해물에 대한 정보를 알 수 없는 미지의 환경에서 자율이동 로봇의 항법에 관한 제안을 하고 있다. 로봇의 이동에 따른 주변의 정보는 로봇에 부착되어 있는 근접센서를 통하여 감지하고, 충돌을 피하고 목적지에 가능한 한 빨리 도착할 수 있는 경로로 유도하기 위하여 퍼지추론에 기반 한 항해방법을 개발하였다. 여기에서 방해물들은 정지되어 있고 정형화된 경우와 비정형화된 형태들이 고려되었으며 미로와 U형태의 계곡으로 구성된 예리한 방해물들을 특별히 포함하고 있다. 벽을 따라 이동하는 방법 또한 제안하고 있으며 모의실험을 통하여 제안하고 있는 방법이 이동로봇의 항법문제를 해결하는 효과적인 방법이 된다는 것을 증명하였다.

스마트 스페이스에서 미지의 태그 위치 오차 보정 (Error Revision of the Unknown Tag Location in Smart Space)

  • 탁명환;지석근;주영훈
    • 제어로봇시스템학회논문지
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    • 제16권2호
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    • pp.158-163
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    • 2010
  • In this paper, we propose the location measurement algorithm of unknown tag based on RFID (Radio-Frequency IDentification) by using RSSI (Received Signal Strength Indication) and TDOA (Time Difference of Arrival) and extended Kalman filter in smart space. To do this, first, we recognize the location of unknown tag by using the RSSI and TDOA recognition methods. Second, we set the coordinate of the tag location measured by using trilateration and SX algorithm. But the tag location data measured by this method are included complex environmental error. So, we use the extended Kalman filter in order to revise error data of the tag location. Finally, we validate the applicability of the proposed method though the simulation in a complex environment.

자율이동로봇의 계층구조 제어 알고리즘의 개발 (Development of hierarchically structured control algorithm of a mobile robot)

  • 최정원;박찬규;이석규
    • 제어로봇시스템학회논문지
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    • 제9권5호
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    • pp.384-389
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    • 2003
  • We propose a hierarchically structured navigation algorithm for multiple mobile robots under unknown dynamic environment based on fussy-neural algorithm. The proposed algorithm consists of two basic layers. The lower layer consists of two parts such as fuzzy algorithm for goal approach and fuzzy-neural algorithm for obstacle avoidance. The upper layer which is basically fuzzy algorithm adjusts the magnitude of the weighting factor depending on the environmental situation. In addition, The proposed algorithm provides an efficient method to escape local mimimum points as shown in the simulation result. The efficacy of the proposed method is demonstrated via some simulations.

3D PASSAGE NAVIGATION UNDER UNKNOWN ENVIRONMENTS BASED ON DISTANCE FIELD SPACE MODEL

  • Nagata, Yoshitaka;Murai, Yasuyuki;Tsuji, Hiroyuki;Tokumasu, Shinji
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2003년도 ISIS 2003
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    • pp.500-503
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    • 2003
  • The navigation problem of robot is one of the main themes to deal with conficts or interferences between obstacles and the robot itself In this case, while the robot avoids obstacles on the space, the passage route should be determined efficiently. In order to solve problems above, we have come up with the distance field space medel (DFM) and then, under known environment, we have presented the distance field A algorithm for passage route path search. In this research, the method of performing the 3-dimensional passage route path search of robot under unknown environment is proposed. It is shown that the authors can build the distance search model the does not need space division by taking into account of sensor information to a distance field space model, and constructing this information as virtual obstacle information.

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The Application of RL and SVMs to Decide Action of Mobile Robot

  • Ko, Kwang-won;Oh, Yong-sul;Jung, Qeun-yong;Hoon Heo
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2003년도 ISIS 2003
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    • pp.496-499
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    • 2003
  • Support Vector Machines (SVMs) is applied to a practical problem as one of standard tools for machine learning. The application of Reinforcement Learning (RL) and SVMs in action of mobile robot is investigated. A technique to decide the action of autonomous mobile robot in practice is explained in the paper, The proposed method is to find n basis for good action of the system under unknown environment. In multi-dimensional sensor input, the most reasonable action can be automatically decided in each state by RL. Using SVMs, not only optimal decision policy but also generalized state in unknown environment is obtained.

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