• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.9
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• pp.1718-1726
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• 2006

In this paper, we proposed a fuzzy controller and algorithm for efficiently obstacle avoidance in unknown space. The ultrasonic sensor is used for position and distance recognition of obstacle, and fuzzy controller is used for left and right wheels angular velocity control. The fuzzification is used singleton method and the control rule is each wheel forty-nine. The fuzzy inference is used simplified Mamdani's reasoning and defuzzification is used SCOG(Simplified Center Of Gravity). The computer simulation based on mobile robot modelling was performed for the capacity of fuzzy controller and the really applicable possibility revaluation of the proposed avoidance algorithm and fuzzy controller. As a result, mobile robot was exactly reached in target and it avoided obstacle efficiently.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.4
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• pp.19-25
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• 2008

This paper proposes a hierarchically structured navigation algorithm for autonomous mobile robot under unknown environment based on fuzzy-neal network. The proposed algorithm consists of two basic layers as follows. 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. The proposed algorithm provides an efficient method to escape local mimimum points as shown in the simulation result. Most simulation results show that this algorithm is very effective for autonomous mobile robots' traveling in unknown field.

• Journal of the Korean Institute of Intelligent Systems
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• v.13 no.2
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• pp.180-185
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• 2003

This paper proposes an intelligent navigation algorithm for multiple mobile robots under unknown dynamic environment. The proposed algorithm consists of three basic parts as follows. The first part based on the fuzzy rule generates the turning angle and moving distance of the robot for goal approach without obstacles. In the second part, using both fuzzy and neural network, the angle and distance of the robot to avoid collision with dynamic and static obstacles are obtained. The final adjustment of the weighting factor based on fuzzy rule for moving and avoiding distance of the robots is provided in the third stage. The experiments which demonstrate the performance of the proposed intelligent controller is described.

• Proceedings of the KIEE Conference
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• 2004.05a
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• pp.44-46
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• 2004

본 논문에서는 이동로봇이 임의의 선행물체를 추종할 때 진행 경로상에 이동장애물이 진입하는 경우 이 장애물을 효과적으로 회피할 수 있는 방법을 제시한다 초음파 센서를 이용하여 이동로봇의 진행경로에 진입하는 이동장애물에 대한 거리 정보와 방향각(Heading Angle)을 구할 수 있다. 이동로봇의 본체 주위에 배치된 16개의 초음파 센서를 이용하여 이동로봇의 전면, 후면 및 측면의 데이터를 얻을 수 있으며 이 정보를 퍼지제어기의 입력으로 사용한다 퍼지제어기는 이러한 입력정보와 제안된 규칙 베이스를 이용하여 이동로봇의 진행방향과 속도를 결정한다. 본 논문에서 제안한 퍼지제어기를 이용한 시뮬레이션을 통해 이동장애물에 대한 효과적인 충돌회피가 수행됨을 보인다.

• Journal of the Korean Institute of Intelligent Systems
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• v.22 no.1
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• pp.1-6
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• 2012

In this paper, we present an obstacle avoidance control algorithm for mobile robots based on SFLC (single-input fuzzy logic controller) with an efficient fuzzy logic look-up table to replace the traditional complicated operation. This method achieves better performance than traditional methods in terms of efficiency. The output of a SFLC leads the robot to the target automatically although many obstacles on the path. Our experiments show that the robot has good performance in the view of path tracking and other efficiency.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.4
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• pp.470-477
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• 2009

Modular reconfigurable robots with physical docking capability easily adapt to a new environment and many studies are necessary for the modular robots. In this paper, we propose a vision-based fuzzy autonomous docking controller for the modular docking robots. A modular docking robot platform which performs real-time image processing is designed and color-based object recognition method is implemented on the embedded system. The docking robot can navigate to a subgoal near a target robot while avoiding obstacles. Both a fuzzy obstacle avoidance controller and a fuzzy navigation controller for subgoal tracking are designed. We propose an autonomous docking controller using the fuzzy obstacle avoidance and navigation controllers, absolute distance information and direction informations of robots from PSD sensors and a compass sensor. We verify the proposed docking control method by docking experiments of the developed modular robots in the various environments with different distances and directions between robots.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2002.12a
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• pp.211-214
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• 2002

본 연구에서는 지체 부자유자들이 가장 많이 사용하는 전동형 휠체어를 이용하여, 조이스틱과 음성인식 모듈을 전동 휠체어에 부착하고 여기에 인공지능 기법을 적용하여 조이스틱과 음성인식 의해 휠체어를 제어하였으며, 각 휠체어의 각 부분을 모듈별로 구성하여 제작하였다. 그리고 조이스틱으로 휠체어를 제어하지 않고 음성인식으로 만 휠체어를 제어 동작했을 경우에 휠체어가 주행중에 장애물이 주행 경로 상에 갑자기 나타났을 때 장애물에 대해 즉시 정지하거나 회피하지 못할 경우가 발생하게 된다. 그래서 전동휠체어의 앞면과 됫면에 초음파 센서를 부착하여 갑자기 장애물이 나타났을 때 전동휠체어가 장애물에 대해 지능적으로 정지하거나 회피 할 수 있도록 퍼지이론을 적용하여 장애물에 대해서 지능적인 동작이 가능하도록 하였다.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.5
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• pp.635-640
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• 2009

In real system application, the obstacle avoidance system for the autonomous control of the underwater flight vehicle (UFV) operates with the following problems: it has local information because the sonar can only offer the obstacle information in a local detection area, it requires a continuous control input because the system that has reduced acoustic noise and power consumption is necessary, and further, it requires an easy design procedure in terms of its structures and parameters. To solve these problems, an intelligent obstacle avoidance algorithm using the evolution strategy (ES) and the fuzzy logic controller (FLC), is proposed. To verify the performance of the proposed algorithm, the obstacle avoidance of UFV is performed. Simulation results show that the proposed algorithm effectively solves the problems in the real system application.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09b
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• pp.9-12
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• 2003

본 논문에서는 미지의 환경에서 인터넷 기반에 대한 이동로봇의 자율 주행이 가능하도록 비젼시스템과 퍼지규칙을 이용한 경로 설정 및 장애물 회피를 위한 알고리즘을 소개 하고자 한다. 한편 원격지에서도 로봇의 움직임을 파악할 수 있도록 인터넷을 통한 원격운용 기능을 추가함으로써 로봇의 효율적인 제어가 가능하도록 하였다. 원격지에서 제어하고자 할 때 대부분이 인터넷이나 무선을 이용한 원격제어 또는 실시간 모니터링을 통해 제어하여 그 상황을 시뮬레이션으로 구현하고 있다. 현재 이동로봇 제어를 할 때 많이 사용되는 방법은 IEEE 802.11b를 기반으로 한 wireless LAN Socket, TCP/IP, RF, 블루투스 통신등이 있다. 이러한 방식중 본 논문에서는 Internet 방식 중에 TCP/IP 프로토콜을 사용하였다. 전체 시스템은 이동로봇과 서버 그리고 클라이언트로 구성되며 이동 로봇은 인터넷을 통해서 로봇을 제어하거나 필요에 따라서는 로봇이 직접 제어권을 가지고 자율주행이 가능하도록 설계되었다. 본 논문에서는 퍼지규칙을 이용하여 경로 계획 및 장애물 회피를 위한 알고리즘을 생성하였으며, 실험을 통한 그 효율성을 검증하였다. 또한 실제 이동 로봇을 제작하여 실험한 결과에서도 제안된 알고리즘이 우수한 성능을 발휘함을 확인할 수 있었다.

• Journal of the Korean Institute of Intelligent Systems
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• v.21 no.3
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• pp.323-328
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• 2011

In real system application, the 3-D obstacle avoidance system for the autonomous control of the underwater flight vehicle (UFV) operates with the following problems: the sonar offers the range/bearing information of obstacles in a local detection area, it requires the system that has reduced acoustic noise and power consumption in terms of the autonomous underwater vehicle (AUV), it has the UFV operation constraints such as maximum pitch and depth, and it requires an easy design procedure in terms of its structures and parameters. To solve these problems, an intelligent 3-D obstacle avoidance algorithm using the evolution strategy (ES) and the fuzzy logic controller (FLC), is proposed. To verify the performance of the proposed algorithm, the 3-D obstacle avoidance of UFV is performed. Simulation results show that the proposed algorithm effectively solves the problems in the real system application.