• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2003년도 ISIS 2003
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• pp.240-243
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• 2003

In this study, as the preliminary step far developing a multi-purpose Autonomous robust carrier mobile robot to transport trolleys or heavy goods and serve as robotic nursing assistant in hospital wards. The aim of this paper is to present the use of multi-sensor data fusion such as sonar, IR sensor for map-building mobile robot to navigate, and presents an experimental mobile robot designed to operate autonomously within both indoor and outdoor environments. Smart sensory systems are crucial for successful autonomous systems. We will give an explanation for the robot system architecture designed and implemented in this study and a short review of existing techniques, since there exist several recent thorough books and review paper on this paper. It is first dealt with the general principle of the navigation and guidance architecture, then the detailed functions recognizing environments updated, obstacle detection and motion assessment, with the first results from the simulations run.

• 대한기계학회논문집
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• 제18권11호
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• pp.2902-2912
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• 1994

The ultrasonic array sensor system, consisting of one transmitter and fourreceivers instead of the traditional combination of a transmitter and a receiver is proposed in order to identify the location of objects. From the theoretical analysis and the experimental results, it is found that this new array sensor system could derive the information on the position of objects accurately, while the traditional sensor system could provide only the informatioin on the distance to objects. This sensor system is used to develop a sonar-based local mapping algorithm. The local map is used to find the existence of possible gates, through which the mobile robots can pass, and to select the suitable one in order for the robots to reach the goal safely in the presence of obstacles. The performance of the proposed local map algorithm is demonstrated experimentally in a small working area with several obstacles. It is found that the quality of the resulting local map is sufficient for the avoidance of collisions between the robots and obstacles and for the selection of the suitable gate leading to the goal. It is also shown that the global map of the working area could be obtained by integrating several local maps constructed from different locations and that it matches the actual layout of the working area well.

• 한국음향학회지
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• 제39권3호
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• pp.191-199
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• 2020

현재 압축센싱 기반 도래각 추정 알고리듬의 연구는 활발히 진행 중이나 비균일 센서 배열 기반 공분산 fitting 알고리듬의 성능에 대한 연구는 진행되지 않았다. 본 논문에서는 주파수 영역으로 확장된 압축센싱 기반 공분산 fitting 알고리듬의 유도과정을 다루며 센서배열이 비균일하게 배치된 경우와 센서배열의 일부 소자에 고장이 발생한 경우에 대한 해당 알고리듬의 도래각 추정 성능을 비교하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.923-924
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• 2006

In this paper, we propose the sensor fusing method for the obstacle avoidance of guiding robot for the visually impaired In our system, we acquire obstacles distances information using ultrasonic sensors, and its width is acquired by image sensor. We also compute avoidance angle using are distance and width information gained by sensor. After the robot avoid the obstacle by computed angle, the robot returns to its original path using odometry. The robot consists of the SA1110-based controller, sensory part using sonar array and image sensor, and motion part using differential drive for climbing stairs. This system use the embedded linux for OS, and also is developed by the QT/Embedded for GUI.

• 한국군사과학기술학회지
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• 제17권4호
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• pp.422-429
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• 2014

Proximity sensor networks are aimed at estimation kinematic state of target using estimated position of the target by each sensor node or target parameter. To analyze the kinematic state of target, traditional approaches require detections on multiple sensors, very large number of sensors to achieve acceptable performance. In this paper, we propose a novel method which can estimate predicted position of the underwater target using minimum proximity sensor with bearing information to this problem. The proposed algorithm was verified performance through simulation.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제7권3호
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• pp.198-204
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• 2007

In mobile robotics, ultrasonic sensors became standard devices for collision avoiding. Moreover, their applicability for map building and navigation has exploited in recent years. In this paper, as the preliminary step for developing a multi-purpose autonomous carrier mobile robot to transport trolleys or heavy goods and serve as robotic nursing assistant in hospital wards. The aim of this paper is to present the use of multi-sensor data fusion such as ultrasonic sensor, IR sensor for mobile robot to navigate, and presents an experimental mobile robot designed to operate autonomously within both indoor and outdoor environments. The global map building based on multi-sensor data fusion is applied for recognition an obstacle free path from a starting position to a known goal region, and simultaneously build a map of straight line segment geometric primitives based on the application of the Hough transform from the actual and noisy sonar data. We will give an explanation for the robot system architecture designed and implemented in this study and a short review of existing techniques, Hough transform, since there exist several recent thorough books and review paper on this paper. Experimental results with a real Pioneer DX2 mobile robot will demonstrate the effectiveness of the discussed methods.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.1408-1412
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• 2004

This paper presents a method that a mobile robot finds location of doors in complex environments and safely traverses the door. A robot must be able to find the door in order that it achieves the behavior that is scheduled after traversing a door. PCA(Principal Component Analysis) algorithm using the vision sensor is used for a robot to find the location of door. Fuzzy controller using sonar data is used for a robot to avoid an obstacle and traverse the doors.

• 한국음향학회지
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• 제34권3호
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• pp.200-209
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• 2015

수중 음향 감시 체계는 하이드로폰 배열을 이용하여 적함을 실시간으로 탐지하고 그 위치를 추적하는데, 해저 고정형 센서 배열은 이러한 감시 체계에 있어 중추적 역할을 수행한다. 본 연구에서는 천해 환경을 고려한 해저 고정형 원통형 하이드로폰 배열의 개념 설계를 유한요소해석을 통하여 수행하였다. 해양 배경 소음 하에서의 수신 특성 안정화를 위하여 금속 차단막을 이용한 배경 소음 스펙트럼 준위의 백색화 기법을 제안하였고, 배열 형상 최적화를 통하여 고각 및 방위각 방향의 지향성을 확보하였다. 나아가 소나돔의 형상과 재질에 따른 구조 진동 및 음향 산란 특성을 고찰하였다. 배경 소음 준위의 백색화, 배열 형상 최적화 및 소나돔의 음향적 투명화를 통하여, 해당 주파수 범위에 걸쳐 4 dB 이내의 감도 편차를 갖는 강건한 수신 특성의 하이드로폰 배열을 도출할 수 있음을 보였다.

• 한국음향학회지
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• 제26권4호
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• pp.166-172
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• 2007

본 논문에서는 표적 위치추정기법 및 관측잡음에 따른 다중상태 소나의 표적위치 추정성능에 대하여 논한다. 다중상태 소나망에 대한 기존 정보융합방법인 거리정보만을 이용하는 Maximum Likelihood (ML)와 거리정보와 방위정보를 함께 이용하는 Least Square (LS)에 대한 분석을 기반으로 거리정보와 방위정보를 함께 이용하는 ML을 제안한다. 각 센서가 거리정보와 방위정보를 이용한다고 가정할 때 다양한 잡음 환경하에 기존 방법과 제안된 방법에 대한 비교 실험을 수행했다. 또한 센서 수와 송신기, 수신기간 거리에 따른 표적위치 추정성능에 대한 연구를 수행했다. 실험결과에 의하여 제안된 거리정보와 방위정보를 함께 이용하는 ML의 제곱근 오차 성능이 송수신기간 거리가 길수록, 수신기 수가 적을수록 기존의 거리정보만 이용하는 ML, LS보다 더 우수한 것으로 나타났다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 하계종합학술대회논문집
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• pp.271-274
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• 1998

Ultrasonic sensors are becoming indispensable components in every sector of automation equipments due to many advantages. But the main purposes of the noncontact sensing device are rather narrowly confined within object detection and distance measurement. To widen the realm of the applications to object recognition, ultrasonic sensors need to improve the recognition resolution to a certain amount. To resolve the problem of spatial resolution restriction, an increased number of the sensors in the forms of a linear array or 2-dimensional array of the sensor has been used. Also better resolution has been obtained by shifting the array in several steps using mechanical actuators. For an object recognition using ultrasonic sensors, measurements of distance, shift, oblique angle in certain ranges should be obtained. But a little attention has been paid to the measurement of angles. In this paper we propose a practical method for an object angular value detection in addition to distance measurement in ultrasonic sensor array system with little additional hardware burden. Using the established measurement look-up table for the variations of distance, shift, angle and transmitter voltages for each sensor characteristics, a set of different return echo signals for adjacent receivers are processed to provide enhanced angular value reading for an object.