• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 D
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• pp.2335-2337
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• 2001

In this paper, we address a new complete coverage navigation algorithm and guidance methodology for the cleaning robot. The proposed algorithm is based on the grid map. Six templates, excluding a Back-Trace(BT) template are used as the local navigation method. The effectiveness of the algorithm proposed in this paper is thoroughly demonstrated through simulations and the evaluation of parameters for the path execution.

• Journal of Mechanical Science and Technology
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• 제18권1호
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• pp.132-144
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• 2004

This paper presents a new method driving multiple robots to their goal position without collision. To consider the movement of the robots in a work area, we adopt the concept of avoidability measure. The avoidability measure figures the degree of how easily a robot can avoid other robots considering the velocity of the robots. To implement the concept to avoid collision among multiple robots, relative distance between the robots is proposed. The relative distance is a virtual distance between robots indicating the threat of collision between the robots. Based on the relative distance, the method calculates repulsive force against a robot from the other robots. Also, attractive force toward the goal position is calculated in terms of the relative distance. These repulsive force and attractive force are added to form the driving force for robot motion. The proposed method is simulated for several cases. The results show that the proposed method steers robots to open space anticipating the approach of other robots. In contrast, since the usual potential field method initiates avoidance motion later than the proposed method, it sometimes fails preventing collision or causes hasty motion to avoid other robots. The proposed method works as a local collision-free motion coordination method in conjunction with higher level of task planning and path planning method for multiple robots to do a collaborative job.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 D
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• pp.2588-2590
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• 2003

The part of manipulators is normally studied with regularized environmental conditions. however, it is the most difficult that the part of AMR must be studied with uncertainty in the environmental conditions. The part of AMR has skelton, sensor fusion, path planning etc. This paper is the research of the local pass planning that gathers information about external environment using neural network from each sensors and designs the algorithm which can determine which correct direction the robot can find. As the result of the research, AMR has been able to drive similarly as if the expert does and has been able to observe it acting without any control.

• 한국산학기술학회논문지
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• 제15권12호
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• pp.6986-6992
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• 2014

일반화된 보로노이 그래프(GVG)는 자율 주행 로봇을 위한 일종의 로드맵으로서. GVG는 선서에다 받은 정보만 사용하여 작업 공간거리의 계산에 따라 정의를 한다. 로봇은 장애물까지의 최대 거리를 검출할 수 있기 때문에 포인트 뷰에서 GVG의 최적은 정출 몇 장애물 회피이다. 로봇의 경우에는, GVG는 가장 안전적인 길이라고 할 수 있다. 따라서 높이 링크 로봇의 GVG가장거리에 대한 연구가 매우 필요하다. 기존 연구에서 점(point) 로봇을 위한 GVG(point-GVG)와 로드 로봇을 위한 GVG(rod-GVG)가 발표되었다. 이 논문은 더 고차원의 로봇인 두 개의 동일 링크가 관절로 연결된(tow-identical-link; L2) 로봇을 위한 GVG(L2-GVG)에 대한 연구이다. L2-GVG는 미지의 평면 작업공간에서 움직이는 L2 로봇의 짜임새 공간 $R^2{\times}T^2$상에서 로드맵을 생성하되, 이전 연구와 마찬가지로 지역적 센서 정보만을 이용해 로봇이 스스로 주행하면서 맵을 만들어 낸다. 이 논문에서는 이전 point-GVG와 rod-GVG에서는 나타나지 않는, 관절이 존재하여 생기는 복잡한 특성에 대해서 분석한다. 이는 다관절 로봇으로의 확장에 중요한 초석이 될 것이다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1589-1592
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• 1997

Among the prerequisite abilities (perception of environment, path planning and position estimation) of an autonomous mobile robot, position estimation has been seldom studied by mobile robot researchers. In most cases, conventional positioin estimation has been performed by placing landmarks or giving the entrire environmental information in advance. Unlikely to the conventional ones, the study addresses a new method that the robot itself can select distinctive features in the environment and save them as landmarks without any a priori knowledge, which can maximize the autonomous behavior of the robot. First, an orjentaion probaility model is applied to construct a lcoal map of robot's surrounding. The feature of the object in the map is then extracted and the map is saved as landmark. Also, presented is the position estimation method that utilizes the correspondence between landmarks and current local map. In dong this, the uncertainty of the robot's current positioin is estimated in order to select the corresponding landmark stored in the previous steps. The usefulness of all these approaches are illustrated with the results porduced by a real robot equipped with ultrasonic sensors.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.822-827
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• 2003

Topological maps have drawn more attention recently because they are compact, provide natural interfaces, and are applicable to path planning easily. To build a topological map incrementally, Voronoi diagram was used by many researchers. The Voronoi diagram, however, has difficulty in applying to arbitrarily shaped objects and needs long computation time. In this paper, we present a new method for global topological map from the local topological maps incrementally. The local topological maps are created through a thinning algorithm from a local grid map, which is built based on the sensor information at the current robot position. A thinning method requires simpler computation than the Voronoi diagram. Localization based on the topological map is usually difficult, but additional nodes created by the thinning method can improve localization performance. A series of experiments have been conducted using a two-wheeled mobile robot equipped with a laser scanner. It is shown that the proposed scheme can create satisfactory topological maps.

• KIEAE Journal
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• 제10권5호
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• pp.13-22
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• 2010

The old city centers of local metropolitans have lost their functions as CBD in korea. Those old city centers have an only role as a gate connected to the new CBD. This study aims to present regeneration stratigies of old city centers through Osaka case study. This research has been focused on the physical and environmental factors in urban regeneration. There are 4 strategies for old city centers. First, the strategy to attract people to the old city centers is high-density and mixed-use development having functions like shopping, entertainment, residence. This kind of development makes local metropolitan cities compact cities to protect urban sprawl. Second, strategy to give old city centers an identity is to conserve traditional culture and structures and to revitalize retail market. Third is to make pedestrian-friendly street system. Osaka ism't pedestrian friendly but remodelling the connect the pedestrian path to the culture facilities. Fourth is to have water and green environment. Green space is the strong factor that pull people to old city centers.

• Journal of Korea Trade
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• 제23권7호
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• pp.64-82
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• 2019

Purpose - This study's the ultimate goal is to analyze competitiveness improvement on multinational enterprises as firstly providing which factors are to strengthen or weaken competitiveness, secondly investigating if hypotheses development and research design is correct and thirdly finding significant implications for research and practices across country specific advantage. Design/methodology - Using feedback data provided by 250 firms, we extracted variable factors and hypotheses, which were empirically carried out by reliability and validity testing, correlation analysis, path analysis, and confirmatory factor analysis to prove which factors are to make the positive effect on the improvement of overseas subsidiaries' management performance and competitiveness. Findings - Through proceeding empirical analysis study, we found out that technology management capability, knowledge management capability, and local management capability had a statistically significant effect on the improvement of overseas subsidiaries' competitiveness, while linked activity capability revealed a negative effect. Originality/value - During business globalization, overseas investments and establishment of overseas subsidiaries have been essential. It is anticipated that this study results would be meaningful for analysis on multinational enterprises' competitiveness and helpful in promoting their entry into Korean market and enhancing their competitiveness. This paper would also help Korea government develops new FDI model and induce more investment from global major companies to Korea region.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.227-230
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• 1997

In this paper, robot navigation experiments with a new navigation algorithm are carried out in real environments. The authors already proposed a reactive navigation algorithm for mobile robots using optimal via-point selection method. At each sampling time, a number of via-point candidates is constructed with various candidates of heading angles and velocities. The robot detects surrounding obstacles, and the proposed algorithm utilizes fuzzy multi-attribute decision making in selecting the optimal via-point the robot would proceed at next step. Fuzzy decision making allows the robot to choose the most qualified via-point even when the two navigation goals-obstacle avoidance and target point reaching-conflict each other. The experimental result shows the successful navigation can be achieved with the proposed navigation algorithm for real environments.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2002년도 춘계학술대회 및 임시총회
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• pp.140-143
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• 2002

본 논문에서는 자율수중운동체(AUV, Autonomous Underwater Vehicle)의 실시간 충돌회피에 적용되는 휴리스틱 탐색기법에 적합한 퍼지조건연산자와 알파절단(aleph-cut)의 선택에 관해 논한다. 퍼지조건연산자와 알파절단은 두 퍼지관계에서 새로운 퍼지관계를 생성시키는 퍼지삼각논리곱의 연산에 적용되는데 이것은 휴리스틱탐색기법의 이론적 기반이 된다. 본 논문은 평가함수를 이용한 새로운 휴리스틱탐색기법을 설계하고, 이에 가장 적합한 퍼지조건연산자와 알파절단을 제안한다. 제안된 퍼지조건연산자와 알파절단의 검증을 위해 경로경비와 합리적인 경로를 생성하는 알파절단의 개수 관점에서 모든 경우의 퍼지조건연산자와 알파절단에 대해 시뮬레이션 한다. .