• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.6
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• pp.803-812
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• 2017

This paper proposes a local path planning method for stable autonomous driving in rough terrain. There are various path planning techniques such as candidate paths, star algorithm, and Rapidly-exploring Random Tree algorithms. However, such existing path planning has limitations to reflecting the stability of unmanned ground vehicles. This paper suggest a path planning algorithm that considering the stability of unmanned ground vehicles. The algorithm is based on the genetic algorithm and assumes to have probability based obstacle map and elevation map. The simulation result show that the proposed algorithm can be used for real-time local path planning in rough terrain.

• Proceedings of the Korean Society of Computer Information Conference
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• 2010.07a
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• pp.51-54
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• 2010

본 논문에서는 포텐셜 필드 방법과 퍼지로직 시스템을 이용하여 멀티 모바일 로봇의 충돌회피를 위한 경로계획을 연구한다. 잘 알려진 포텐셜 필드 방법은 멀티 모바일 로봇 시스템에 있어서 각각의 로봇에 대한 전역경로를 계획하기 위해 사용되었으며, 퍼지로직 시스템은 각 로봇에 근접하는 혹은 진행하는 로봇의 경로를 가로막는 장애물과의 충돌을 피하고 안전하게 목적지에 도달하기 위한 지역경로를 계획하기 위해 이용되었다.

• Spatial Information Research
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• v.9 no.1
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• pp.15-30
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• 2001

Solid waste collection service is viewed as one of the most important public services in urban area. The purpose of this study is to apply the GIS based regional partitioning and arc routing methods for solid waste collection districting and vehicle routing-scheduling in order to provide waste collection service more efficiently. In this study, solid waste deposit sites are derived from the centroid of each building and the amount of solid waste is deduced based on the number of households and establishments. The regional partitioning procedure is performed based on waste collection zones which are constructed from waste deposit sites. The result of this study shows that solid waste collection districts which are delineated by regional partitioning method are able to increase efficiencies and cut costs in performing solid waste collection services. Also the output of vehicle-scheduling from the analysis of arc routing may provide more efficiently and quickly manage the scheduling of the residential solid waste collection routes, reducing costs with minimal deadheading costs. Therefore, the application of GIS based on regional partitioning and arc routing methods would be very useful to construct a solid waste management system by supplying the important and flexible informations for solid waste collection districts and vehicle routing-scheduling for waste collection.

• Journal of the Korean Institute of Intelligent Systems
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• v.8 no.4
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• pp.27-35
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• 1998

Navigation is a method to direct a mobile robot without collision when traversing the environment. This is to reach a destination without getting lost. In this paper, global and local path planning in fixed obstacle and moving obstacle using genetic algorithm are presented. First, mobile robot searches optimal global path using genetic algorithm without falling into local minima. Then if it finds a unknown obstacle, it searches new path without crashing obstacle. Also if there is a moving obstacle, mobile robot searches new optimal path without colliding with the obstacles. Various simulation results show the proposed algorithm can search a shortest path effectively.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.8
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• pp.907-914
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• 2014

A heuristic search algorithm is proposed to plan a collision free path for robots in an indoor environment. The proposed algorithm is to find a collision free path in the gridded configuration space by proposed heuristic graph search algorithm. The proposed algorithm largely consists of two parts : tunnel searching and path searching in the tunnel. The tunnel searching algorithm finds a thicker path from start grid to goal grid in grid configuration space. The tunnel is constructed with large grid defined as a connected several minimum size grids in grid-based configuration space. The path searching algorithm then searches a path in the tunnel with minimum grids. The computational time of the proposed algorithm is less than the other graph search algorithm and we analysis the time complexity. To show the validity of the proposed algorithm, some numerical examples are illustrated for robot.

• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.2
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• pp.99-110
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• 2009

This study is to establish urban green network on the urbanized area using characteristics of fragmented and ornamental green area distribution. To do this, the survey for the green area characteristics was carried out in Changwon City. In order to analyze network, a virtual network in whole city sky for bird's movement, which is consisted with 30m grid lines was prepared. To analyze which network routes depend on the direction, we estimated bird's movement between 8-direction and 16-direction's outskirt forest's source point and inner city's fragmented green area. In the analysis of two types different direction models, the results of green network routes are mostly matched. So green network plan by this results is more reasonable for enhancing bird's movement to inner city. Based on the these findings, this green network planning will be providing for inner city to influx outside forest's birds and maximize the ecological connectivity.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.421-424
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• 1998

In this paper, a new on-line local path planning algorithm without local minima problem is proposed. This method, called Window Analysis Method (WAM), is simple and fast, and it helps a robot take a safe path avoiding obstacles in unknown environment. WAM has simulated on the mobile robot to demonstrate its reliability and fesibility.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2417-2419
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• 2003

이동성에 nonholonomic 제약을 받는 차륜 구동 이동 로봇의 불확실한 환경에서의 자율 주행 제어기를 제안하였다. 전체 시스템은 on-line으로 지역경로 계획을 하는 planner 부분과 차륜 구동 이동 로봇의 nonholonomic 제약을 극복하면서 계획된 지역 경로를 충실히 추종하기 위한 제어기 부분의 두 부분으로 구성하였다. Planner는 빠른 응답을 생성하고, 전역적인 정보를 사용하지 않기 위하여 반사적인 제어 방식에 의한 경로 생성 방식을 채택하였고, 제어기 부분은 비선형 posture feedback stabilizer로 설계하였다. 제안된 시스템은 단순한 형태의 제어 방식으로 완전한 자율적인 판단에 의한 장애물 회피와 목표 지점으로의 수렴 능력을 보여 준다. 본 시스템의 단순하면서도 효과적인 자율주행 능력은 반사제어 방식의 장점과 feedback 제어기의 증명된 안정성에서 기인한다. 시뮬레이션과 자체 구현한 차륜 구동 이동 로봇인 "MARI"로 실제 환경에서의 실험을 실시하여 제안된 제어기의 유효성을 검증하였다.

• International Journal of Highway Engineering
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• v.13 no.4
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• pp.1-8
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• 2011

The purpose of this study is to suggest the optimized transfer algorithm of earthwork considering the precluded area such as the lake, bogs. The earthwork transfer plan in massive cutting and banking should be established because of affecting the construction cost highly. Until now, there was the study about the optimized earthwork transfer model considering the OR(Operating Research). but isn't the study about the model considering the precluded area such as the lake, bogs. In most cases, the engineer adjusts the earthwork transfer path considering the precluded area, manually. The presented model suggests to calculate various visibility paths with $A^*$algorithm after converting the precluded area to polygon topology. By using this paths, the minimum cost path to optimize the earthwork transfer can be obtained. In this study, the validity of the model was proved as implementing the system for the optimized earthwork transfer considering the precluded area.

• Spatial Information Research
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• v.19 no.1
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• pp.1-11
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• 2011

Recently urban area has suffered from frequent flood event by local heavy rain. This study performed flood tests for the Jungnang river using HEC-RAS model. Based on 1m LiDAR data, river geometry data were produced using HEC-GeoRAS. For 100-year frequency flood, 200-year frequency flood, and PMF, flooding areas were estimated. Ten sub-zones of the entire flooding area were identified based on the nearest refugees and used to analyze evacuation paths to the refugees. The results showed that approximately 70% of flooded area were residential, commercial, and transportation areas so that much loss of life and property could be possible. Path analysis showed that the shortest path distances to refugees were about 1000m average. Evacuation warning given at a proper period could minimize loss of life and property. This study provides the guideline for flood evacuation plan in urban area.