• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.3105-3107
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• 1999

In this paper, we propose a new approach to autonomous wall-following of wheeled mobile robots using hybrid control system. The hybrid control approach IS introduced to the motion control of nonholonomic mobile robots in the Indoor navigation problems. In hybrid control architecture, the discrete states are defined by the user-defined constraints, and the reference motion commands are specified In the abstracted motions. The hybrid control system applied to motion planning and autonomous navigation with obstacle avoidance In indoor navigation problem. Simulation results show that it is an effective method for the autonomous navigation in indoor environments.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.3086-3088
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• 1999

An ultrasonic sensor is one of most popular sensor used to navigate mobile robots within environments containing obstacles. But many navigation algorithm have studied because of the drawback of ultrasonic sensor such that poor directionality, frequent misreadings, specular reflections. Also, the most crucial drawback of this algorithm, that is VFF, VFM, EDM, PFM, WFM, GFM etc. has been that the mobile robot may become trapped in a local minimum. In this paper, we present a theoretical study of a navigation algorithm which integrals a heuristic-search local minimum (or trap) recovery method with a vector-field based method to maneuver cylindric mobile robots in unknown of unstructured environments. Also, an autonomous mobile robot uses dead-reckoning to estimate the current position and orientation of a mobile robot.

• Proceedings of the KIEE Conference
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• 2003.07d
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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.

• Journal of the Korean Society of Industry Convergence
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• v.20 no.2
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• pp.89-95
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• 2017

In this paper, we suggest the method for a mobile robot to move safely from an initial position to a goal position in the wide environment like a building. There is a problem using odometry encoder sensor to estimate the position of a mobile robot in the wide environment like a building. Because of the phenomenon of wheel's slipping, a encoder sensor has the accumulated error of a sensor measurement as time. Therefore the error must be compensated with using other sensor. A vision sensor is used to compensate the position of a mobile robot as using the regularly attached light's panel on a building's ceiling. The method to create global path planning for a mobile robot model a building's map as a graph data type. Consequently, we can apply floyd's shortest path algorithm to find the path planning. The effectiveness of the method is verified through simulations and experiments.

• Proceedings of the Korea Information Processing Society Conference
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• 2018.05a
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• pp.250-252
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• 2018

본 논문은 4차 산업 혁명 핵심 기술인 자율주행에 대하여 기술하였으며 그 중 Hector Slam을 사용 하였다. Hector slam 같은 경우 RAM이 4G 이상 되어야 제대로 동작하지만 SBC(Odroid xu4) 같은 경우 RAM의 크기가 2G이므로 최적화할 필요성이 있다. SBC(Odroid xu4)에서도 사용 가능하도록 Hector slam 구현 최적화를 하였으며, 향후에 Aruco Marker를 이용하여 위치를 좀 더 섬세히 보정 해볼 것이며 또한 Aruco Marker의 ID를 통해 사물 인식을 하여 사람에게 사물에 대한 정보를 알려줌으로써 사람과 협업을 할 수 있는 로봇이 될 것이다.

• Proceedings of the Korea Information Processing Society Conference
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• 2012.04a
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• pp.843-845
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• 2012

전기자동차 또는 로봇의 자율 주행에 필요한 여러 가지 기술 가운데 위치 인식과 진행 방향을 결정하는 외부 환경인지 능력은 매우 중요하다. 본 논문에서는 GPS 수신 장치와 각종센서를 내장한 안드로이드 폰을 활용하여 자율 운행 중인 골프카트의 위치 정보를 획득하고 도로이탈 여부를 판별할 수 있는 시뮬레이션 시스템을 개발한다.

• IEMEK Journal of Embedded Systems and Applications
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• v.16 no.6
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• pp.293-297
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• 2021

This paper presents how to create a 3D map and solve problems related to generating a global path planning for navigation. Map creation and localization were performed using the RTAB-Map package to create a 3D map of the environment. In addition, when the target point is within the obstacle space, the problem of not generating a global path was solved using the asr_navfn package. The performance of the proposed system is validated through experiments with a wheelchair-type robot.

• IEMEK Journal of Embedded Systems and Applications
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• v.14 no.3
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• pp.151-156
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• 2019

According to recent advances in technology, major robot technologies that have been developed and commercialized for industrial use are being applied to various fields in our everyday life such as guide robots and cleaning robots. Among them, the navigation based on the self localization has become an essential element technology of the robot. In the case of indoor environment, many high-priced sensors are used, which makes it difficult to activate the robot industry. In this paper, we propose a robotic platform and a moving algorithm that can travel by using Dijkstra algorithm. The proposed system can find a short route to the destination with its own position. Also, its performance is discussed through the experimentation of an actual robot.

• Broadcasting and Media Magazine
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• v.26 no.2
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• pp.9-17
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• 2021

LiDAR는 조사된 빛이 피사체에 반사되어 돌아오는 시간을 측정하여 거리를 측정하는 장비로서, 넓은 영역과 긴 거리에 걸쳐 실세계의 정밀한 3차원 정보를 포인트 클라우드 데이터로 제공해 준다. 이러한 대용량 포인트 클라우드 데이터는 자율주행 자동차, 로봇, 3차원 지도 제작 등 컴퓨터 비전 기술을 이용하는 다양한 분야에 널리 활용될 수 있다. 그러나 유리 구조물을 포함하는 피사체를 LiDAR로 촬영하는 경우, 유리면에서 빛의 반사로 인한 가상의 포인트가 생성되어 실제 3차원 정보를 왜곡하는 문제가 있다. 포인트 클라우드의 후속 처리를 효율적으로 수행하기 위하여, 이러한 왜곡을 제거하는 전처리 기술이 필요하다. 본 고에서는 LiDAR의 취득 원리와 3차원 포인트 클라우드의 특성을 고찰하고, 유리 반사로 인한 왜곡된 가상의 포인트를 자동으로 검출하고 제거하는 새로운 연구 주제를 소개한다.

• IEMEK Journal of Embedded Systems and Applications
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• v.17 no.2
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• pp.109-114
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• 2022

This paper proposes a 2D joystick and LoRa-based teleoperation system for the Ackermman steering mobile robot. The proposed joystick mapping algorithm reduces the linear speed of the robot when the joystick is steered in the direction of the maximum steering angle in the high-speed driving state of a mobile robot to reduce the risk of rollover. The LoRa-based remote operation system is designed for remote operation of mobile robots that require long range communication with relatively little data transmission and low power. The proposed system is implemented and the experimental results demonstrate the effectiveness of the teleoperation system with respect to the stability of communication strength and the robot motion.