• Journal of Positioning, Navigation, and Timing
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• v.5 no.3
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• pp.145-156
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• 2016

A variety of methods for indoor positioning systems have been underway to ensure the safety of emergency rescuers who are working in dangerous situations such as fire fighters. However, since most systems display locations of rescue workers in two-dimension (2D)-based maps, it is difficult for a commander located in the outside to recognize locations of rescuers inside the building intuitively. An augmented reality (AR)-based indoor positioning monitoring system can display locations of rescuer inside the building that can be seen by commanders to help intuitive recognition of positioning. To monitor AR-based indoor positioning, it is necessary to have an estimation technique of line of sight vector of observers. In the present study, an estimation technique of a line of sight vector using ultra-wide band tranceiver installed inside the indoor to trace locations is presented.

• Journal of Positioning, Navigation, and Timing
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• v.12 no.3
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• pp.323-332
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• 2023

Today, services using Positioning, Navigation, and Timing (PNT) technology are provided in various fields, such as smartphone Location-Based Service (LBS) and autonomous driving. Generally, outdoor positioning techniques depend on the Global Navigation Satellite System (GNSS), and the need for positioning techniques that guarantee positioning accuracy, availability, and continuity is emerging with advances in service. In particular, continuity is not guaranteed in urban canyons where it is challenging to secure visible satellites with standalone GNSS, and even if more than four satellites are visible, the positioning accuracy and stability are reduced due to multipath channels. Research using Low Earth Orbit (LEO) satellites is already underway to overcome these limitations. In this study, we conducted a trend analysis of LEO-PNT research, an LEO satellite-based navigation and augmentation system. Through comparison with GNSS, the differentiation of LEO-PNT was confirmed, and the system design and receiver processing were analyzed according to LEO-PNT classification. Lastly, the current status of LEO-PNT development by country and institution was confirmed.

• Journal of Advanced Navigation Technology
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• v.9 no.2
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• pp.156-163
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• 2005

In this paper, we analyzed the performance of VDL mode 3 system model whose specification is defined by ICAO(International Civil Aviation Organization). For performance evaluation, we obtained BER(Bit Error Rate), transmission delay time, burst retransmission rate and throughput. From the analysis result, we could explicitly define relationships among BER, transmission delay time, throughput and burst restransmission rate. In addition, it became known that V/D retransmission rate and throughput are closely related in down link channel.

• Aerospace Engineering and Technology
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• v.12 no.1
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• pp.128-136
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• 2013

Recently, the localization recognition system research has been studied using various sensors according to increased interest in autonomous navigation flight. In case of indoor environment which cannot support GPS information, we have to look for another way to recognize current position. The Image-based localization recognition system has been interested although there are lots of way to know current pose. In this paper, we explain the localization recognition system based on mark and implementation of autonomous navigation flight. In order to apply to real environment which cannot support marks, localization based on real-time 3D map building is discussed.

• The Journal of the Korea Contents Association
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• v.14 no.4
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• pp.418-424
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• 2014

This paper aim; to develop the National R&D Information Navigation System(NRnDINS) that is convenient and easy to use by the researchers on the basis of information filtering and visualization by converging and integrating the three types of the contents, namely, paper, report and project at the stage of development of the information system An information system is developed by establishing ontology and RDF on the three types of contents, and by applying information filtering and semantic search technology after having created the prototype for the screen by reflecting the user needs analysis and information visualization elements surveyed at the previous stage of information service planning. In this paper, to make the measure for information filtering, R&D navigation index is prosed and implemented, and NRnDINS capable of integrated search of the R&D contents through information visualization is developed. Also, for the testing of the developed system, the preference survey for its design by 1m persons and usability test of the system by 10 users are performed The result of the survey on the preference for the design is affirmative with 85% of the subjects finding it favorable and the composite receptivity is good with the score of 87.2 the results of the usability test. However, it was also found that further development of the personalization functions is needed. It is hoped that the R&D navigation index of the proposed and implemented in this paper would present quantitative objectivity and will induce further development of other information filtering index of contents in the future.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.4
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• pp.114-130
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• 2022

The purpose of this study was to investigate the possibility of increasing the efficiency of disaster relief rescue operations through collaboration among multiple aerial and ground robots. The robots create 2.5D maps, which are merged into a 2.5D map. The 2.5D map can be handled by a low-specification controller of an aerial robot and is suitable for ground robot navigation. For localization of the aerial robot, a six-degree-of-freedom pose recognition method using VIO was applied. To build a 2.5D map, an image conversion technique was employed. In addition, to merge 2.5D maps, an image similarity calculation technique based on the features on a wall was used. Localization and navigation were performed using a ground robot to evaluate the reliability of the 2.5D map. As a result, it was possible to estimate the location with an average and standard error of less than 0.3 m for the place where the 2.5D map was normally built, and there were only four collisions for the obstacle with the smallest volume. Based on the 2.5D map building and map merging system for the aerial robot used in this study, it is expected that disaster response work efficiency can be improved by combining the advantages of heterogeneous robots.

• Journal of Navigation and Port Research
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• v.35 no.3
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• pp.187-195
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• 2011

A ship handling simulator is popular means of preventing marine accidents caused by human error. It can also be used to train navigators. A real-time 3D visualization system, a component of a ship handling simulator, is an important component, as realistic and intuitive image generation play an essential role in improving the effects of education using ship handling simulators. This paper discusses the design of a new real-time 3D visualization system based on an open source 3D graphics engine as well as its implementation. The developed real-time 3D visualization system satisfies the operational requirements derived in terms of visualization functionalities, reuse of legacy graphic data, and interoperability with other systems constituting a ship handling simulator. This system has an architecture in which new functionalities are easily added.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.11a
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• pp.617-620
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• 2003

3D 가상환경 개발 초기 단계에서부터 효과적인 Navigation을 위해서 Navigation Aid에 대한 연구가 꾸준히 진행되어왔으나 환경 구조의 중요 지점만을 정리한 요약 형태의 정보를 제공하는 방법이 주를 이루고 있어서, Navigation 대상 환경에 익숙지 않은 사용자에게 환경구조를 이해하게 하는 인지적 부담을 주고 있다. 본 논문에서는 사용자의 navigation을 위한 인지적 부담을 최소화할 수 있도록 토픽맵을 적용하여 투어코스를 자동생성 하는 시스템을 제안한다. 본 Navigation Aid 시스템은 가상환경 구조를 기억하거나 시스템 조작을 위한 일상적인 문제점에서 벗어나 본래의 목적에 집중할 수 있을 것이다. 가상환경에서의 Navigation 경험을 통해 현실세계에 존재하는 환경을 사전방문 하거나 효과적인 투어코스를 선정하는데 도움을 줄 수 있을 것으로 기대된다.

• The Journal of Korea Robotics Society
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• v.11 no.4
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• pp.226-234
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• 2016

In this study, a model-referenced underwater navigation algorithm is proposed for high-precise underwater navigation using monocular vision near underwater structures. The main idea of this navigation algorithm is that a 3D model-based pose estimation is combined with the inertial navigation using an extended Kalman filter (EKF). The spatial information obtained from the navigation algorithm is utilized for enabling the underwater robot to navigate near underwater structures whose geometric models are known a priori. For investigating the performance of the proposed approach the model-referenced navigation algorithm was applied to an underwater robot and a set of experiments was carried out in a water tank.