• 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.

• 융합보안논문지
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• 제19권2호
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• pp.73-81
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• 2019

본 논문은 시간 가중치 기반의 중간지점 탐색 알고리즘과 사용자 선호 기반 장소 추천 알고리즘을 이용한 사용자 중심의 중간지점 탐색 시스템을 제안한다. 제안된 시스템은 중간지점 탐색을 위하여 사용자간의 출발지점을 기준으로 각 사용자의 시간 가중치를 적용하여 중간 지점을 산출하는 중간지점 탐색 모듈과 각 사용자와 산출된 중간지점까지의 경로 탐색을 제공하기 위한 지점 탐색 제공 모듈로 구성된다. 또한, 중간지점 탐색 결과를 기반으로 사용자의 선호도 중심의 1장소 추천 기능을 포함하여 사용자의 이용률을 증대할 수 있도록 한다. 실험 결과, 제안된 시스템은 사용자 중심의 중간지점 및 장소 추천 기능을 통해 이용의 효율성을 증대시킬 수 있음을 확인하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.82-82
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• 2000

The way which estimates a position from Navigation is Dead-reckoning Navigation and Radio Navigation. Generally dead-reckoning navigation uses Gyro and odometer as sensor, but these have problems which are an integrating noise and a noise-sensitivity. Gps which is used by radio-navigation has a Troposthetic error and MultiPath ewer and so on. For minimizing a Troposthetic error and a Multipath error, this paper suggests to an algorithm which use vanishing point on CCD camera.

• 대한임베디드공학회논문지
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• 제8권4호
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• pp.205-212
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• 2013

In recent, the demand of Unmanned Aerial Vehicles (UAVs) that can autonomous navigation and remote control has been increased in military, civil and commercial field. Particularly, existing researches focused on autonomous navigation method based on vanish point and remote control method based on event processing in indoor environments. However, the existing methods have some problems. For instance, a detected vanish point in intersection point has too much detection errors. In addition, the delay is increased in existing remote control system for processing images in real time. Thus, we propose improved vanish point algorithm by removing detection errors in intersection point. We also develop a remote control system with android platform by separating flying control and image process. Finally, we compare the proposed methods with existing methods to show the improvement of our approaches.

• 전기학회논문지
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• 제63권1호
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• pp.108-114
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• 2014

This paper proposes a generation method of a navigation guidance direction and a fuzzy controller to achieve the autonomous navigation of a mobile robot using a particle swarm optimization(PSO) scheme in unknown environments. The proposed navigation guidance direction is the direction that leads a mobile robot to arrive a target point simultaneously with avoiding obstacles efficiently according to the surrounding local informations. It is generated by selecting the most suitable direction of the many directions in the surrounding environment using a particle swarm optimization scheme. Also, a robot can reach a target point with avoiding the various obstacles by controlling the robot so that it can move from its current orientation to the navigation guidance direction using the proposed fuzzy controller. Simulation results are presented to show the feasibility and validity of the proposed robot navigation scheme.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.1071-1076
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• 1990

This paper proposes a navigation strategy of multiple autonomous mobile robots with communication within a specified space. Assuming that each robot has complete detectability with finite range, simple navigation strategy is derived by introducing repulsive forces between robots and attractive force between a robot and its goal point analogous to those between electric charges. When a robot is close to its goal point, a pseudo-domain based on the distance between the closest point of the domain boundary and the goal point is proposed to enhance its convergence to the goal state. This paper concludes with the results of computer simulation studies on the dynamic behavior of multiple interacting robots with the proposed navigation strategy.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1450-1455
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• 2005

This paper describes a DR construction for land navigation and the sigma point based receding horizon Kalman FIR (SPRHKF) filter for DR/GPS hybrid navigation system. A simple DR construction is adopted to improve the performance both of the pure land DR navigation and the DR/GSP hybrid navigation system. In order to overcome the flaws of the EKF, the SPKF is merged with the receding horizon strategy. This filter has several advantages over the EKF, the SPKF, and the RHKF filter. The advantages include the robustness to the system model uncertainty, the initial estimation error, temporary unknown bias, and etc. The computational burden is reduced. Especially, the proposed filter works well even in the case of exiting the unmodeled random walk of the inertial sensors, which can be occurred in the MEMS inertial sensors by temperature variation. Therefore, the SPRHKF filter can provide the navigation information with good quality in the DR/GPS hybrid navigation system for land navigation seamlessly.

• 한국항행학회논문지
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• 제14권6호
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• pp.783-790
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• 2010

현재 대부분의 선박은 해상에서의 안전한 운항을 위하여 GPS를 이용하여 선박 위치를 파악하고 있다. 이 연구에서는 GPS 정밀단독측위기법을 이용하여 준실시간으로 해상 선박의 위치를 결정하고, 그 정밀도를 분석하였다. 이를 위하여 선박에 GPS 장비를 설치하여 남해안 관측을 실시하였다. 정밀단독측위 기법을 이용한 GPS 관측데이터 처리를 위하여 JPL에서 개발한 GIPSY-OASIS를 이용하였으며, 안테나 위상 중심 변동량과 해양 조석하중에 의한 지각 변동량, 그리고 방위각 방향으로의 대류층 지연량을 보정하였다. 그 결과 이 연구에서 산출한 준실시간 좌표는 ~1cm 수준의 정밀도를 달성하였다.

• Journal of Positioning, Navigation, and Timing
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• 제11권3호
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• pp.199-208
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• 2022

Inertial Navigation System (INS)/Global Navigation Satellite System (GNSS) integrated navigation system can be used for land vehicle navigation. When the GNSS signal is blocked in a dense urban area or tunnel, however, the problem of increasing the error over time is unavoidable because navigation must be performed only with the INS. In this paper, Non-Holonomic Constraints (NHC) information is utilized to solve this problem. The NHC may correct some of the errors of the INS. However, it should be noted that NHC information is not applicable to all areas within the vehicle. In other words, the lever arm effect occurs according to the distance between the Inertial Measurement Unit (IMU) mounting position and the NHC effective point, which causes the NHC condition not to be satisfied at the IMU mounting position. In this paper, an INS/GNSS/NHC integrated navigation filter is designed, and this filter has a function to compensate for the lever arm effect. Therefore, NHC information can be safely used regardless of the vehicle's driving environment. The performance of the proposed technology is verified through Monte-Carlo simulation, and the performance is confirmed through experimental test.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2012년도 추계학술대회
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• pp.160-161
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• 2012

The traditional theory regarding the pivot point of a ship during maneuvering, so called apparent pivot point, is located nearly at 1/3 ship's length from the bow when the ship is moving ahead, and between 1/4 ship's length from the stern and the rudder post when going astern. The pivot point is sometimes considered to be the centre of leverage for forces acting on the ship. However, the pivot point is located out of ship due to strong lateral force, such as current and it is very inconvenient to use during maneuvering a ship. In this paper firstly, pivot points due to ship's condition are investigated carefully. And then the center of lateral resistance used at the present are determined. While a new lateral force is added, we can compare the pivot point with the center of lateral forces. Finally, we will suggest the center of all lateral forces for maneuvering instead of pivot point. Especially, it will be very helpful for pilots to handle ships in simulation.