• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.175-175
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• 2000

In this Paper we propose a navigation algorithm which can be used to estimate state vectors such as position and velocity for its motion control using multi-sensor output measurements. The output measurement we will use in estimating the state is a series of known multi-sensor asynchronous outputs with measurement noise. This paper investigates the Extended Kalman Filtering method to merge asynchronous heading, heading rate, velocity of DVL, and SSBL information to produce a single state vector. Different complexity of Kalman Filter, with biases and measurement noise, are investigated with theoretically data from KRISO's AUV. All levels of complexity of the Kalman Filters are shown to be much more close and smooth to real trajectories then the basic underwater acoustic navigation system comment)'used aboard underwater vehicle.

• 제어로봇시스템학회논문지
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• 제5권4호
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• pp.437-445
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• 1999

Most autonomous mobile robots view only things in front of then, and as a result, they may collide with objects moving from the side or behind. To overcome this problem, an active omni-directional range sensor system has been built that can obtain an omni-directional depth map through the use of a laser conic plane and a conic mirror. In the navigation of the mobile robot, the proposed sensor system produces a laser conic plane by rotating the laser point source at high speed: this creates a two-dimensional depth map, in real time, once an image is captured. The results obtained from experiment show that the proposed sensor system is very efficient, and can be utilized for navigation of mobile robot in an unknown environment.

• 전기학회논문지
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• 제59권9호
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• pp.1692-1698
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• 2010

In this paper we use wireless sensor network and ultrasonic sensors to estimate local position of mobile robots, and to navigate it. Ultra sonic sensor is simple and accurate so it is good to use in local estimation and navigation of mobile robots. But to obtain accurate distance of two sensors they need to face each others as possible as they can. To solve this problem we rotate ultra sonic sensor which is attached to robot in 360 degrees and obtain accurate distance. We can estimate precise position of mobile robot by triangulation using obtained distance information. A mobile robot navigates using embedded encoder and compensates its coordinates by ultrasonic sensors. Results of Experiments show proposed method obtains accurate distance between sensors and coordinates of position of robot. And mobile robots can navigate designated path well.

• 대한전자공학회논문지TE
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• 제42권4호
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• pp.33-40
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• 2005

본 논문에서는 이동 로봇 주위의 환경 인식과 자기 위치 인식을 위하여 초음파 센서와 한 개의 카메라를 이용하여 안정적인 이동 경로를 확보할 수 있는 방식을 제시하였다. 개발된 초음파 센서(SRF04)시스템은 주행환경의 지도 작성을 위하여 목표물의 특징 데이터를 작성하고, SDC313(SAMSUNG) 카메라에서 수집된 영상자료와 결합하도록 하여 안정적인 경로탐색이 가능한 이동로봇 제어방식을 실험을 통하여 구현하였다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2009년도 공동학술대회
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• pp.496-497
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• 2009

This paper describes about the realization of a remote RF sensor system and its applications. RF Sensor System was designed and realized on DSP over the range of high frequency such as about 200[KHz]. It should be "wireless", "implantable" and "batteryless". Futhermore, the system should be consist of passive components such as R, Land C. The measurement was given using the inductive coupling principle between primary source part and secondary sensor part. This newly developed parameter estimation system can be easily applied to the Ambient Intelligent System including the ubiquitous computing and the sensitive environmental changes.

• 한국산업융합학회 논문집
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• 제20권2호
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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.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2033-2038
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• 2003

This paper describes an integrated navigation strategy for the autonomous service robot PSR. The PSR is under development at the KIST for service tasks in indoor public environments. The PSR is a multi-functional mobile-manipulator typed agent, which works in daily life. Major advantages of proposed navigation are as follows: 1) Structured control architecture for a systematic integration of various software modules. A Petri net based configuration design enables stable control flow of a robot. 2) A range sensor based generalized scheme of navigation. Any range sensor can be selectively applied using the proposed navigation scheme. 3) No need for modification of environments. (No use of artificial landmarks.) 4) Hybrid approaches combining reactive behavior as well as deliberative planner, and local grid maps as well as global topological maps. A presented experimental result shows that the proposed navigation scheme is useful for mobile service robot in practical applications.

• Journal of Positioning, Navigation, and Timing
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• 제13권1호
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• pp.75-83
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• 2024

In order to reduce the time and cost of developing a navigation system, a performance evaluation platform can be used. A User Interface (UI) is required to effectively evaluate the performance, which sets parameters and gives navigation sensor signals and data display, and also displays navigation results. In this paper, a LabVIEW-based UI design method for multi-integrated navigation systems is proposed and implementation results are presented. The UI consists of a signal and data generation part and a signal and data processing part. The signal and data generation part sets parameters for the signal and data generation and displays the navigation sensor signal and data generation results. The signal and data processing part sets parameters for the signal and data processing and displays the navigation results. The signal and data generation part and signal and data processing part are designed to satisfy the requirements of the UI for a performance evaluation of the navigation system. In order to show the usefulness of the proposed UI design method, parameters of the signal and data generation and the signal and data processing are set through the LabVIEW-based UI, and the Global Positioning System (GPS) signal and inertial measurement unit data generation results and the navigation results of a GPS Software Defined Receiver (SDR) and inertial navigation system are confirmed. The implementation results show that the proposed UI design method helps users conduct an effective performance evaluation of navigation systems.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권10호
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• pp.3965-3982
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• 2015

Event detection is one of the key issues in many wireless sensor network (WSN) applications. The uncertainties that are derived from the instability of sensor node, measurement noise and incomplete sampling would influence the performance of event detection to a large degree. Many of the present researches described the sensor readings with crisp values, which cannot adequately handle the uncertainties inhered in the imprecise sensor readings. In this paper, a fault-tolerant event detection algorithm is proposed based on Dempster-Shafer (D-S) theory (also called evidence theory). Instead of crisp values, all possible states of the event are represented by the Basic Probability Assignment (BPA) functions, with which the output of each sensor node are characterized as weighted evidences. The combination rule was subsequently applied on each sensor node to fuse the evidences gathered from the neighboring nodes to make the final decision on whether the event occurs. Simulation results show that even 20% nodes are faulty, the accuracy of the proposed algorithm is around 80% for event region detection. Moreover, 97% of the error readings have been corrected, and an improved detection capability at the boundary of the event region is gained by 75%. The proposed algorithm can enhance the detection accuracy of the event region even in high error-rate environment, which reflects good reliability and robustness. The proposed algorithm is also applicable to boundary detection as it performs well at the boundary of the event.

• 한국군사과학기술학회지
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• 제22권2호
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• pp.189-196
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• 2019

The inertial sensor errors in SDINS(Strapdown Inertial Navigation System) can be compensated by rotating the inertial measurement unit and it is called RINS(Rotational Inertial Navigation System). It is assumed that the error of the inertial sensor in RINS is a static bias. However, the error of the inertial sensor actually developed and produced is not a static bias due to the change of the temperature applied to the sensor and the influence of the earth's gravity acceleration. In this paper, we propose a six-position gyro bias calibration method to evaluate the gyro bias required for RINS and present the test results of applying it to a ring laser gyro inertial navigation system under development.