• Journal of Sensor Science and Technology
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• v.19 no.4
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• pp.278-284
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• 2010

Indoor localization for pedestrian is the key technology for caring the elderly, the visually impaired and the handicapped in health care districts. It also becomes essential for the emergency responders where the GPS signal is not available. This paper presents newly developed pedestrian localization system using the gyro sensors, the magnetic compass and pressure sensors. Instead of using the accelerometer, the pedestrian gait is estimated from the gyro sensor measurements and the travel distance is estimated based on the gait kinematics. Fusing the gyro information and the magnetic compass information for heading angle estimation is presented with the error covariance analysis. A pressure sensor is used to identify the floor the pedestrian is walking on. A complete ambulatory system is implemented which estimates the pedestrian's 3D position and the heading.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.30 no.3
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• pp.182-188
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• 1994

In recent years, navigational and fisheries instruments are rapidly advancing. Especially data processing. data transferring and data interchange throughout the digital signals has been in high progress. Even though the ship's heading is also provided by a gyro-compass, an electro-magnetic compass studying by us currently is easy to issue adequate data to instruments requiring the information for the ship's heading. especially in small fishing boats. As the main element of the electro-magnetic compass is a three-axis magnetic sensors, the developing of the high performance sensor is in highly necessity in the beginning. This paper describes on the development of electro-magnetic compass of three-axis fixed type by using three-axis detection new type magnetic sensor without gimbals. even though usual electro-magnetic compass have to need necessarily a gimbal system in order to keep horizontal condition of the compass.

• Journal of the Korean Institute of Navigation
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• v.4 no.1
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• pp.31-50
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• 1980

It does not seem necessarily practicable to keep the system always in optimal condition, athough the control system of the follow-up mechanism on the most marine gyro compasses is to be adjusted by the operator through the gain adjustment. Sometimes a sustained oscillation or an incorrect gyro reading occurs to the system. For such a system any systematical research or theoretical basis of the guide for the optimal gain adjustment has not been reported yet. As a basic investigation of the theoretical system analysis to solve the problems concerned, the author attempts in this paper to express the system in a mathematical model deduced from the results of the theoretical approach and the experimental observation of each element contained in the follow-up mechanism of Hokshin D-1 gyro compass, and to constitute an over-all closed loop transfer function. This funciton being reverted to a fourth orderlinear differential equation, the first order simultaneous differential equations are obtained by means of the state-variables. The latter equations are solved by the Runge-Kutta method with digital computer. By comparing the characteristic of the simulated over-all output with that of the experimental result, it is shown that both outputs are nearly consistent with each other. It is also expected that the system representation proposed by this paper is valid and will be a prospective means in a further study on the design and optimal adjustment of the system.

• Journal of the Korean Institute of Intelligent Systems
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• v.20 no.6
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• pp.814-819
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• 2010

This paper is presented to study the error minimization of angular velocity for AGV(autonomous ground vehicle). The error minimization of angular velocity is related to localization technique which is the most important technique for autonomous vehicle. Accelerometer, yaw gyro and electronic compass have been used to measure angular velocity. And methods for error minimization of angular velocity have been actively studied through probabilistic methods and sensor fusion for AGVs. However, those sensors still occure accumulated error by mathematical error, system characters of each sensor, and computational cost are increased greatly when several sensor are used to correct accumulated error. Therefore, this paper studies about error minimization of angular velocity that just uses encoder and gyro. To experiment, we use autonomous vehicle which is made by ourselves. In experimental result, we verified that the localization error of proposed method has even less than the localization errors which we just used encoder and gyro respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.35 no.1
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• pp.11-18
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• 1999

In order to secure accuracy and effectiveness of the electromagnetic compass as information sensor for ship's head up bearing with gyro compass, magnetic compass and electromagnetic compass on the sea and on the dock in land.The results obtained were as follows;1. Between the Northeast and the southsouthwest the deviation on ship's head up bearing on electromagnetic compass got easterly deviation with max. $53^{\cire}$on the East and between the Southwest and the Northnortheast westerly deviation with max. $34^{\cire}$ on the Northwest, of which values were not able to be corrected due to the angle excess of deviation adjustment.2. The varies of deviation seemed to have a tendency to increase easterly deviation on the Northeast and the East, easterly deviation after westerly deviation between the South and the Northwest, small one on the North and the Southeast.3. The varies of deviation of ship were larger than the one of around the dock, were extreme on the bow of forecastle deck and were stable on the ship's center line of compass deck at the dock in land.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.4
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• pp.319-327
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• 2004

The Electronic compass made as a pilot model in this research is comprised of a three axis magnetic sensor, an accustar clinometer, and a fiber optic gyro sensor. The results confirming the output character, performance, and the accuracy of the deviation corrects of each sensor are as follows: 1) As for the output character of the three axis magnetic sensor, the magnetic field showed a cosine curve on the X axis, a - sine curve on the Y axis, and constant figures on the Z sensor. The horizontal component H and the vertical component V of the terrestrial magnetism calculated from the output voltage were 33.2${\mu}$T and 23.95${\mu}$T respectively. 2) When the fiber optic gyro sensor is fixed on the electromotive rotation transformation and has made a clockwise rotation with the speed of 10/sec, 20/sec, and 30/sec, the relationship between the output and the rotation angle of the fiber optic gyro sensor showed proportionally constant values. 3) When the magnetic field was induced with a magnet, the deviation before the correction was significant at a high of 25. However, the deviation after the correction using Poisson correction was in the 2 range, significantly lower than before the correction. It was confirmed that automatic deviation corrects are possible with the electronic compass made as a pilot model in this research.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1429-1432
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• 2005

This work is towards the development of a low-cost, small-sized inertial navigation system(INS) which consists of 3 accelerometers, 3 semiconductor gyros and a magnetic compass sensor. This paper explains in detail the structure of the developed system and proposes a 3 dimensional attitude estimation algorithm with Indirect Kalman Filter. The experiments are performed with the developed system attached to a 6 DOF robot for showing the effectiveness of the algorithm.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.29 no.1
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• pp.21-29
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• 1993

The magnetic compass as a principal navigational instrument has been long used to fix ship's position and to determine ship's course. Particularly, in the small fishing vessels the studies on performance and rational usages for magnetic compass are requried to improve the safety and productivity of the small fishing vessels even though gyro compass is developed nowadays. For this purpose, the author examined the present condition of the magnetic compasses which are intalled on 219 small fishing vessels, and carried out a series of performance survey for each compass of them and also found the measured values of deviation by installation position of compass, respectively. The results obtained are summarized as follows: 1. The small fishing vessels less than 4 tons among the 219 small fishing vessels from 1 to 10 tons investigated were 50% of them. Only 1% of them were equipped with the deviation correctors, and 14 fishing vessels used the magnetic compasses which are more than 20 years old. 2. According to the compass installation position, the measured values of the deviation of the compass installed on the top bridge and the compass bed in bridge were ascertained to be the smallest, and those values of the compass installed on the bridge deck above engine room were larger and irregular. 3. The concomitant angle of the magnetic compasses installed on the experimented 4 fishing vessels were measured to be 6$^{\circ}$ to 16$^{\circ}$ and not accorded with the Korean standard values.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.64.4-64
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• 2001

Localization is the key role in controlling the Mobile Robot. In this papers, a development of the sensor fusion algorithm for controling UTV(Unmanned Tracked Vehicle) is presented. The multi-sensocial dead-rocking subsystem is established based on the optimal filtering by first fusing heading angle reading from a magnetic compass, a rate-gyro and two encoders mouned on the robot wheels, thereby computing the deat-reckoned location. These data and the position data provoded by LBL system are fused together by means of an extended Kalman filter. This algorithm is proved by simulation studies.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.8
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• pp.1615-1622
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• 2016

This research aims to develop a voyage performance monitoring system based on international standards. The developed system is equipped with an electronic navigational chart(ENC) that provides onshore and offshore information, as well as supports standardized interfaces with navigational equipment, such as a gyro compass, a differential global positioning system(DGPS), and an automatic identification system(AIS), to monitor the navigation route in real time. In addition, the proposed system adopts a car navigation system to provide a graphical user interface, an intuitive menu-driven configuration, and an easy guide for safer sea navigation. The system, interfaced with the gyro compass and DGPS, was verified without any data loss, and passed a test conducted under extreme conditions by the Korea Laboratory Accreditation Scheme(KOLAS). Finally, the system contributes to preventing collision of vessels and minimizing casualties by maximizing the convenience of mariners which a conventional system does not provide.