• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.20 no.9
• /
• pp.45-53
• /
• 2006

This paper proposes a method for an effective intelligent route decision for automatic moving robots(AMR) using a 2D spatial map of a stereo camera system. In this method, information about depth and disparity map are detected in the inputting images of a parallel stereo camera. The distance between the automatic moving robot and the obstacle is detected, and a 2D spatial map is obtained from the location coordinates. Then the relative distances between the obstacle and other objects are deduced. The robot move automatically by effective and intelligent route decision using the obtained 2D spatial map. From experiments on robot driving with 240 frames of stereo images, it was found that the error ratio of the calculated distance to the measured distance between objects was very low, 1.52[%] on average.

• International Journal of Internet, Broadcasting and Communication
• /
• v.8 no.4
• /
• pp.54-57
• /
• 2016

In this paper, the method for an effective and intelligent route decision of the automatic ground vehicle (AGV) using a 2D spatial map of the stereo camera system is proposed. The depth information and disparity map are detected in the inputting images of a parallel stereo camera. The distance between the automatic moving robot and the obstacle detected and the 2D spatial map obtained from the location coordinates, and then the relative distance between the obstacle and the other objects obtained from them. The AGV moves automatically by effective and intelligent route decision using the obtained 2D spatial map. From some experiments on robot driving with 480 frames of the stereo images, it is analyzed that error ratio between the calculated and measured values of the distance between the objects is found to be very low value of 1.57% on average, respectably.

• Journal of the Korean Ceramic Society
• /
• v.36 no.4
• /
• pp.444-450
• /
• 1999

Hydroxyapatite(HA) was spray-coated to alloy substrate(Ti-6Al-4V) using plasma-spray process for bioceramic application The coating morphology composition and crystallinity were influenced by following process parameters ; stand-off distance spray power level and auxiliary gas pressure. These parameters have been systematically varied in the present study to evaluate their relative influence on the coating qual-ity and to seek an optimum spraying condition. Amorphicity and decomposition of HA increased with stand-off distance and the imperfect coating layer was obtained at the short stant-off distance (55mm). The cry-stallinity of HA coating decreased with spray power level and auxiliary gas pressure but the bond strength between the HA coated layer and Ti alloy substrate increased with the spray power level.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.10 no.5
• /
• pp.206-213
• /
• 2002

This paper proposes a vehicle trajectory prediction method for application to vehicle-to-vehicle distance control. This method is based on 2-dimensional kinematics and a Kalman filter has been used to estimate acceleration of the object vehicle. The simulation results using the proposed control method show that the relative distance characteristics can be improved via the trajectory prediction method compared to the customary vehicle stop and go cruise control systems which makes the vehicle remain at a safe distance from a preceding vehicle according to the driver's preference, automatically slow down and come to a full stop behind a preceding vehicle.

• Journal of Welding and Joining
• /
• v.16 no.3
• /
• pp.44-54
• /
• 1998

In this study a new arc sensor algorithm for automatic weld seam tracking was proposed, which uses the relative welding current variation according to the tip-to-workpiece distance in GMA welding. Since the new developed arc sensor algorithm is not sensitive to unstable factors of arc signal, the system is expected to get rid of the problems of already existing arc sensor system which include the difficulty of modeling the process for various welding conditions and limitation of application to thick plate welding. Thus the system is applicable not only to thick plate welding but also to thin plate welding. To implement the new arc sensor algorithm the system parameters which include sampling time, averaging range, weighting factor of moving averaging, basic compensation time, and basic compensation distance were determined by experimental analysis. Consequently this system has shown the successful tracking capability for the various welding conditions.

• 제어로봇시스템학회:학술대회논문집
• /
• 2001.10a
• /
• pp.53.5-53
• /
• 2001

In continuous galvanizing process at steel making plant, coating weight on the surface of strip that pass through air knife is controlled by the pressure at the chamber of air knife and the gap between the nozzle of air knife and strip. The pressure can be easily measured and controlled. But it is difficult to measure the distance between Air knife nozzle and strip, and also difficult to decide how much distance air knife move. Because, the gap between nozzle and strip varies with the height of air knife, intermesh of stabilizing roll and welding of strips that have different thickness. In this research, we developed a gap sensor that can measure the relative distance between Air knife nozzle and strip. And several tests are performed to find optimal condition for application at real plant. We performed test in which the possibility of the sensor to apply ...

• Journal of Bio-Environment Control
• /
• v.12 no.1
• /
• pp.12-16
• /
• 2003

The effect of humidifying methods on the mean size of droplets ejected from humidifier and distributions of relative humidity in a graft-taking enhancement system (GTES) was investigated. The mean sizes of droplets ejected from an ultrasonic humidifier and a steam humidifier with electrodes were 7.58$\pm$0.14 and 9.01$\pm$0.06 $\mu$m, respectively. Assuming that the particles ejected from humidifiers were mutually combined with distance, the mean diameter of droplets became larger as the distance apart from the outlet of humidifiers increased. When the relative humidity in GRS was controlled at 90％ using the ultrasonic humidifiers, the average relative humidity at the height of 0.4, 1.1 and 1.8 m were 92.1$\pm$5.3, 90.9$\pm$5.6, and 89.7$\pm$6.8%, respectively. However, the average relative humidity using the steam humidifier with electrodes showed 93.4 $\pm$5.4, 90.7$\pm$5.9, and 89.3$\pm$7.0%, respectively. Therefore, it was concluded that humidification by ultrasonic humidifier would be appropriate for the uniform distribution of relative humidity in GTES.

• Journal of Korea Multimedia Society
• /
• v.17 no.9
• /
• pp.1092-1097
• /
• 2014

It is difficult to perform automatic formation flight of UAV (Unmanned Aerial vehicle) when GPS (Global Positionig System) is out of order or has a system error, since the relative position estimation in the flight group is impossible in that case. In this paper, we design a relative localization system for the automatic formation flight of UAV. For this purpose, we adopt digital beam forming (DBF) to estimate the angle with the central controller of the flight group and Particle Filtering scheme to compensate the estimation error of ToA (time of arrival) method. Computer simulation results present a proper distance between the central controller and a following unit to maintain the automatic formation flight.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.50 no.7
• /
• pp.350-353
• /
• 2001

In general, the Least Square Error method is used for signal classification to measure distance in the $l^2$ metric or the $L^2$ metric space. A defect of the Least Square Error method is that it does not classify properly some waveforms, which is due to the property of the Least Square Error method: the global analysis. This paper proposes a new linear operator, the Integra-Normalizer, that removes the problem. The Integra-Normalizer possesses excellent property that measures the degree of relative similarity between signals by expanding the functional space with removing the restriction on the functional space inherited by the Least Square Error method. The Integra-Normalizer shows superiority to the Least Square Error method in measuring the relative similarity among one dimensional waveforms.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2006.05a
• /
• pp.278-281
• /
• 2006

The aims of this study are to investigate rib geometries of reinforcing bars commercially available in Korea, Japan and USA, and evaluate bond performance using beam-end test specimens. Measurement of rib geometries of the bars include nominal area, average distance of rib, height of rib and an angle of rib perpendicular to bar axis. The result of this study show that rib height of Korean reinforcement bars are much less than those of Japan and USA resulting in the lowest value of relative rib area. Average bond strength of Korean D25 deformed bars is known as 9 % less than that of bars produced in USA. Bond strength depends primarily on the relative rib area. Bond strength of the high relative rib area bars produced in USA show 18% higher than that of bars produced in Korea.