• 한국군사과학기술학회지
• /
• 제14권4호
• /
• pp.676-683
• /
• 2011

In this paper, we propose a robust method which can detect and track a high-speed small approaching target in a cluttered environment for Korean Active Protection System. The proposed method uses a temporal and spatial filter, tracking filter to detect and track a single target in consecutive order. And it is comprised of a candidate target detection step, a prior target selection step and a target tracking. Field tests on real infrared image sequences show that the proposed method could stably track a high speed and small target in complex background and target occlusion.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2003년도 ICCAS
• /
• pp.677-680
• /
• 2003

Perceptual landmarks are an effective solution for a mobile robot realizing steady and reliable long distance navigation. But the prerequisite is those landmarks must be detected and recognized robustly at a higher speed under various lighting conditions. This made image processing more complicated so that its speed and reliability can not be both satisfied at the same time. Color based target detection technique can separate target color regions from non-target color regions in an image with a faster speed, and better results were obtained only under good lighting conditions. Moreover, in the case that there are other things with a target color, we have to consider other target features to tell apart the target from them. Such thing always happens when we detect a target with its single character. On the other hand, we can generally search for only one target for each time so that we can not make use of landmarks efficiently, especially when we want to make more landmarks work together. In this paper, by making use of the moment invariants of each landmark, we can not only search specified target from separated color region but also find multi-target at the same time if necessary. This made the finite landmarks carry on more functions. Because moment invariants were easily used with some low level image processing techniques, such as color based target detection and gradient runs based target detection etc, and moment invariants are more reliable features of each target, the ratio of target detection were improved. Some necessary experiments were carried on to verify its robustness and efficiency of this method.

• 제어로봇시스템학회논문지
• /
• 제9권12호
• /
• pp.1033-1041
• /
• 2003

A new visual tracking scheme is proposed for a mobile robot that tracks a moving object in 3D space in real time. Visual tracking is to control a mobile robot to keep a moving target at the center of input image at all time. We made it possible by simplifying the relationship between the 2D image frame captured by a single camera and the 3D workspace frame. To precisely calculate the input vector (orientation and distance) of the mobile robot, the speed vector of the target is determined by eliminating the speed component caused by the camera motion from the speed vector appeared in the input image. The problem of temporary disappearance of the target form the input image is solved by selecting the searching area based on the linear prediction of target motion. The experimental results have shown that the proposed scheme can make a mobile robot successfully follow a moving target in real time.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
• /
• pp.1027-1028
• /
• 2006

In this paper, design of current and speed controller for DC motor drive system using Embedded Target for TI C2000DSP in Matlab/Simulink is introduced. Current and speed controller is designed and implemented using program simply and easily, and speed control response of DC motor can be advanced. Current and speed control of DC motor is carried in eZdsp F2812 control board using Embeded Target for TI C2000DSP in Matlab/Simulink. Speed feedback is processed through A/D converter using tacho generator as speed sensor, and current feedback is processed through A/D converter using hall sensor as current sensor. Controller is designed to PI current controller and PI speed controller. Current and speed response is verified through simulations and experiments.

• 수산해양기술연구
• /
• 제35권3호
• /
• pp.301-311
• /
• 1999

The investigation to evaluate the possible effects of fish behaviour on acoustic target strength was carried out during the 1997 and 1998 hydroacoustic-demersal trawl surveys in the southern waters of Korea.The swimming speed and the target strength of individual, acoustically resolved fished swimming through the sound beam were measured using the split-beam tracking method on board R/V Kaya.The results obtained can be summarized as follows:1. The alongship and athwartship angles between -3dB poionts of a hull mounted 38 kHz split beam tranducer used in these surveys was >$3.76^{\circ}\;and\;6.74^{\circ}$ respectively, and the equal energy contour obtained from the measured beam pattern showed approximately the circular pattern. 2. The swimming speed measured off the south coast of Sorido in 23 January 1997 ranged 0.10 to 0.80 m/s with the average swimming spped of 0.36 m/s, and the target strength ranged -64.8 to -31.7 dB with the average target strength of -52.7 dB. The most dominant species sampled in this survey area were Japanese scaled sardine, Sardinella zunasi and Konoshiro gizzard shad, Konosirus punctatus, respectively.3. The swimming speed measured off the east coast of Kojedo in 24 March 1997 ranged 0.10 to 1.10 m/s with the average swimming speed of 0.40 m/s, and the target strength ranged -64.8 to -51.5 dB with the average target strength of -59.2 dB. The most dominant species sampled in this survey area were Swordtip squid, Photololigo edulis, Konoshiro gizzard shad and Japanese flying squid, Toddarodes pacificus, respectively and the swimming activity of these species seems to be controlled at speeds between 0.20 and 0.60 m/s. 4. The swimming speed measured the south coast of Kojedo in 25 March 1997 ranged 0.10 to 1.40 m/s with the average swimming speed of 0.51 m/s and the target strength ranged -64.3 to -47.7 dB with the average target strength of -55.1 dB. The most dominant species sampled in this survey area were Swordtip squid, Blotchy sillage, Sillago maculata and japanese scaled sardine, respectively and the swimming activity of these species seems to be controlled at speeds between 0.20 and 0.70 m/s.5. The swimming speed measured during morning twilight in the southeastern water of Cheju Island in 11 July 1998 ranged 0.20 to 1.0 m/s with the average swimming speed of 0.53 m/s, and the target strength ranged -65.0 to -47.0 dB with the average target strength of -57.1 dB. The most dominant species sampled in this survey area were Swordtip squid, Black scraper, Thamnaconus modesutus and japanese flying squid, respectively and the tile angle ranged$ +28^{\circ}\;to\;+2^{\circ}$ with the average tilt angle of -8.1$^{\circ}$ showing the downward migration.

• 융합신호처리학회논문지
• /
• 제13권1호
• /
• pp.56-62
• /
• 2012

이 논문은 매트랩/시뮬링크에서 도입한 TI 2000 DSP 라이브러리를 위한 임베디드 타켓을 사용하여 직류 모터 시스템에 대한 속도 제어기를 설계하고 구현하였다. 속도 제이기는 매트랩/시뮬링크 프로그램을 사용하여 쉽게 설계하고 구현할 수 있다. 모터 속도의 궤환은 속도 감지기로 엔코드와 펄스미터를 사용하여 eZdsp F2812 의 A/D 변환기를 통하여 처리하였다. 제어기의 실시간 프로그램은 시뮬링크를 사용하여 그렸고, P 제어기, PID 제어기 그리고 매개변수 추정 을 기반 적응제어기의 변환된 프로그램 코드는 Realsys eZdsp 2812 보드로 다운로드하였다. 그리고 실험을 통하여 구현된 제어기들의 속도응답을 확인하였다. 제어대상이 변경되었을 때에도 제어기를 쉽게 설계 및 구현하는 방법을 연구했다.

• 한국군사과학기술학회지
• /
• 제8권2호
• /
• pp.49-57
• /
• 2005

The target localization using the line arrays buried in the seabed is a difficult problem due to the complex sea bottom characteristics and need to compensate the wave propagation effect to localize the target accurately Sound speed mismatch in the seabed causes a bias in the target bearing estimation and induces the localization error. In this paper we describe a target localization method with improved accuracy of target bearing and localization by calibration the sound speed in the seabed. The proposed algorithm is verified through the ocean data.

• 한국산업정보학회논문지
• /
• 제18권4호
• /
• pp.53-60
• /
• 2013

본 논문에서는 소형표적의 검출속도를 개선하기 위하여, SAD 알고리즘을 이용한 소형표적 검출 방법을 제안한다. 먼저 미디언 필터를 사용해서 클러터를 제거한다. 다음으로 다양한 크기의 구조 요소를 이용해 닫힘 연산과 열림 연산을 수행하고, 닫힘 연산 결과와 열림 연산 결과를 차 연산 하여 표적 후보 화소를 추출한다. 정확한 소형 표적을 검출하기 위해 표적 후보 영역에서 가우시안 거리 함수를 이용하여 표적을 검출한다. 검출 속도를 개선하기 위하여 다음 7프레임에서는 표적의 방향성을 예측한 후, SAD알고리즘을 이용해서 표적을 검출한다. 제안한 방법은 예측된 영역에서만 표적을 추출함으로써 97%의 검출율을 나타내며, 실시간 처리가 가능한 장점을 가지고 있다.

• 한국군사과학기술학회지
• /
• 제12권4호
• /
• pp.500-507
• /
• 2009

This paper presents a novel method which can detect a target in IR image for active protection system. The target in IR image for the active protection system is small, moreover it moves with enormous speed. The proposed algorithm is comprised of robust clutter rejection methods and target optimized detection algorithms for small target, and an advanced method of selecting a final target position in target area, it can work in some milliseconds. The proposed algorithm provides the active protective system with more correct positions than those of radar, so that helps the active protection system can defense all threats with the utmost precision.

• 전기학회논문지
• /
• 제64권3호
• /
• pp.445-450
• /
• 2015

In the moving target problem, the velocity information of the moving target is very important as well as the high accuracy position information. To solve this problem, active researches are being conducted recently with combine the Time Difference of Arrival (TDOA) and Frequency Delay of Arrival(FDOA) measurements. However, since the FDOA measurement is utilizing the Doppler effect due to the relative velocity between the target source and the receiver sensor, it may be difficult to use the FDOA measurement if the moving target speed is not sufficiently fast. In this paper, we propose a method for estimating the position and the velocities of the target by using only the TDOA measurements for the low speed moving target in the indoor environment with sensor network. First, the target position and heading angle are obtained from the estimated positions of two attached transmitters on the target. Then, the target angular and linear velocities are also estimated. In addtion, we apply the Instrumental Variable (IV) technique to compensate the estimation error of the estimated target velocity. In simulation, the performance of the proposed algorithm is verified.