• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.310-310
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• 2000

The main problem in stereo vision is to find corresponding points in left and right image known as correspondence problem. Once correspondences determined, the depth information of those points are easily computed form the pairs of points in both image. In this paper, dynamic programming considering half-occluded region is used fer solving correspondence problem.

• ETRI Journal
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• v.26 no.3
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• pp.195-202
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• 2004

In this paper, we propose a visual accessibility technique in an MPEG-21 framework. In particular, MPEG-21 visual accessibility for the colored-visual resource of a digital item is proposed to give better accessibility of color information to people with color vision deficiency (CVD). We propose an adaptation system for CVD as well as a description of CVD in MPEG-21. To verify the usefulness of the proposed method, computer simulations with CVD and color adaptation were performed. Furthermore, a statistical experiment was performed using volunteers with CVD in order to verify the effectiveness of the proposed visual accessibility technique in MPEG-21. Both the experimental and simulation results show that the proposed adaptations technique can provide better color information, particularly to people with CVD.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1816-1819
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• 1997

Using the vision system, robotic tasks in unstructured environments can be accompished, which reduces greatly the cost and steup time for the robotic system to fit to he well-defined and structured working environments. This paper proposes a dynamic control scheme for robot manipulator with eye-in-hand camera configuration. To perfom the tasks defined in the image plane, the camera motion Jacobian (image Jacobian) matrix is used to transform the camera motion to the objection position change. In addition, the dynamic learning controller is designed to improve the tracking performance of robotic system. the proposed control scheme is implemented for tasks of tracking moving objects and shown to outperform the conventional visual servo system in convergence and robustness to parameter uncertainty, disturbances, low sampling rate, etc.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.10
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• pp.822-831
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• 2003

A computer-vision based pipe-inspection algorithm is developed. The algorithm uses the modified Hough transformation and a line-scanning approach to identify the edge line and the radius of the pipe image, from which the eccentricity and dimension of the pipe-end is calculated. Line and circle detection was performed using Laplace operator with input image, which are acquired from the front and side cameras. In order to minimize the memory usage and the processing time, a clustering method with the modified Hough transformation is introduced for line detection. The dimension of inner and outer radius of pipe is calculated by the proposed line-scanning method. The method scans several lines along the X and Y axes, calculating the eccentricity of inner and outer circle, by which pipes with wrong end-shape can be classified and removed.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.15 no.1
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• pp.27-34
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• 2015

For a vision-based driver assistance system, unusual motion detection is one of the important means of preventing accidents. In this paper, we propose a real-time unusual-motion-detection model, which contains two stages: salient region detection and unusual motion detection. In the salient-region-detection stage, we present an improved temporal attention model. In the unusual-motion-detection stage, three kinds of factors, the speed, the motion direction, and the distance, are extracted for detecting unusual motion. A series of experimental results demonstrates the proposed method and shows the feasibility of the proposed model.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.2
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• pp.197-206
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• 2000

A hybrid control structure for vision-based soccer robot system is considered. The structure is om-posed of four levels such as the role action behavior and execution levels. The control structure which is a combination of hierarchical and behavioral structures can efficiently meet the behavior and design specifications of a soccer robot system Among the four levels only the design of the action level is proposed in the paper and is experimentally evaluated. Design hypothesis and evaluation method are presented to improve the reliability and accomplishment of the robot system. Due to the essential element of soccer robot system design a systematic design procedure of the action level is proposed With the proposed structure and algorithm of the action level the excellent result was shown at the MiroSot'98 held in France.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.2
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• pp.152-158
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• 2003

A machine-vision guided inspection system with go-no gauges for inspecting eggcrate assemblies in steam generators is considered. To locate the gauge at the right place, periodic corrective actions for its position and traveling direction are required. We present a machine vision algorithm for determining inserting position and traveling direction of the go-no gauge. The overall procedure of the algorithm is composed of camera calibration, eggcrate image preprocessing, grid-height adjustment, intersection point estimation between two intersecting grids, and adjustment of position and traveling direction of the gauge. The intersection point estimation is performed by using linear regression with a constraint. A test with a real eggcrate specimen shows the feasibility of the algorithm.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.8
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• pp.1104-1110
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• 2014

This paper investigates geometric effect of landmarks on three-dimensional navigation error in landmark-based vision navigation systems. Dilution of precision is derived for landmark measurement error on the focal plane of the camera and separately expressed in position DOP and attitude DOP. Values of DOP are observed for various configurations of landmarks.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.11
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• pp.1017-1021
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• 2004

In this paper, a cost-effective integrated 3D system for measuring and sizing foot is proposed. The proposed system employs two CCDs and a laser line projector which are capable of accurately measuring foot. The measurement is based upon the biologically motivated stereo vision principle providing ruggedness against minor system distortions. According to the tolerance, calibration between two different views are implicitly applied. Furthermore, the measurement system employs a measurement base, a frame grabber, a CCD moving cart, a stepping motor and computer. Analysis and design procedure is presented for the calculation of the 3D foot data and the proposed system. Experimental results on the proposed system would verify the concept and system operation.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.652-657
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• 1991

Up to date, application areas of mobile robots have been expanded. In addition, Many types of LRF(Laser Range Finder) systems have been developed to acquire three dimensional information about unknown environments. However in real world, because of various noises (sunlight, fluorescent light), it is difficult to separate reflected laser light from these noise. To overcome the previous restriction, we have developed a new type vision system which enables a mobile robot to measure the distance to a object located 1-5 (m) ahead with an error than 2%. The separation and detection algorithm used in this system consists of pulse phase difference method and multi-stripe structured light. The effectiveness and feasibility of the proposed vision system are demonstrated by 3-D maps of detected objects and computation time analysis.