• Transactions of the Korean Society of Automotive Engineers
• /
• v.13 no.4
• /
• pp.97-104
• /
• 2005

Vision-based lane sensing systems require accurate and robust sensing performance in lane detection. Besides, there exists trade-off between the computational burden and processor cost, which should be considered for implementing the systems in passenger cars. In this paper, a stereo vision-based lane detection system is developed with considering sensor configuration aspects. An inverse perspective mapping method is formulated based on the relative correspondence between the left and right cameras so that the 3-dimensional road geometry can be reconstructed in a robust manner. A new monitoring model for estimating the road geometry parameters is constructed to reduce the number of the measured signals. The selection of the sensor configuration and specifications is investigated by utilizing the characteristics of standard highways. Based on the sensor configurations, it is shown that appropriate sensing region on the camera image coordinate can be determined. The proposed system is implemented on a passenger car and verified experimentally.

• Journal of Korea Multimedia Society
• /
• v.15 no.6
• /
• pp.711-721
• /
• 2012

The objective of this study is to propose an efficient 3D reconstruction method for developing a stereo-vision-based haptics system which can replace "robotic eyes" and "robotic touch." The haptic rendering for 3D images requires to capture depth information and edge information of stereo images. This paper proposes the 3D reconstruction methods using LoG(Laplacian of Gaussian) algorithm and DoG(Difference of Gaussian) algorithm for edge detection in addition to the basic 3D depth extraction method for better haptic rendering. Also, some experiments are performed for evaluating the CPU time and the error rates of those methods. The experimental results lead us to conclude that the DoG method is more efficient for haptic rendering. This paper may contribute to investigate the effective methods for 3D image reconstruction such as in improving the performance of mobile patrol robots.

• Proceedings of the KSRS Conference
• /
• 2002.10a
• /
• pp.516-516
• /
• 2002

With the wide usage of LiDAR data and high-resolution satellite image, 3D modeling of buildings in urban areas has become an important research topic in the photogrammetry and computer vision field for many years. However the previous modeling has its limitations of merely texturing the image to the DSM surface of the study area and does not represent the relief of building surfaces. This study is focused on presenting a system of realistic 3D building modeling from consecutive stereo image sequences using digital camera. Generally when acquiring images through camera, various parameters such as zooming, focus, and attitude are necessary to extract accurate results, which in certain cases, some parameters have to be rectified. It is, however, not always possible or practical to precisely estimate or rectify the information of camera positions or attitudes. In this research, we constructed the collinearity condition of stereo images through extracting the distinctive points from stereo image sequence. In addition, we executed image matching with Graph Cut method, which has a very high accuracy. This system successfully performed the realistic modeling of building with a good visual quality. From the study, we concluded that 3D building modeling of city area could be acquired more realistically.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.11a
• /
• pp.357-358
• /
• 2006

Accurate calibration matching for maladjusted stereo cameras with calibrated pixel distance parameter is presented. The camera calibration is a necessary procedure for stereo vision-based depth computation. Intra and extra parameters should be obtain to determine the relation between image and world coordination through experiment. One difficulty is in camera alignment for parallel installation: placing two CCD arrays in a plane. No effective methods for such alignment have been presented before. Some amount of depth error caused from such non-parallel installation of cameras is inevitable. If the pixel distance parameter which is one of Intra parameter is calibrated with known points, such error can be compensated in some amount and showed the variable experiments for accurate effects.

• 제어로봇시스템학회:학술대회논문집
• /
• 1993.10a
• /
• pp.692-698
• /
• 1993

This paper presents a Bin-Picking method in which robot recognizes the positions and orientations of jumbled objects placed in a bin, then picks up distinctive objects from the top of the jumble. The jumbled objects are recognized comparing the characteristics extracted from stereo images with those in the CAD data. The 3-D information is obtained using the bipartite-matching method which compares image of one camera with the image of the other camera Then the robot picks up the object which will cause the least amount of disturbance to the jumble, and places it at a predetermined place. This paper contributes to the basic study of Bin-Picking, and can be used in an automatic assembly system without using part sorting or orienting devices.

• Proceedings of the KIEE Conference
• /
• 2005.10b
• /
• pp.603-605
• /
• 2005

In this paper, we deal with a calibration method for low cost motion capture sensor using PSD (Position Sensitive Detection). The PSD sensor is employed to measure the direction of incident light from moving markers attached to motion body. To calibrate the PSD optical module, a conventional camera calibration algorithm introduced by Tsai. The 3-dimensional positions of the markers are measured by using stereo camera geometry. From the experimental results, the low cost motion capture sensor can be used in a real time system.

• Journal of Institute of Control, Robotics and Systems
• /
• v.13 no.3
• /
• pp.224-229
• /
• 2007

This paper presents a camera calibration method using several images for three dimensional measurement applications such as stereo systems, mobile robots, and visual inspection systems in factories. Conventional calibration methods that use single image suffer from errors related to reference point extraction in image, lens distortion, and numerical analysis of nonlinear optimization. The camera parameter values obtained from images of same camera is not same even though we use same calibration method. The camera parameters that are obtained from several images of different view for a calibration target is usaully not same with large error values and we can not assume a special probabilistic distribution when we estimate the parameter values. In this paper, the median value of camera parameters from several images is used to improve estimation of the camera values in an iterative step with nonlinear optimization. The proposed method is proved by experiments using real images.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2009.01a
• /
• pp.566-571
• /
• 2009

A calibration method for multiple sets of stereo vision cameras is proposed. To measure the three-dimensional shape of a very long object, measuring the object at different viewpoints and registration of the data are necessary. In this study, two lasers beams generate two strings of calibration targets, which form straight lines in the world coordinate system. An evaluation function is defined to calculate the sum of the squares of the distances between each transformed target and the fitted line representing the laser beam to each target, and the distances between points appearing in the data sets of two adjacent viewpoints. The calculation process for the approximation method based on data linearity is presented. The experimental results show the effectiveness of the method.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• v.11 no.2
• /
• pp.387-391
• /
• 2006

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.05a
• /
• pp.275-275
• /
• 2004

현재 국가 간의 경쟁력 확보를 위하여 자동화 기술의 개발을 통한 무인화ㆍ자동화를 실현함으로써 물류비용 및 인건비의 절감을 위한 노력에 많은 투자가 이루어지고 있는 실정이다 FMS를 구축하기 위해서는 AGV는 반드시 필요한 운송 장치로 현재 많은 제품들이 생산되어 현장에서 사용되고 있다. 현재 AGV는 바닥에 설치되어 있는 주행라인을 따라서 이동하는 방식이 가장 많이 사용되고 있으며, 주행라인 검출 방식으로 말이 사용되고 있는 전자유도 방식은 설비비용이 말이 들고 경로 수정이 어렵다는 문제점을 가지고 있다.(중략)