• 제어로봇시스템학회:학술대회논문집
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• 1990.10b
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• pp.1167-1172
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• 1990

This paper discusses a force distribution scheme which minimizes the weighted norm of the forces/torques applied on weak points of cooperating multiple robot arms. The scheme is proposed to avoid the damage or unwanted motion of any weak point of robots or object stemming from excessive forces/torques. Since the proposed scheme can be used for either the joint torque minimization or the exerted force minimization on the object, it can be regarded as a unified force minimization method for multiple robot arms. The computational complexity in this scheme is analyzed using the properties of Jarcobian. Simulation of two identical PUMA robots held an object is carried out to illustrate the proposed scheme. By the proper choice of the weighting matrix in the performance index, we show that force minimization for a weak point can be achieved, and that the exerted force minimization on the object can be changed to the joint torque minimization.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.34S no.9
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• pp.67-76
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• 1997

This ppaer describes the development of the stereo camera system(KASS-1) and the control of the vergence of the stereo camera to fix a gaze on a moving object in real-time using a stereo disparity. The motion energy and the stereo disparity of a moving object from the stereo image are used to control the vergence of stereo camera to keep stereo disparity constant. The disparity from the rotating stereo camera is introduced not only from the moving object but also from the background. In this paper, the background disparity error due to the vergence control of the stereo camera is eliminated by compensation algoithm, and the vergence of steereo camera system can be controlled continuously using the disparity of a moving object only.

• The Journal of Korea Robotics Society
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• v.1 no.2
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• pp.172-179
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• 2006

In this paper, we present a practical place and object recognition method for guiding visitors in building environments. Recognizing places or objects in real world can be a difficult problem due to motion blur and camera noise. In this work, we present a modeling method based on the bidirectional interaction between places and objects for simultaneous reinforcement for the robust recognition. The unification of visual context including scene context, object context, and temporal context is also. The proposed system has been tested to guide visitors in a large scale building environment (10 topological places, 80 3D objects).

• Journal of the Korea Society of Computer and Information
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• v.12 no.5
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• pp.163-170
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• 2007

In this paper, We propose a new technique for extraction of moving objects included in compressed video signal. Moving object extraction is used in several fields such as contents based retrieval and target tracking. In this paper, in order to extract moving object blocks, motion vectors and DCT coefficients are used selectively. The proposed algorithm has a merit that it is no need of perfect decoding, because it uses only coefficients on the DCT transform domain. We used three test video sequences in the computer simulation, and obtained satisfactory results.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.11
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• pp.1482-1484
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• 2019

We present a method for transmitting 3D object information in real time in a telepresence system. Three-dimensional object information consists of a large amount of point cloud data, which requires high performance computing power and ultra-wideband network transmission environment to process and transmit such a large amount of data in real time. In this paper, multiple users can transmit object motion and facial expression information in real time even in small network bands by using GANs (Generative Adversarial Networks), a non-supervised learning machine learning algorithm, for real-time transmission of 3D point cloud data. In particular, we propose the creation of an object similar to the original using only the feature information of 3D objects using conditional GANs.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.12
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• pp.2762-2770
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• 2012

In this paper, we propose a novel approach to effectively compress the sub-images transformed from the picked-up elemental images in integral imaging, in which motion vectors of the object in each sub-image are fast and accurately estimated and compensated by combined use of MSE(mean square error)-based TSS(tree-step search) and FS(full search) schemes. This is, the possible object areas in each sub-image are searched by using the fast TSS algorithm in advance, then the these selected object areas are fully searched with the accurate FS algorithm. Furthermore, the sub-images in which all object's motion vectors are compensated, are transformed into the residual images by using the difference image method and finally compressed with the MPEG-4 algorithm. Experimental results reveal that the proposed method shows 214% improvement in the compression time per each image frame compared to that of the conventional method while keeping the same compression ratio with the conventional method. These successful results confirm the feasibility of the proposed method in the practical application.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.04a
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• pp.439-446
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• 2004

In this study, the characteristic of the Near Fault Ground Motion which was not considered at the seismic design in our country and how the Near Fault Ground Motion affects the cable-stayed bridge which have long period is analyzed through the dynamic response analysis. So, the object of this study is following that it makes the data which can be utilized as the seismic safety evaluation in case of the cable-stayed bridge taken the near fault in the future.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1078-1081
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• 2004

A robot manipulator is usually operated in two modes: free motion and constraint motion depending on whether the robot comes into contact with the environment or not. At the moment of contact, impact occurs, and sometimes, it possibly degrade the robot's performance by vibration and at worst, shortens its lifetime. In this article, a new proposed algorithm is described by introducing a command signal modification method on the basis of impedance control and a validity of the proposed algorithm is demonstrated by showing a simulation and an experiment.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.11
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• pp.1850-1856
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• 1989

For determining motion/structure of a 3-D rigid object from point correspondences over two perspective views, a linear algorithm was developed in Refs. 3 and 4. This algorithm fails when the 3-D points under observation satisfy certain geometrical constraints, as demonstrated in Refs. 7 and 8. In the present paper, we show that the linear algorithm can be resurrected in these degenerate cases by adding additional lower order polynomial constraints to original equations.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.8
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• pp.41-53
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• 1993

The tasks which detect and track moving objects, by analyzing dynamic images taken at a constant time interval, are essential in various applications. This paper suggests how to utilize domain-specific knowledge and motional knowledge for detecting and tracking moving objects. That is, The trajectory information of a moving object is to be used for generating hypotheses on expected motion and expected position of moving objects, and the domain-specific knowledge is to be used for verifying the generated hypotheses.