• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2001년도 가을 학술발표논문집 Vol.28 No.2 (2)
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• pp.523-525
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• 2001

본 논문은 많은 수의 rigid body 물체들을 물리학에 기반하여 실시간으로 애니메이션하는 방법을 제안한다 rigid body 물체들의 움직임을 생성해내는 과정은 상당한 시간이 소요되며 또한 물체의 수가 증가함에 따라 계산시간이 급증한다. 본 논문에서는 Timewarp rigid body 시뮬레이션 알고리즘을 실시간 애니메이션에 적용하기 위해 시간당 생성되는 프레임 수에 따른 다단계 롤백 범위 적용을 하는 방법을 제안하고 실험을 통하여 시뮬레이tus 시스템의 효율성을 보인다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.1699-1703
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• 2000

While the booming occurs in a cabin, the powertrain and subframes which are the main sources and paths of the booming, show the rigid body motions. This paper presents a technique to predict the booming noise in a car using the rigid body information of the important parts. The rigid body information comes from the CAD data, from which we can predict the response of the complex system. Since the mechanism of this technique is very similar to the finite element formulation, we can apply it to the complex system with ease.

• Journal of Computational Design and Engineering
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• 제1권2호
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• pp.96-102
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• 2014

In the field of design and manufacturing, there are many problems with managing dynamic states of three-dimensional (3D) objects. In order to solve these problems, the four-dimensional (4D) mesh model and its modeling system have been proposed. The 4D mesh model is defined as a 4D object model that is bounded by tetrahedral cells, and can represent spatio-temporal changes of a 3D object continuously. The 4D mesh model helps to solve dynamic problems of 3D models as geometric problems. However, the construction of the 4D mesh model is limited on the time-series 3D voxel data based method. This method is memory-hogging and requires much computing time. In this research, we propose a new method of constructing the 4D mesh model that derives from the 3D mesh model with continuous rigid body movement. This method is realized by making a swept shape of a 3D mesh model in the fourth dimension and its tetrahedralization. Here, the rigid body movement is a screwed movement, which is a combination of translational and rotational movement.

• 대한기관식도과학회지
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• 제5권2호
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• pp.159-163
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• 1999

OBJECTIVE : To study the management (diagnostic and therapeutic) of esophageal foreign bodies with rigid esophagoscopy. MATERIAL AND METHODS : All 100 patients admitted to the Dankook University Hospital for ingestion of foreign bodies between May 1994 and July 1999. The outcome for each patient was determined by examining hospital records of demographic information, identification of the foreign body and the removal procedure used. RESULTS : Rigid esophagoscopy was performed for suspected foreign bodies in 100 cases an impacted. The most frequent location was the upper third of the esophagus (68%). The most common type of foreign body was fish bones in adult(61%) and coins in children(70%). In 12 patients. flexible endoscopy had failed previously to remove the foreign body and 4 cases were migrated esophageal metal stent in esophageal stenosis. CONCLUSIONS : The rigid esophagoscopy is appropriate techniques for managing esophageal foreign bodies.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -2
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• pp.1216-1219
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• 2002

It is understood so far that the center of mass does not make any linear movement from the rotatory movement of a rigid body in the closed system. However, it has been found that the center of mass of the system could make a closed linear movement due to production of an instantaneous center of mass by the Coriolis force in the rotatory movement of a rigid body in the closed system. The nature of the closed linear movement in the non-inertial system and that of the open movement in the inertial system are different from each other. That is, the closed movement is described like the time integration of frictional forces, which is different from the open movement usually considered and described like the time integration of external forces. It is shown in this paper that the Coriolis forces, called a fictitious force in the classical mechanics, is similar to the frictional force so that it causes to move the center of mass of a closed system. In this paper, following an explanation of the closed linear movement of a non-inertial system and the open movement of an inertial system, the source of the closed linear movement phenomenon of a rotatory rigid body is presented.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2022년도 춘계학술대회
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• pp.587-588
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• 2022

본 논문에서는 다수의 모션 캡처 카메라의 2D 패시브마커 영상을 이용한 3차원 공간에서의 리지드 바디(Rigid Body) 추적 방법을 제안한다. 1차로 개별 카메라의 내부 변수를 구하기 위해 체스보드를 이용한 칼리브레이션 과정을 수행하고, 2차 보정 과정에서 3개의 마커가 있는 삼각형 구조물을 모든 카메라가 관찰 가능하도록 움직인 후 프레임별 누적된 데이터를 계산하여 카메라간의 상대적인 위치정보의 보정 및 업데이트를 진행한다. 이 후 각 카메라의 좌표계를 3D월드 좌표계로 변환하는 과정을 통해 3개 마커의 3차원 좌표를 복원하여 각 마커간 거리를 계산하여 실제 거리와의 차이를 비교한 결과 2mm 이내의 오차를 측정하였다.

• Bulletin of the Korean Chemical Society
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• 제26권5호
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• pp.769-775
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• 2005

An efficiency of Monte Carlo (MC) docking simulations was examined for the prediction of chiral discrimination by cyclodextrins. Docking simulations were performed with various computational parameters for the chiral discrimination of a series of 17 enantiomers by $\beta$-cyclodextrin ($\beta$-CD) or by 6-amino-6-deoxy-$\beta$-cyclodextrin (am-$\beta$-CD). A total of 30 sets of enantiomeric complexes were tested to find the optimal simulation parameters for accurate predictions. Rigid-body MC docking simulations gave more accurate predictions than flexible docking simulations. The accuracy was also affected by both the simulation temperature and the kind of force field. The prediction rate of chiral preference was improved by as much as 76.7% when rigid-body MC docking simulations were performed at low-temperatures (100 K) with a sugar22 parameter set in the CHARMM force field. Our approach for MC docking simulations suggested that the conformational rigidity of both the host and guest molecule, due to either the low-temperature or rigid-body docking condition, contributed greatly to the prediction of chiral discrimination.

• 한국기계가공학회지
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• 제21권2호
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• pp.54-63
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• 2022

Among the various industrial robots, palletizing robots have received particular attention because of their higher productivity in accordance with technological progress. When designing a palletizing robot, the main components, such as the servo motors and reducers, should be properly selected to ensure its performance. In this study, a practical method for selecting the motors and reducers of a robot was proposed by performing the dynamic analysis of rigid-flexible multibody systems using ANSYS and ADAMS. In the first step, the links and frames were selected based on the structural analysis results obtained from ANSYS. Subsequently, a modal neutral file (MNF) with information on the flexible body was generated from the links and frames using modal analysis through ANSYS and APDL commands. Through a dynamic analysis of the flexible bodies, the specifications of the major components were finally determined by considering the required torque and power. To verify the effectiveness of the proposed method, the analysis results were compared with those of a rigid-body model. The comparison showed that rigid-flexible multibody dynamic analysis is much more useful than rigid body analysis, particularly for movements heavily influenced by gravity.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.480-485
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• 2005

Perspective dynamical systems arise in machine vision problems, in which only perspective observation is available. This paper considers the state estimation problem for a rigid body moving in three dimensional spaces using the image data obtained by a CCD camera or some other means. Because the motion of the rigid body and the observed data are generally corrupted by noises, it is necessary to seek a state estimation method to reduce the influence of the noises. In this paper, by means of computer simulations for a simple example, we examine the sensitivity to the noises of the nonlinear observer developed in the recent paper ([1] R. Abdursul, H. Inaba and B. Ghosh, Nonlinear observers for perspective time-invariant linear systems, Automatica, vol. 40, Issue 3, pp. 481-490, 2004) and the effectiveness of the Extended Kalman Filter.

• 한국자동차공학회논문집
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• 제1권2호
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• pp.125-133
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• 1993

Electronic Speckle Pattern Interferometry(ESPI) using a CW laser, a video system and image processor was applied to the rotating displacement of rigid body. ESPI require no special surface preparation or attachments and displacements between any two arbitrary points on the surface can be measured. The characteristic speckle pattern formed when imaging a scattering surface illuminated by laser light retains phase information, which can be used for interferometric measurement of surface displacement. The application of this principle to measuring in-plane displacement resolved in one direction is described, together with the novel use of television equipment to detect and process the information contained in the speckle pattern. This is faster, and more convenient and versatile than customary photographic methods.