• Journal of Satellite, Information and Communications
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• v.2 no.1
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• pp.21-26
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• 2007

LEO Satellite that observes earth with optical camera or synthetic aperture radar is placed at hundreds of kilometers altitude and undergoes severe thermal load. The thermal deformation of structure by the thermal load makes payload not to point toward wanted ground position. The payload pointing direction change by thermal distortion is called thermal pointing error. This is carried out by 3 steps that are thermal analysis, temperature conversion and structural analysis. In this paper, the possibility of successful mission through thermal pointing error analysis is described.

• Journal of Korea Multimedia Society
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• v.19 no.8
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• pp.1225-1235
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• 2016

This paper presents a method for computer-assisted slide presentation using vision-based gesture recognition. The proposed method consists of a sequence of steps, first detecting a hand in the scene of projector beam, then estimating the smooth trajectory of a hand or a pointing finger using Kalman Filter, and finally interfacing to an application system. Additional slide navigation control includes moving back and forth the pages of the presentation. The proposed method is to help speakers for an effective presentation with natural improved interaction with the computer. In particular, the proposed method of using finger pointing is believed to be more effective than using a laser pointer since the hand, the pointing or finger are more visible and thus can better grab the attention of the audience.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.10a
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• pp.365-370
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• 1999

In this paper, dynamic response analysis on the ground movement applied traffic load by 2D finite element procedure has been studied. In particular, The paper deal with pointing acceleration method that applied AFIMEX Code as like 2D-FLUSH using equivalent linear method. As the result, it is found that dynamic response analysis by pointing acceleration method expressed ground movement by traffic load exactly.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.112-116
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• 1992

In this paper, a fuzzy logic controller(FLC) is designed for the pointing loop of the spin-stabilized platform. For the fuzzy inference, a fuzzy accelerator board using the Togai InfraLogic software and digital fuzzy processor(DFP110FC) is designed, and a validation of an algorithm for fuzzy logic control is also presented. The pointing loop of the spin-stabilized platform using FLC has better performance of step responses than a proportional controller in case of same loop hain through the software simulation and the experiment of implemented hardware.

• Proceedings of the ESK Conference
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• 1996.04a
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• pp.253-258
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• 1996

Virtual reality environment system is expected to be used as a new user interface tool oweing to its high immersiveness and high interactivity. To use VR interface effectively, we should identify the characteristics of the three-dimensional control tasks as if we did in two-dimensional graphic user interface environments. As a first step, we validated Fitts'law for the three-dimensional pointing tasks with the two input devices, Spaceball and Spacemouse. Different from the two-dimensional control tasks, VR pointing tasks needed inclusion of a new variable, size of the moving object, to Fitts'law. The modified

• Aerospace Engineering and Technology
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• v.4 no.1
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• pp.45-48
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• 2005

Study on the thermal pointing error analysis for optical bench was performed in this paper. Spacecraft FEM is necessary to conduct thermal pointing error analysis for optical bench. But generally during the preliminary design, exact spacecraft FEM does not exist. So the analysis method to predict thermal pointing error of spacecraft is necessary without exact spacecraft FEM. In this study, these analysis techniques are described.

• The Journal of Korea Robotics Society
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• v.4 no.2
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• pp.139-146
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• 2009

This paper describes how a person extracts a unknown object with pointing gesture while interacting with a robot. Using a stereo vision sensor, our proposed method consists of two stages: the detection of the operators' face, the estimation of the pointing direction, and the extraction of the pointed object. The operator's face is recognized by using the Haar-like features. And then we estimate the 3D pointing direction from the shoulder-to-hand line. Finally, we segment an unknown object from 3D point clouds in estimated region of interest. On the basis of this proposed method, we implemented an object registration system with our mobile robot and obtained reliable experimental results.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.3
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• pp.297-302
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• 2009

In this paper, we propose advanced screen detector as a tool for selecting the object for tracking and estimating its distance from a screen using fuzzy logic in vision based pointing device. Our system classifies the line component of the input image into horizontal and vertical lines and applies the fuzzy rule to obtain the best line pair which constitute peripheral framework of the screen. The proposed system improves the detection ratio for detecting the screen in relative to the detector used in the previous works for hand-held type vision based pointing device. Also it allows to detect the screen even though a small part of it may be hidden behind other object.

• Journal of the Korea Institute of Military Science and Technology
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• v.4 no.2
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• pp.157-178
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• 2001

In this paper, the nonlinear control of high precision pointing stabilization system using feedback-linearization design methodology based on system parameter identification is discussed. Modern nonlinear servomechanism theory is adapted to cope with the hard nonlinearities inherent in the turret system. The mathematical models of electrical turret driving system to develop a high performance control algorithm are derived, and the parameter estimation algorithm identifying the unknown system parameters such as vicious and coulomb frictions, stiffness and inertia is developed. Through computer simulation and experiments, it is shown that pointing and tracking accuracy and stabilization against the wideband stochastic disturbance induced by vehicle running on the bump course are improved. Therefore, it is considered the proposed nonlinear control technique is effective in counteracting the nonlinearities and disturbances.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.9
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• pp.840-846
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• 2004

In this study, the performance of a heavy load pointing system has been investigated. The PI controller are being widely used in industrial application because of simple, cheap, and excellent performance. However, the requirement for control precision becomes higher and higher, as well as the plants becomes more and more complex. In order to achieve the satisfied control performance, we have to consider the affection of nonlinear factor contained in plant. In this paper, the neural-PI control law have been evaluated. The proposed controller is compared with the existing controllers through simulations, and the results show that the pointing accuracy of the proposed control system is improved against the disturbance induced by vehicle running on the bump course.