• Journal of Institute of Control, Robotics and Systems
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• v.19 no.2
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• pp.95-101
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• 2013

The paper investigates the geometric effect of landmarks to the navigation error in the landmark based 3D vision navigation and introduces the INS/Vision integrated navigation system considering its effect. The integrated system uses the vision navigation results taking into account the dilution of precision for landmark geometry. Also, the integrated system helps the vision navigation to consider it. An indirect filter with feedback structure is designed, in which the position and the attitude errors are measurements of the filter. Performance of the integrated system is evaluated through the computer simulations. Simulation results show that the proposed algorithm works well and that better performance can be expected when the error characteristics of vision navigation are considered.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2701-2706
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• 2003

This paper describes weld seam tracking and error compensation methods of automatic plasma arc welding system designed for the corrugation panel that consists of a linear section and a curved section with various curvatures. Realizing automatic welding system, we are faced with two problems. One is a precise seam tracking and the other is an arc length control. Due to the complexity of the panel shape, it is difficult to find a seam and operate a torch manually in the welding process. So, laser vision sensor for seam tracking is equipped for sensing the seam position and controlling the height of a torch automatically. To attain more precise measurement of an arc length, we measure the 3D shape of the panel and analyze error factors according to the various panel states and caused errors are predicted through the welding process. Using that result, compensation algorithm is added to that of arc length control and real time error compensation is achieved. The result shows that these two methods work effectively.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.2
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• pp.204-209
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• 2016

The analyses on self-heating effect in 7 nm node non-rectangular Bulk FinFET device were performed using 3D device simulation with consideration to contact via and pad. From self-heating effect simulation, the position where the maximum lattice temperature occurs in Bulk FinFET device was investigated. Through the comparison of thermal resistance at each node, main heat transfer path in Bulk FinFET device can be determined. Self-heating effect with device parameter and operation temperature was also analyzed and compared. In addition, the impact of interconnects which are connected between the device on self-heating effect was investigated.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.11 s.254
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• pp.1408-1416
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• 2006

A mathematical knee model was constructed using MADYMO. The purpose of this study is to present a more realistic model of the human knee to reproduce human knee motion. Knee ligaments were modeled as line elements and the surrounding muscles were considered as passive restraint elements. A calf-free-drop test was performed to validate the suggested model. A calf was dropped from the rest at about 65 degree flexed posture in the prone position. The motion data were recorded using four video cameras and then three dimensional data were acquired by Kwon3D motion analysis software. The results showed that general shapes of angular quantities were similar in both the experiment and computer simulation. Functional stability of the anterior cruciate ligament was explicitly revealed through this model.

• Transactions of Materials Processing
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• v.16 no.2 s.92
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• pp.120-125
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• 2007

Magnesium alloy has low formability at room temperature and therefore, in many cases, forming at elevated temperatures is necessary to obtain the required material flow without failure. Tn the present study, square cup deep drawing tests using the magnesium alloy AE31 sheet were experimentally conducted using the porches and dies with different edge radius to evaluate the formability sensitivity to the die design variables. The experimental results showed that the fracture position over the cup wall moved from the punch nose to the flange as the die temperature increased, and that the drawing depth change was more affected by the punch radius than the die radius.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.272-275
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• 2005

The digital map expresses natural topographies and artificial things with 3D position coordinates in the computer such as the road, railway, building, river, mountain, paddy and dryland. Therefore, the digital map is regarded as an important factor in the information-oriented society. However, it is difficult to maintain the most recent topographic information all the times because of restricted budget and time. For that, the efficient method corresponded with the digital map should be presented. This study aims to suggest the way to make an estimate of updating cost for 1:5,000 scale digital map by using remotely sensed data. To predict updating area of the digital map, the screen digitizing method was applied to the overlapped images and digital maps.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.9
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• pp.846-851
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• 2010

In this paper, we newly propose a novel control strategy of a three joints-robot finger for the purpose of artificial hands. The robot finger is specifically modeled by using a 3D CAD program (CATIA), considering human fingers, and then the proposed control method is verified through the dynamic simulation tool (Simulink and Recurdyn R2). Each slider is individually controlled to be located at the optimal positions where the maximal joint torque can be generated. To prove the effectiveness of the proposed control method, we devise two cases for the reference position of sliders. By comparing the control performance of two cases, the validity of the proposed control method will be verified.

• Journal of the Korean Graphic Arts Communication Society
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• v.28 no.1
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• pp.1-13
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• 2010

Gravure printing and manufacturing of advanced electronic components in a way that is going extra hold position. It is to print the electronic components of the rapid productivity improvements as well as cost-saving and environment-friendly industries such as the transition is a big advantage. However the mechanism of gravure is difficult to study scientifically because of high speed and excessively small size of the cell. To approach the mechanism we experimented using gravure printability. The condition of variables of IGT is pressure and velocity. By using Flow-3D simulation software, we built up the theoretical model under the constant variables. Then, we compared the real test with the simulation results. Therefore, it is studied the mechanism of gravure scientifically and it can be analysed the effect of the variable conditions.

• Proceedings of the KIEE Conference
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• 2004.10a
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• pp.6-8
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• 2004

Recently, the PM type stepping motor preferred solution for many small electronics position determination devices since it is small in size. Thus, there are glowing demands for permanent magnet(PM) type stepping motor that greater mechanical output, smaller size. This paper deals with a study of the miniaturization of the PM type stepping motor with claw-poles. We introduced the small-sized PM type stopping motor that has new structure and analyzed the magnetic characteristic of it versus general type model using 3-D finite element analysis(FEA).

• Journal of the Korean Society for Precision Engineering
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• v.12 no.3
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• pp.23-31
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• 1995

The sending characteristics of the non-contact type displacement transducers can affect the performances of the magnetic bearing systems when they support the rotating shaft. The probe type displacement sensor detects not only the displacement of the rotor at the sensing position but also the surface irregularitis of the rotor such as surface roughnessand roundness errors. If there exist such measuring errors, the magnetic bearing can not apply proper force against the rotor displacements for the detected signal is the input to the magnetic bearing controllers. The cylindrical shape capacitive transducer can detect the rotor displacement by the integral sum of the charges which are formed between the sensor plates and rotor so that it can reduce the detecting errors induced by the surface irregularities of the rotor. By theore- tical analysis, we compared the sensing characteristics of the cylindrical shape capacitive transducers for the rotors that have some sinusoidal irregularities with that of the ideal probe type displacement transducers.