• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.10a
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• pp.201-206
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• 2004

Laser scanner are getting used for inspection and reverse engineering in industry such as motors, electronic products, dies and molds. However, due to the lack of efficient scanning technique, the tasks become limited to the low accuracy purpose. The main reasons for this limitation for usefulness are caused from the optical drawback, such as irregular reflection, scanning direction normal to measuring surface, the influence of surface integrity, and other optical disturbances. To overcome these drawback of laser scanner, this study propose the mechanism to reduce the optical trouble by using the 2 kinds of rotational movement axis and by composing the spherical coordinate to scanning the surface keeping normal direction consistently. So, it could be designed and interfaced the measuring device to realize that mechanism, and then it could acquisite the accurate 3D form cloud data. Also, these data are compared with the standard master ball and the data acquisited from the touch point sensor, to evaluate the accuracy and stability of measurement and to demonstrate the implementation of an dental tooth purpose system

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.10a
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• pp.358-362
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• 2004

Higher productivity requires high-speed motion of machine tool axes. The iron core linear DC motor (LDM) is widely accepted as a viable candidate for high-speed machine tool feed unit. LDM, however, has two inherent disturbance force components, namely cogging and thrust force ripple. These disturbance forces directly affect the tracking accuracy of the feeding system and must be eliminated or reduced. In order to reduce motor ripple, this research adapted the feedforward compensation method and neural network control. Experiments carried out with the linear motor test setup show that these control methods are effective in reducing motor ripple.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.10a
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• pp.326-333
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• 2004

This paper presents the structural characteristics analysis of a high-speed horizontal machining center with spindle speed of 50, 000rpm and feedrate of 120m/min. The spindle system is designed based on the built-in motor, angular contact ceramic ball bearings, oil-air lubrication and oil-jacket cooling method. The X-axis and Y-axis feeding systems are composed of the linear motor and linear motion guides, and the Z-axis feeding system is composed of the servo-motor, ball screw and linear motion guide. The structural analysis model of the high-speed horizontal machining center is constructed by the finite element method, and the validity of structural design is estimated based on the structural deformation of the high-speed horizontal machining center and spindle nose caused by the gravity and inertia forces.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.10a
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• pp.363-368
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• 2004

Due to various advantages over the conventional linear motion device such as ball-screw, linear motors have been used in wide variety of industrial applications for years. Driven by increased demand for precision machine tools, the importance of high positioning accuracy, high stiffness and high thrust are greatly increasing. The merits of linear motor are high speed, high acceleration and good positioning accurcy. In addition, Linear motor for high quality machine tool call for high thrust, high stiffness. In this paper, thrust ripple, detent force and thermal behavior are considered for the development of high performance linear motor whose thrust is up to 10,000N. This paper presents a comprehensive study for an iron core type linear motor characteristics that include the influence of PM position on thrust, thrust ripple by detent force and motor dynamics as well.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1193-1197
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• 2008

Bridge is Most from stay of Gantry structures part. In compliance with oneself weight of the bridge deflecting, this occurs drops the location precision of the work tool. Also accelerative at the time of gives a serious load to Y axial motors which transfer the bridge damages. The motor with high-speed transfer of location control which is accurate makes disrupt. The malleability of the bridge to maintain consequently and necessary to minimize a weight. This paper the structural FEM interpretations of the stone and the aluminum alloy with the material by which will be used in the bridge and static deflected and a candle precise plane X-Y stage optimal design with character the interpretation result.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.990-995
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• 2008

During the ship's construction process, most high place workings have been carried out by human power, like welding, grinding and so on. Because of the ability to relieve human beings from these, the need of developing a hull-plate moving robot has been rising. This paper describes a hull-plate moving robot, using magnet modules as the adhesive method. Magnet modules maintain the magnetic force between hull-plate and magnets constantly. So that allows the robot to perform movements on the curved plate without the loss of adhesive force. The robot consists of driving motors, control system and magnet modules. The performance of the robot is verified on the curved plate.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.902-906
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• 2008

The linear motors are easily affected by load disturbance, force ripple, friction, and parameter variations because there is no mechanical transmission to reduce the effects of model uncertainties and external disturbance. For highspeed/high-accuracy position control of a linear-motor-driven two axes, a nonlinear adaptive controller including a cross-coupling algorithm is designed in this paper. The nonlinear effects such as friction and force ripple are estimated and compensated. An enhanced approach for cross-coupling algorithm is proposed to effectively improve the biaxial contour accuracy with the closed-loop stability. The proposed controller is evaluated through the computer simulations.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1132-1135
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• 2008

The sludge grown up in steam generators of nuclear power plants shortens the life-cycle of steam generators and reduces the output of power plants. So KHNP(Korea Hydro and Nuclear Power), the only nuclear power utility in Korea, removes it periodically using a steam generator lancing system during the outage of plants for an overhaul. KEPRI(Korea Electric Power Research Institute) has developed lancing systems with high pressured water nozzle for steam generators of nuclear power plants since 2001. In this paper, the design of a partial inter-tube lancing system for model F type steam generators will be described. The system is actuated without a DC motor inner steam generators because the motors in a steam generator make a trouble from high intensity of radioactivity as a break down.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.193-196
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• 2001

본 연구에서는 원활한 정재파 생성과 양방향 구동이 가능한 새로운 형태의 초음파 리니어 모터를 제작하고, 그 특성을 평가하였다 본 연구에서 제안한 모터는 $\lambda/4$ 간격으로 이빨 구조를 가지는 스테이터의 상, 하부에 압전소자를 $90^\circ$ 의 위치 위상차를 갖도록 부착한 형태의, 상, 하부 압전소자에 각각 동위상, 180도의 시간 위상차를 가지는 교류 전압을 인가함으로써 양방향 구동이 가능하도록 하였다. 또한 원활한 정재파를 생성할 수 있는 최적의 구조를 결정하기 위해, 여러 가지 형태의 경계조건들에 대해 유한요소해석법을 이용하여 모델링하여 각 이빨들의 변위를 관찰함으로써 각각의 구조에 대해 타당성을 검증하였다. 위 결과를 바탕으로 세 종류의 초음파 리니어 모터를 제작하여 구동실험을 하였고, 실험 결과에 따라 속도와 추력 및 양방항성이 가장 우수한 최적의 구조를 결정하였다. 본 연구에서 제작한 모터는 최대 82.4cm/s의 속도와 0.46N의 추력을 가졌다.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.825-830
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• 2001

Many techniques have been developed to evaluate the structural integrity for the traction motor with squirrel cage. However, the former approaches are not appropriate to our problems and there is no reliable specification for evaluation of squirrel cage motor. In this study, an improved boundary condition and the criteria for evaluation are proposed. Using 3-dimensional solid element, finite element model is generated. The number of meshes can be reduced by considering the symmetry of geometry. Stress analyses are carried out for three types of traction motors.