• 한국정밀공학회지
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• 제17권2호
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• pp.220-226
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• 2000

High precision step motor using Terfenol-D linear actuators is proposed and its performance is tested. Four Terfenol-D linear actuators are set up perpendicular to the rotor and saw-tooth current signals are applied on the actuators. It was found that the rotation angle is increased as the excitation current, the inertia of the rotor, and the contact force between the rotor and the push device are increased. The rotation angle per step of $0.001^{\circ}$ and blocking torque of 0.2Nm are achieved. The effect of the time delay between the excitation signals is also investigated.

• 한국산업정보학회논문지
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• 제6권2호
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• pp.74-79
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• 2001

로봇과 자동화기기에 범용으로 사용되는 Stewing Motor의 Driving을 위하여 unipolar 방식과 bipolar 방식의 Controller Circuit를 design 하였으며 특히 design시 Digital logic을 이용하여 Controller를 설계 제작하여 실험을 통해 그 응용성을 실험하였다. 또한 Motor의 효율 향상을 위하여 Motor의 Winding에 흐르는 전류를 제어하기 위하여 constant Current Limit Methode와 Constant Voltage Limit Methode를 분석하고 실재 회로 제작 시 응용하여 Motor의 효율을 향상시켰다.

• 한국정밀공학회지
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• 제27권9호
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• pp.43-51
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• 2010

Speed, accuracy and smoothness are the important properties of pan-tilt camera. In the case of a high ratio zoom lens system, low vibration characteristic is a crucial point in driving pan-tilt mechanism. In this paper, a novel micro-stepping controller with a function of reducing vibration was designed using field programmable gate arrays (FPGA) technology for high zoom ratio pan-tilt camera. The proposed variable reference current (VRC) control scheme reduces vibration decently and optimizing coil current in order to prevent the step motor from occurring missing steps. By employing VRC control scheme, the vibration in low speed could be significantly minimized. The proposed controller can also make very high speed of 378kpps micro-step driving, and increase maximum acceleration in motion profiles.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1307-1310
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• 2005

ATM is element that reliability, stability is important in relation with customer by financial agency used device. To embody high reliability and stability, reliability estimation technology development is important. When new product is developed, performance and reliability evaluation of product are essential element. In this paper, is treating contents on reliability estimation of stepping motor, BLDC motor and solenoid that is main driving source of note handling units.

• 한국공작기계학회논문집
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• 제14권3호
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• pp.23-31
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• 2005

The purpose of this study is to design a disturbance observer for a micro-stepping stage to eliminate the disturbances from cables, friction, mass unbalance of the moving part, etc. The disturbance observer is designed for air-floating X-Y precision micro-stepping X-Y stage which widely used in stepper machine or semiconductor manufacturing systems. The micro-stepping X-Y stage has a weak point of the variation of characteristics with position locations, which caused by various disturbances. In this study, it will be described that a simple and high throughput disturbance observer algorithm improves the dynamic error and settling time of the micro-stepping stage.

• 한국전자통신학회논문지
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• 제7권6호
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• pp.1413-1422
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• 2012

비선형 적응백스텝핑 제어기법은 외부 환경에 의한 여러가지 파라미터의 변동에도 불구하고 강인한 특성을 가진다. 이를 사용하여 IPMSM(Interior Permanent Magnet Synchronous Motor)의 정밀한 속도제어기를 설계하기 위해서는 빠른 제어 주기를 가져야만 한다. 하지만 속도 측정을 위한 엔코더의 분해능의 제약으로 연산주기를 빠르게 가져가지 못하고, 결국 제어기의 성능을 높이지 못하게 된다. 본 논문은 빠르고 정밀한 속도 제어기를 설계하기 위하여 비선형 적응백스텝핑 제어기법을 적용한 센서리스 속도 제어기 설계 방법을 제안한다. 제어기는 EKF(Extended Kalman Filter)를 이용하여 추정된 속도정보를 이용하여 비선형 적응백스텝핑 제어기법을 사용하는 방식으로 IPMSM의 속도 제어를 수행한다. 제안된 제어기의 성능은 PSIM을 이용한 모의 실험을 통하여 검증하였다.

• 대한전자공학회논문지
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• 제23권6호
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• pp.888-894
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• 1986

In this paper, a phase locked loop control system is designed to have high performance and stability in a 2-phase bifilar winding PM step motor. The BODE diagram analysis method is used to improve the stability and dynamic characteristic of the closed loop control system. Also, a PLL servo is used to accomplish high-precision speed and to attain smooth ness. In applying the PLL control to the step motor, a new design method is suggested to solve the control problem which occurs as a result of the limited maximum acceleration of the step motor. A simple design method is suggested without using the complicated multi-step characteirstic of the step motor in constant voltage driving. Computer simulation results agree clorelg with experiments, indicating that the PLL servo system of the step motor designed is very useful.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.981-984
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• 2004

This paper is about the development of Automatic FPC punching instrument. FPC(flexible printed circuit) is used to detect the contact position of K/B and button like a cellular phone. Depending on the quality of the printed ink and position of reference punching point to the FPC, the resistance and current are varied to the malfunctioning values. The size of reference punching point is 2mm and the above. Because the punching operation is done manually, the accuracy of the punching degree is varied with operator's condition. Recently, The punching accuracy has deteriorated severely to the 2mm punching reference hall so that assembly of the K/B has hardly done. To improve this manual punching operation to the FPC, automatic FPC punching system is introduced. Precise mechanical parts like a 5-step stepping motor and ball screw mechanism are designed and tested and low cost PC camera is used for the sake of cost down instead of using high quality vision systems for the FA. Test algorithm shows good results to the designed automatic punching system.

• 한국정밀공학회지
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• 제22권12호
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• pp.77-86
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• 2005

This paper is about the development of Automatic FPC(flexible printed circuit) punching instrument for the improvement of working condition and cost saving. FPC is used to detect the contact position of keyboard and button like a cellular phone. Depending on the quality of the printed ink and position of reference punching point to the FPC, the resistance and current are varied to the malfunctioning values. The size of reference punching point is 2mm and the above. Because the punching operation is done manually, The punching accuracy is varied with operator's condition. Recently, The punching accuracy has deteriorated severely to the 2mm punching reference hall so that assembly of the K/B has hardly done. To improve this manual punching operation to the FPC, automatic FPC punching system is introduced. Precise mechanical parts like a 5-step stepping motor and ball screw mechanism are designed and tested and low cost PC camera is used fur the sake of cost down instead of using high quality vision systems for the factory automation. Test algorithms and programs showed good results to the designed automatic punching system and led to the increasement of productivity and huge cost down to law material like FPC by avoiding bad quality.

• International Journal of Precision Engineering and Manufacturing
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• 제8권4호
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• pp.3-9
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• 2007

Existing long range piezoelectric motors with friction based transmission mechanisms are limited by the axial load capacity. To overcome this problem, a new linear piezoelectric motor using one piezoelectric actuator combined with a novel stepping mechanism is reported in this paper. To obtain both long range and fine accuracy, dual positioning control strategy consisting of coarse positioning and fine positioning is used. Coarse positioning is used for long travel range by accumulating motion steps obtained by piezoelectric actuator. This is followed by fine positioning where required accuracy is obtained by fine motion displacement of piezoelectric actuator. This prototype is able to provide resolution of 20 nanometers and withstand a maximum axial load of 300N. At maximum load condition, the positioner can move forward to a travel distance of 5mm at a maximum speed of 0.4 mm/sec. This design of nanopositioner can be used in applications for ultra precision positioning and grinding operations where high axial force capacity is required.