• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.05a
• /
• pp.162-162
• /
• 2004

위치결정 기술은 초정밀 미세 기술의 발달과 제품의 소형화, 경량화에 대한 요구가 늘어나면서 고정밀화가 가속화되어 현재는 나노미터 수준의 위치정밀도를 요구하고 있다 현재 널리 사용되어지는 표면형상 측정기인 AFM은 분해능과 정밀도는 우수하지만, 이송 스테이지의 제한으로 측정영역이 좁은 단점이 있다. 이를 극복하기 위해서 이중서보를 사용한 방식들이 많이 제안되어 왔고 단일 서보를 사용하는 방식들도 연구되고 있다. 하지만 이중서보 방식은 여러 가지 액츄에이터와 컨트롤러를 사용해야하므로 제어알고리즘과 시스템이 복잡해지는 단점을 가지고 있다.(중략)

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.22 no.2
• /
• pp.206-215
• /
• 2013

In this paper, a synchronization control technique of dual-servo motor driven press system is proposed. An independent cascade PID control technique has been applied to the conventional press system for advancement of control stability. However, it is not easy to reduce synchronous error using the independent cascade PID control technique when some different load disturbances are involved in each motor. The eccentric error of the slide caused by the problem degrade the control performance of the BDC(Bottom Dead Center). In order to achieve reduction of the synchronous error between two servo motors and accurate position control simultaneously, a new control scheme comprised with cascade PID control loop and cross-coupling loop is proposed. In simulation using Matlab SIMULINK, the AC servo system is designed. The control performance of proposed technique is compared with conventional control technique to the model of AC servo system. Also, the sub-scale model of dual-servo motor driven press system which can replicate the slide motion is constructed for experimental verification for the performance of the proposed control technique. The cross-coupling control technique reveals more precise and stable performances in the position and synchronization controls.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.8 no.8
• /
• pp.1685-1691
• /
• 2004

The objective of this study is aimed at reducing the contour error of AC Servo derives by improving the interpolation error of each axis through variable structure control system. The errors in machining process by AC Servo motor are due to many elements, such as the delay of the servo drivers, friction and the gain mismatch between x axis and y axis motors and so on. Sliding mode control system is applied to a AC servo drive as a numerical example in this paper. The experiment results which are compared with those of typical PI scheme show the validity of improvement in circular interpolation error of the system.

• Journal of Korean Electronics
• /
• v.3 no.9
• /
• pp.75-78
• /
• 1983

• The Magazine of the IEIE
• /
• v.20 no.3
• /
• pp.22-29
• /
• 1993

• 전기산업
• /
• v.8 no.1
• /
• pp.106-109
• /
• 1997

• Journal of Drive and Control
• /
• v.17 no.4
• /
• pp.176-180
• /
• 2020

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• v.9 no.1
• /
• pp.959-962
• /
• 2005

Servomotors are used as key components of automated system by performing accurate positioning, accurate speed regulation, and precise motion control in response to commands from computers and sensors. Especially linear brushless servomotors have numerous advantages over ball screws, timing belts, rack/pinion drives and friction drives compared with rotary servomotors. This paper proposes the estimation of unknown parameters from the linear brushless DC motor which is operated by sinusoidal commutation. The estimated parameters are used to tune the controller gain and disturbance observer. In order to agree with this purpose, Digital Signal Processor(TMS320F240), developed for implementation of a speed Field Oriented Control(FOC), adopted in this study. The processor playing an important role in controller has A/D converters, PWM generators, riched I/O port internally.

• Proceedings of the KIPE Conference
• /
• 2007.11a
• /
• pp.157-159
• /
• 2007

본 연구는 인코더를 사용한 Flatbed scanner DC 서보 모터시스템의 저속 제어기 설계 기법을 제안한다. 실제 구동되는 저속에서 DC 모터 시스템을 MSR 알고리즘으로 모델링하여 파라미터의 변동과 부하 외란을 추정하고, 속도 제어주기마다 위치 추종명령을 계산하여 실제 위치에 대한 에러를 보상하도록 설계함으로써 저속에서의 속도 추종능력을 향상시킨다.

• Korean Journal of Optics and Photonics
• /
• v.30 no.6
• /
• pp.243-248
• /
• 2019

The respiratory tract is an essential part of the respiratory system involved in the process of respiration. However, if stenosis occurs, it interferes with breathing and can even lead to death. Asthma is a typical example of a reversible cause of airway narrowing, and the number of patients suffering from acute exacerbation is steadily increasing. Therefore, it is important to detect airway narrowing early and prevent the patient's condition from worsening. Optical coherence tomography (OCT), which has high resolution, is suitable for observing the microstructure of tissues. In this study we developed an endoscopic OCT system. We combined a 1300-nm OCT system with a servo motor, which can rotate at a high speed. A catheter was pulled back using a linear stage while imaging with 360° rotation by the motor. The motor was selected considering various requirements, such as torque, rotational speed, and gear ratio of pulleys. An ex vivo rabbit tracheal model was used as a sample, and the sample and catheter were immobilized by acrylic structures. The OCT images provided information about the structures of the mucosa and submucosa. The difference between normal and stenosed parts in the trachea was confirmed by OCT. Furthermore, through a three-dimensional (3-D) reconstruction process, it was possible to identify and diagnose the stenosis in the 3-D image of the airway, as well as the cross-sectional image. This study would be useful not only for diagnosing airway stenosis, but also for realizing 3-D imaging.