• 제어로봇시스템학회논문지
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• 제20권9호
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• pp.914-921
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• 2014

In this paper, an algorithm is suggested to detect an offset angle of the absolute rotor position sensor after the initial assembly of a PMSG. Unlike previous studies in a stationary state, this one is not designed to detect an electrical angle but rather the absolute position of the rotor is detected while operating the generator. Also,a position sensor, current sensors and voltage sensor were used to ensure reliability. This technique completes the detection of the sensor offset in two steps. In the first step, a zero-crossing of the EMF is measured using a voltage sensor to detect the electrical angle offset when the alternator is actuated by the engine. In the second step, a high frequency current is injected along the d-axis on-line during the control of the generation, eventually to obtain the inductance using a DFT (Discrete Fourier Transform), and then to ultimately extract the final electrical angle offset through the comparison of the inductance magnitude. The suggested algorithm was validated with PSIM simulation and, furthermore, was tested with actual experiments on a dynamometer.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 제5회 압연심포지엄 신 시장 개척을 위한 압연기술
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• pp.126-133
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• 2004

Lots of researches and applications on the automated overhead cranes in shops have been done for some decades, but a few successful results are reported. Integrated crane control systems designed by famous engineering companies are still expensive and are not satisfactory in view of maintenance and reliability. A more reasonable control system fit to requirements of manufacturing industries is suggested in the study. The new deigned system has superior capabilities for anti-sway of rope and position control. The controller for automated operations is composed of a Linux-based PC for non real-time control and a high-speed PLC for hard real-time control. Some algorithms required for coil yard operations as well as main control algorithms such as reference position generation, position control and anti-sway control have been designed and fully tested on the new crane simulator. The designed crane control system showed satisfactory performance on position control accuracy and anti-sway of rope. The maximum positional error is 8mm and the maximum sway error is 0.1 degrees. The suggested control strategies have been successfully applied to the 10-1 crane in No. 4 CGL of in the Kwangyang Steel Works and in commercial operation.

• 한국멀티미디어학회논문지
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• 제13권3호
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• pp.400-409
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• 2010

본 논문에서는 반도체 생산 공정 중 클리닝 공정 설비에서, 웨이퍼의 장착 위치를 인식하는 영상 인식 시스템을 제안한다. 제안한 시스템은 웨이퍼의 위치 이탈에 따른 위치오차 발생 시 이를 클리닝 설비에 전달하여, 웨이퍼 클리닝 장비의 파손을 방지하여 시스템의 신뢰성과 경제성을 높이기 위한 것이다. 시스템의 주요 알고리즘은 카메라에 획득된 영상과 실제 웨이퍼간의 캘리브레이션 방법, 적외선 조명 및 필터 설계, 최소자승법 기반의 원 생성알고리즘에 의한 중심위치 판별법이다. 제안한 시스템은 고 신뢰성과 고 정밀의 위치인식 알고리즘을 사용하여, 효율적으로 웨이퍼 인라인 공정에 설치함을 목표로 하며 실험결과 충분한 허용 기준 내에서 오차를 검출해내는 좋은 성능을 보여준다.

• Physical Therapy Rehabilitation Science
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• 제6권3호
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• pp.152-157
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• 2017

Objective: The aim of this study was to determine the intra-rater and inter-rater reliability of the dual rehabilitative ultrasound imaging (D-RUSI) when simultaneously measuring muscle thickness changes at rest and during co-contraction of the biceps brachii (BB) and triceps brachii (TB). Design: Cross-sectional study. Methods: This study included 36 healthy participants (23 men, 13 women). The participants sat on a chair in a comfortable position with a cushion placed under their elbow to maintain a 90-degree elbow flexion angle. The muscle thickness of the biceps brachii and triceps brachii was measured twice using the D-RUSI by two examiners during resting and co-contraction states. One week later, the same procedure was performed once again. Results: The intra-class correlation coefficients (ICCs) for intra-rater reliability ranged from 0.887 to 0.989 and the confidence interval was within an acceptable range of 0.778 to 0.994. The standard error of measurement (SEM) values ranged from 0.303 to 0.866 and the minimal detectable change (MDC) values ranged from 0.84 to 2.40. The ICCs for inter-rater reliability ranged from 0.758 to 0.925. The SEM values ranged from 0.702 to 1.486 and the MDC values ranged from 1.95 to 4.12. Conclusions: The use of the D-RUSI of the BB muscle had a very good intra-rater reliability and very good inter-rater reliability at the resting state, and a, good inter-rater reliability at the co-activation state. ICC values showed very good intra-reliability and inter-reliability for the TB muscle. the D-RUSI is a useful tool for simultaneously measuring the thickness of two muscles when the BB is an agonist and the TB is an antagonist during co-activation of the upper arm.

• 대한기계학회논문집
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• 제18권9호
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• pp.2257-2264
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• 1994

A method to evaluate the position performance for a stochastically defined planar robot manipulator is presented. Performance is defined as the operational reliability based upon the positional errors of the manipulator tip. An analytical method is developed and applied to a two-link robot manipulator through forward kinematics. This study includes uncertainties in the link length, pin center location and radial clearance. By virtue of the effective link length model, only the nominal manipulator model and statistical information on the uncertainties are required. The results from the analytical method is compared to those from the Monte Carlo simulation.

• International Journal of Railway
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• 제2권1호
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• pp.8-17
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• 2009

The wheelset, its functions and position under the train is the prime safety-critical component. Whether in design, qualification, manufacturing or maintenance, the wheels and axles have been the focus of special attention at SNCF for over 25 years and the French Railways are actively involved in various Research and Development work towards interoperability between the railways, railway reliability and running safety.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.251-253
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• 2006

Speed and torque controls of permanent magnet synchronous motors are usually attained by the application of position and speed sensors. However, speed and position sensors require the additional mounting space, reduce the reliability in harsh environments and increase the cost of a motor. Therefore, many studies have been performed for the elimination of speed and position sensors. This paper investigates a novel sensorless control of a permanent magnet synchronous motor. The proposed control strategy utilizes the active and reactive torque control for maximizing the active torque of a sensorless PMSM. The proposed algorithm is verified through the simulation and experimentation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.160-162
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• 2006

Speed and torque controls of induction motors are usually attained by the application of position and speed sensors. However, speed and position sensors require the additional mounting space, reduce the reliability in harsh environments and increase the cost of a motor. Therefore, many studies have been performed for the elimination of speed and position sensors. This paper investigates an improved sensorless control of an induction motor. The proposed control strategy utilizes the reactive power for estimating the speed of a sensorless induction motor. The proposed algorithm is verified through the simulation and experimentation.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2000년도 전력전자학술대회 논문집
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• pp.464-467
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• 2000

In this paper we introduce the network based multi-motors control system using CAN(Controller Area Network) The traditional multi-motors control system has many problems in the view of reliability and economy because of the amount and complexity of wiring noise and maintenance problems etc, These problems are serious especially when the motor controllers are separated widely CAN is generally applied in car networking in order to reduce the complexity of the related wiring harnesses. These traditional CAN application techniques are modified to achieve the real time communication for the multi-motor control system. And also the position synchronization technique is developed and the proposed methods are verified experimentally.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.71-73
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• 2007

Speed and torque controls of induction motors are usually attained by the application of position and speed sensors. However, speed and position sensors require the additional mounting space, reduce the reliability in harsh environments and increase the cost of a motor. Therefore, many studies have been performed for the elimination of speed and position sensors. This paper investigates an improved sensorless control of an induction motor. The proposed control strategy utilizes the MRAS(Model Reference Adaptive System) for estimating the speed of a sensorless induction motor. The proposed algorithm is verified through the simulation and experimentation.