• 한국항공우주학회지
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• 제38권4호
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• pp.327-334
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• 2010

최근 개발된 항공기는 대부분 디지털 Fly-By-Wire(FBW) 혹은 광신호를 사용하는 Fly-By-Light(FBL) 시스템을 사용하고 있다. 이러한 시스템들은 조종사의 직접 조종으로는 불가능하거나 어려운 복잡한 임무의 수행, 비행범위 확장, 신뢰성 향상 등의 장점을 가지고 있다. FBW 기술을 적용한 비행제어기술이 발전됨에 따라 운항 시 안정성 확보 및 보다 효율적인 임무수행을 위해 비행영역(Flight Envelope) 보호의 개념이 항공기 설계에 있어 중요한 문제로 부각되고 있다. 본 논문에서는 dynamic trim 알고리즘, peak response estimation, 제어이득 스케쥴링 등의 방법을 이용해서 항공기의 비행영역 보호를 수행하고, 각 방법의 성능을 비교하여 최적의 제어기를 설계하는 연구를 수행하였다.

• 한국기계가공학회지
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• 제14권5호
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• pp.42-49
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• 2015

In this study, the multi-disk of a high-pressure drop control valve is designed and manufactured. Then, the flow rate and high-pressure drop of fluids flowing in the high-pressure drop control valve is CAE/CFD. This study involves numerical analysis for the Zambil offshore project of a high-pressure drop control valve. ANSYS used a solver for offshore structures analysis. A high-pressure drop control valve, which transforms the power transfer of a system by reducing the inlet pressure of 345bar to the outlet pressure of 112bar, is a fundamental component in the offshore process. This study not only analyzes the relation between pressure drop and fluid velocity in a trim by using fluid analysis, but also examines the possibility of cavitation in a valve in addition to the plot for the extension of lifespan. It is demonstrated that the pressure drop from 345bar to 112bar is more feasible in the presence of the trim, which can induce a continuous and diminutive pressure drop in order to prevent cavitation in a high-pressure drop control valve.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.1308-1311
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• 1996

We propose a new linearized model which can be used very efficiently for the design and analysis of the autopilot of aerodynamically controlled skid-to-turn missiles. Proposed model is based on the linearized equations of the missile dynamics derived in the aerodynamic frame where xz plane contains the missile longitudinal axis and velocity vector. However, to take the effect due to the small perturbation of the missile body into consideration, we introduce a new frame which is identical to the aerodynamic frame in the trim state but after small perturbation it moves fixed with the missile body, and finally, the proposed model is set up in this frame. It is shown by nonlinear simulations and stability analysis of a numerical example that the new model describes the missile motion better than the conventional one linearized in the body frame with a certain amount of simplification.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1991년도 하계학술대회 논문집
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• pp.47-50
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• 1991

LPM(Linear Pulse Motor) provide direct and precise position control of bidirectional linear motion. LPM is not subject to the same linear velocity and acceleration limitations inherent in systems converting rotary to linear motion such as lead screws, rack and pinion, belt and pulley drives. With LPM, all the thrust force generated by the motor is efficiently applied directly to the load. And speed, distance, and acceleration are easily programmed in a highly repeatable fashion. Potential industrial and application fields of LPM include PCB assembly, industrial sewing machines, automatic inspection, coil winder, medical uses, conveyer system, laser cut and trim systems, semiconductor wafer processing, OA instruments etc. This paper describes various design parameter of LPM such as magnetic ciucuit construction methods, phase number and tooth number per pole, permanent magnet and coil mmf, tooth geometries. And to solve the problems of existing control methods, in this paper, a new control method of the LPM is proposed throughout modern control theory.

• 드라이브 ㆍ 컨트롤
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• 제10권4호
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• pp.14-21
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• 2013

The numerical analysis of the automatic ship mooring system which was equipped in the ship for trying to berth at the pier was performed in this study. The automatic ship mooring using hydraulic winch was a new method that had not need to change the existing devices and to help a pilot ship of outside. The numerical results of the proposed mooring system including ship motion were that the speed and rolling phenomenon of ship was affected by changing in the ship weight and affected the slope maintenance and yaw degree of ship if there has a trim of stern. Also, a static force of ship at the initial movement was important to calculate the mooring power. The moving force and inertial force of ship on the vertical direction was confirmed for the mooring stability. Therefore, the power and velocity of hydraulic mooring winch should be determined by considering the significant characteristics such as weight, velocity, inertial force and moving force of ship.