• 소음진동
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• 제7권6호
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• pp.967-974
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• 1997

Distributed piezoeletric sensor and actuator have been designed for efficient vibration control of a cantilevered beam. Both PZT and PVDF have been used in this study, the former as an actuator and the latter as a sensor for the integrated structure. We have optimized the position and the size of the PZT actuator and the electrode shape of the PVDF sensor. Finite element method is used to model the structure and the optimized actuators, we have designed the active electrode width of the PVDF sensor along the span of the beam. Actuator design is based on the criterion of minimizing the system energy in the control modes under a given initial condition. Model control forces for the residual (uncontrolled) modes have been minimized during the sensor design to minimize the observation spill-over. Genetic algorithm and sequential quadratic programming technique have been utilized as an optimization scheme. Discrete LQG control law has been applied to the integrated structure for real time vibration control. Performance of the sensor, the actuator, and the integrated smart structure has been demonstrated by experiments.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 추계학술대회논문집
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• pp.374-375
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• 2008

In this study, the nano-composite actuator based on Fullerene and Nafion was newly developed to improve the electro active polymer actuators. The tensile test was employed to define the mechanical stiffness and strength of the nano-composite membrane. Also, the bending displacement of the Fullerene-Nafion based nano-composite actuator was investigated under DC and AC excitations with various magnitudes and frequencies. As a result, the new nano-composite actuator based on Fullerene-Nafion shows much larger deformation than the pure Nafion based actuator and solves the straightening back Problem of the previous electro active polymer actuators.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1998년도 춘계학술대회논문집; 용평리조트 타워콘도, 21-22 May 1998
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• pp.684-688
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• 1998

Optimization of the collocated piezoceramic sensor/actuator placement is investigated numerically and verified experimentally for vibration control of laminated composite plates. The finite element method is used for the analysis of dynamic characteristics of the laminated composite plates with the piezoceramic sensor/actuator. The structural damping index(SDI) is defined from the modal damping. It is chosen as the objective function for optimization. Weights for each vibrational mode are taken into account in the SDI calculation. The gradient method is used for the optimization. Optimum location of the piezoceramic sensor/actuator is determined by maximizing tie SDI. Numerical simulation and experimental results show that the optimum location of the piezoceramic sensor/actuator is dependent upon the outer layer fiber orientations of the plate, and location and size of the piezoceramic sensor/actuator.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.284-287
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• 2001

This paper presents the robust control simulation of a composite beam using self-sensing actuators(SSA). The self-sensing actuator is a new concept for intelligent material, where a single piezoelectric element simultaneously functions as both a sensor and an actuator. In a practical implementation of the self-sensing actuator an electrical bridge circuit is used to measure strain. The circuit could provide significant information about strain in the element if it were well-balanced. Our aim is design a robust controller which guarantees that the performance of a self-sensing actuator is robust against perturbation of the bridge balance and to confirm the advantages of this technique. Simulation results show that the self-sensing actuator driven by the designed controller exhibits excellent performance in suppressing the vibration of a composite beam.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 추계학술대회 논문집
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• pp.173-174
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• 2007

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국내학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
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• pp.27-31
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• 1988

A study has been carried out on the implementation of IMCA (Linear Moving Voice Coil Actuator) to a flexible robot arm modelled as cantilever beam. Control performances are evaluated by computer simulation and theoretical analysis is validated by experiments. From this study, it is proved that the LMVCA can be applied easily to the control system and suppress vibration effectively.

• 한국항행학회논문지
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• 제13권6호
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• pp.813-819
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• 2009

무인항공기의 에일러론 및 플랩, 엘리베이터 등을 제어하기위한 작동기들은 구조적으로 Time variant한 비선형적인 특성을 가지고 있을 뿐 아니라, 비행 중에 풍향 및 풍량에 따라 모델링하기 힘든 외란이 발생할 경우가 많이 발생하기 때문에 우수한 제어성능을 보이는 제어기 설계에 많은 어려움이 있었다. 본 논문에서는 기존의 PID 제어기의 장점을 그대로 살리면서 실시간으로 변화하는 시스템에 adaptive하게 대응할 수 있고 Auto gain tuning을 이용하여 개발자의 시간과 노력을 현저히 줄일 수 있는 Fuzzy Auto gain tuning PID 제어 알고리즘을 비행체 Actuator 제어에 적용한 연구내용을 기술하였다.

• Composites Research
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• 제19권5호
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• pp.7-11
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• 2006

SWNT(Single-Walled Carbon Nanotubes)와 도전성 고분자 PANi(Polyaniline)로 구성된 복합재료 합성물질을 제조하여 전기적 기계적 특성을 실험적으로 조사하였다. 이러한 재료는 인공근육 등으로 사용될 수 있어서 미소 인공생물체및 로봇의 구동에 응용될 수 있다. 이 작동기는 90% 순도의 SWNT와 화학적 Polymerization을 이용하여 본 연구실에서 개발된 완전히 새로운 방식으로 제조되었다. 4 탐침 측정법(4-probe method)을 사용하여 이 필름형 복합재 작동기의 전기전도도를 측정한 결과 56.15 S/cm의 값을 나타냈으며, 순수 PANi은 17.38 S/cm를 나타내었다. 순수한 도전성 폴리머 보다 3.2배 높은 전도성을 나타내었다. 이 작동기의 재료적 특성은 SEM을 사용하여 분석하였으며, 우수한 특성을 갖고 있었다. 전압이 작용할 때 변형률을 측정하기 위해서 레이저 측정 센서가 부착된 측정장치가 개발되었으며, $NaNO_3$ 용액 속에서 작동되며, 1볼트의 전압이 가해졌다. 초기 길이 12.690 mm에서 12.733 mm로 늘어났으며, 0.34%의 변형률이 계산되었다. 이 값은 호주 Tahhan의 0.23%보다 48% 정도 높은 변형률이다.

• 드라이브 ㆍ 컨트롤
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• 제8권3호
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• pp.53-58
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• 2011

• 한국소음진동공학회논문집
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• 제12권4호
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• pp.294-301
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• 2002

Vibration control of a plate using an optical fiber sensor and a piezoelectric actuator is considered in the present study, An aluminum plate with attached Extrinsic Fabry-Perot Interferometer (EFPI) and piezoelectric actuator is prepared for experimental investigation. Vibration level of EFPI that can represent the mechanical strain without severe distortion Is validated by forced nitration experiment. A linear time invariant system model is constructed based on the experimentally obtained frequency responses, and an optimal controller is designed for the multi-modal vibration suppression. Control performance is presented in frequency and time domains. It is found that the nitration level of the first three modes can be greatly reduced. The effect of low-pass filtering used to eliminate high frequency noise on the stability and control performance is also considered.