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Modeling and Design of H-Infinity Controller for Piezoelectric Actuator LIPCA

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Journal of Bionic Engineering 2010年第2期7卷 168-174页

作者： Gigun Lee Kwanwoo You Taesam Kang kwang joon yoon Jeong Oog Lee Jung Keun Park Department of Aerospace Information Engineering Konkuk University

We proposed a dynamic model identification and design of an H-Infinity （i.e.H） controller using a LightweightPiezo-Composite Actuator （LIPCA）.A second-order dynamic model was obtained by using input and output data, and applyingan identification *** identified model coincides well with the real *** reduce the resonating mode that istypical of piezoelectric actuators, a notch filter was used.A feedback controller using the Hcontrol scheme was designed basedon the identified dynamic model; thus, the LIPCA can be easily used as an actuator for biomemetic applications such as artificialmuscles or macro/micro positioning in *** control algorithm was implemented using a microprocessor, analogfilters, and power amplifying *** simulation and experimental results demonstrate that the proposed control algorithmworks well in real environment, providing robust performance and stability with uncertain disturbances.

关键词： piezoelectric actuator model identification H-infinity controller biomimetic artificial muscle LIPCA

Non-Jumping Take off Performance in Beetle Flight （Rhinoceros Beetle Trypoxylus dichotomus）

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Journal of Bionic Engineering 2014年第1期11卷 61-71页

作者： Tien Van Truong Tuyen Quang Le Hoon Cheol Park kwang joon yoon Min Jun Kim Doyoung Byun Department of Aerospace and Information Engineering Konkuk University Seoul South Korea Department of Mechanical Engineering National University of Singapore Singapore KoreaInstitute of Ocean Science and Technology PO Box 29 Ansan 425-600 South Korea Department of Advanced Technology Fusion Konkuk University Seoul South Korea Department of Mechanical Engineering and Mechanics Drexel University Philadelphia PA 19104 USA Department of Mechanical Engineering Sungkyunkwan University Suwon South Korea

In recent decades, the take-off mechanisms of flying animals have received much attention in insect flight initiation. Most of previous works have focused on the jumping mechanism, which is the most common take-off mechanism found in flying animals. Here, we presented that the rhinoceros beetle, Trypoxylus dichotomus, takes offwithout jumping. In this study, we used 3-Dimensional （3D） high-speed video techniques to quantitatively analyze the wings and body kinematics during the initiation periods of flight. The details of the flapping angle, angle of attack of the wings and the roll, pitch and yaw angles of the body were investigated to understand the mechanism of take-off in T. dichotomus. The beetle took off gradually with a small velocity and small acceleration. The body kinematic analyses showed that the beetle exhibited stable take-off. To generate high lift force, the beetle modulated its hind wing to control the angle of attack; the angle of attack was large during the upstroke and small during the downstroke. The legs of beetle did not contract and strongly release like other insects. The hind wing could be con- sidered as a main source of lift for heavy beetle.

关键词： take-oft non-jumping mechanism rhinoceros beetle kinematics

Flow Visualization of Rhinoceros Beetle （Trypoxylus dichotomus） in Free Flight

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Journal of Bionic Engineering 2012年第3期9卷 304-314页

作者： Tien Van Truong Tuyen Quang Le Hieu Trung Tran Hoon Cheol Parka kwang joon yoon Doyoung Byun . Department of Aerospace Information Engineering Konkuk University Seoul 143-70 l Republic of Korea 2.Costal Engineering and Ocean Energy Research Department Korea Ocean Research and Development Institute 454 Haeanro Sangrok-gu Ansan 426-744 Republic of Korea Department of Advanced Technology Fusion Konkuk University Seoul 143-701 Republic of Korea Department of Mechanical Engineering Sungkyunkwan University Suwon 440-746 Republic of Korea

Aerodynamic characteristics of the beetle, Trypoxylus dichotomus, which has a pair of elytra （forewings） and flexible hind wings, are investigated. Visualization experiments were conducted for various flight conditions of a beetle, Trypoxylus di- chotomus： free, tethered, hovering, forward and climbing flights. Leading edge, trailing edge and tip vortices on both wings were observed clearly. The leading edge vortex was stable and remained on the top surface of the elytron for a wide interval during the downstroke of free forward flight. Hence, the elytron may have a considerable role in lift force generation of the beetle. In addition, we reveal a suction phenomenon between the gaps of the hind wing and the elytron in upstroke that may improve the positive lift force on the hind wing. We also found the reverse clap-fling mechanism of the T. dichotomus beetle in hovering flight. The hind wings touch together at the beginning of the upstroke. The vortex generation, shedding and interaction give a better understanding of the detailed aerodynamic mechanism of beetle flight.

关键词： beetle smoke wire visualization free flight hovering flight wing interaction elytron effect

Mimicking a Superhydrophobic Insect Wing by Argon and Oxygen Ion Beam Treatment on Polytetrafluoroethylene Film

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Journal of Bionic Engineering 2009年第4期6卷 365-370页

作者： Youngjong Lee Yonghoon Yoo Jihoon Kim Sriyulianti Widhiarini Baeho Park Hoon Cheol Park kwang joon yoon Doyoung Byun Department of Aerospace Information Engineering Konkuk UniversitySeoul 143-701Republic of Korea Department of Physics Konkuk UniversitySeoul 143-701Republic of Korea Department of Advanced Technology Fusion Konkuk UniversitySeoul 143-701Republic of Korea

Biological tiny structures have been observed on many kinds of surfaces such as lotus leaves and insect wings,which enhance the hydrophobicity of the natural surfaces and play a role of *** presented the fabrication technology of a superhydrophobic surface using high energy ion *** insect wings that mimic the morphology and the superhydrophobocity of cicada's wings were successfully fabricated using argon and oxygen ion beam treatment on a polytetrafluoroethylene (PTFE)*** wing structures were supported by carbon/epoxy fibers as artificial flexible veins that were bonded through an autoclave *** morphology of the fabricated surface bears a strong resemblance to the wing surface of a cicada,with contact angles greater than 160°,which could be sustained for more than two months.

关键词： superhydrophobic insect wing mimicry of the wing ion beam treatment artificial flapper dynamic contact angle

Bird-mimetic Wing System of Flapping-wing Micro Air Vehicle with Autonomous Flight Control Capability

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Journal of Bionic Engineering 2016年第3期13卷 458-467页

作者： Sriyulianti Widhiarini Ji Hwan Park Bum Soo yoon kwang joon yoon ll-Hyun Paik Jong Heon Kim Chan Yik Park Seung Moon Jun Changho Nam Department of Aerospace Engineering Konkuk University Gwangjin-gu Seoul South Korea Deptartment of PGM Technology Hanwha Corp. R&D Center Daejeon South Korea Agency for Defense Development Daejeon South Korea Department of Engineering Technology Arizona State University Mesa Arizona

A micro air vehicle with a bird-mimetic up-down and twisting wing drive system was developed in this study. The Flap- ping-wing Micro Air Vehicle （FMAV）, with a 50 cm wingspan and a double-crank drive system, performed successful flights of up to 23 min. The performance and capabilities of the FMAV were enhanced by adapting a number of unique features, such as a bird-mimetic wing shape with a span-wise camber and an up-down and twisting wing drive mechanism with double-crank linkages, This lift-enhancing design by mimicking the flapping mechanism of a bird＇s wing enabled the 210 g FMAV to fly autonomously in an outdoor field under wind speeds of less than 5 m.s-1. Autonomous flight was enabled by installing a flight control computer with a micro-electro-mechanical gyroscope and accelerometers, along with a micro video camera and an ultralight wireless communication system inside the fuselage. A comprehensive wind tunnel test shows that the FMAV with a high-camber wing and double-crank mechanism generates more lift and less net thrust than the FMAV with a flat wing and single-crank mechanism, which confirms the improved performance of the developed FMAV, as well as the superior slow flying or hovering capabilities of the FMAV with a high-camber wing and double-crank wing drive system.

关键词： flapping-wing MAV autonomous flight biomimetic wing double crank wing

Two- and Three-Dimensional Simulations of Beetle Hind Wing Flapping during Free Forward Flight

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Journal of Bionic Engineering 2013年第3期10卷 316-328页

作者： Tuyen Quang Le Tien Van Truong Hieu Trung Tran Soo Hyung Park Jin Hwan Ko Hoon Cheol Park kwang joon yoon Doyoung Byun Korea Institute of Ocean Science and Technology PO Box 29 Ansan 425-600 Republic of Korea Department of Aerospace and Information Engineering Konkuk University Seoul Republic of Korea Department of Advanced Technology Fusion Konkuk University Seoul Republic of Korea Department of Mechanical Engineering Sungkyunkwan University Suwon440-746 Republic of Korea

Aerodynamic characteristic of the beetle, Trypoxylus dichotornus, which has a pair of elytra （forewings） and hind wings, is numerically investigated. Based on the experimental results of wing kinematics, two-dimensional （2D） and three-dimensional （3D） computational fluid dynamic simulations were carried out to reveal aerodynamic performance of the hind wing. The roles of the spiral Leading Edge Vortex （LEV） and the spanwise flow were clarified by comparing 2D and 3D simulations. Mainly due to pitching down of chord line during downstroke in highly inclined stroke plane, relatively high averaged thrust was produced in the free forward flight of the beetle. The effects of the local corrugation and the camber variation were also investigated for the beetle＇s hind wings. Our results show that the camber variation plays a significant role in improving both lift and thrust in the flapping. On the other hand, the local corrugation pattern has no significant effect on the aerodynamic force due to large angle of attack during flapping.

关键词： beetle flight forward flight three-dimensional simulation corrugation effect time-camber variation

Temperature Distribution and Thermal Stresses in Various Conditions of Moving Heating Source during Line Heating Process

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Journal of Thermal Science 2012年第1期21卷 82-87页

作者： yoon Hwan Choi Yeon Won Lee kwang Choi Deog Hee Doh Kyoung joon Kim Department of Mechanical and Automotive Engineering Pukyong National University Steel Structure Research Division Research Institute of Industrial Science & Technology Division of Mechanical and information Engineering Korea Maritime University

Line heating method is widely used to manufacture curved surfaces in ship building. The main factors governing the quality of the manufactured products are the moving velocity of the heating source, heating strength, and heating ways. In this study, the temperature distributions of the heated plate were investigated with the condition that the line heating process was automatic. The temperature variations were also investigated with the changes of those three variables. The numerical results showed that the peak temperature decreased as the moving velocity of the heating source increased. It also revealed that the peak temperatures changed linearly with the changes of the heating source.

关键词： Moving heat source Line heating Thermal stress Residual deformation Conductive heat transfer

A THREE-PARAMETER FAULT-DETECTION SOFTWARE RELIABILITY MODEL WITH THE UNCERTAINTY OF OPERATING ENVIRONMENTS

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Journal of Systems Science and Systems Engineering 2017年第1期26卷 121-132页

作者： kwang yoon Song In Hong Chang Hoang Pham Department of Computer Science and Statistics Chosun University Gwangju 62022 Korea Department of Industrial and Systems Engineering Rutgers University NJ 08855-8018 USA

As requirements for system quality have increased, the need for high system reliability is also increasing. Soflnvare systems are extremely important, in terms of enhanced reliability and stability, for providing high quality services to customers. However, because of the complexity of software systems, soft-ware development can be time-consuming and expensive. Many statistical models have been developed in the past years to estimate soflnvare reliability. In this paper, we propose a new three-parameter fault-detection software reliability model with the uncertainty of operating environments. The explicit mean value function solution for the proposed model is presented. Examples are presented to illustrate the goodness-of-fit of the proposed model and several existing non-homogeneous Poisson process （NHPP） models based on three sets of failure data collected from software applications. The results show that the proposed model fits significantly better than other existing NHPP models based on three criteria such as mean squared error （MSE）, predictive ratio risk （PRR）, and predictive power （PP）.

关键词： Nonhomogeneous Poisson process ratio risk predictive power fault detection software reliability mean squared error predictive

Uncertainty analysis of flow rate measurement for multiphase flow using CFD

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Acta Mechanica Sinica 2015年第5期31卷 698-707页

作者： joon-Hyung Kim Uk-Hee Jung Sung Kim joon-Yong yoon Young-Seok Choi Department of Mechanical Design Engineering Hanyang University Thermal & Fluid System R&BD Group Korea Institute of Industrial Technology Energy System Engineering University of Science and Technology

The venturi meter has an advantage in its use,because it can measure flow without being much affected by the type of the measured fluid or flow ***,it has excellent versatility and is being widely applied in many *** flow of a liquid containing air is a representative example of a multiphase flow and exhibits complex flow *** particular,the greater the gas volume fraction（GVF）,the more inhomogeneous the flow *** a result,using a venturi meter to measure the rate of a flow that has a high GVF generates an *** this study,the cause of the error occurred in measuring the flow rate for the multiphase flow when using the venturi meter for analysis by *** ensure the reliability of this study,the accuracy of the multiphase flow models for numerical analysis was verified through comparison between the calculated results of numerical analysis and the experimental *** a result,the Grace model,which is a multiphase flow model established by an experiment with water and air,was confirmed to have the highest ***,the characteristics of the internal flow Held about the multiphase flow analysis result generated by applying the Grace model were analyzed to find the cause of the uncertainty occurring when measuring the flow rate of the multiphase flow using the venturi meter.A phase separation phenomenon occurred due to a density difference of water and air inside the venturi,and flow inhomogeneity happened according to the flow velocity difference of each *** was confirmed that this flow inhomogeneity increased as the GVF increased due to the uncertainty of the flow measurement.

关键词： Multiphase flow Measurement Numerical analysis Venturi meter Gas volume fraction(GVF) Uncertainty Multiphase flow model Grace model