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    Experimental Study on Aerodynamic Deformation of Flexible Wings of an Ornithopter

    , M.Sc. Thesis Sharif University of Technology Jaberi, Pouyan (Author) ; Mazaheri, Karim (Supervisor)
    Abstract
    Flapping motions of flexible wings generate dynamic forces. These forces include aerodynamic forces and inertial forces due to angular acceleration of wing mass, that cause aeroelastic deformation of wings. In this thesis a method is presented by use of a software and some experimental test conditions to study elastic behaviors and aerodynamic forces of flexible wings. A high speed camera records motion of wings in hovering condition and then these images is processed with software to recognize deformations (such as deflection, torsion, etc.) and aerodynamic forces due to them. Afterwards aerodynamic model and deformations is combined for better modeling. Finally we can compare results with... 

    Analysis of fuselage vibration during flapping flights and solution for reduce it

    , Article 44th AIAA Aerospace Sciences Meeting 2006, Reno, NV, 9 January 2006 through 12 January 2006 ; Volume 11 , 2006 , Pages 7681-7687 ; 1563478072 (ISBN); 9781563478079 (ISBN) Vahdat, D ; Sharif University of Technology
    2006
    Abstract
    This article presents the result of an analysis to determine the distance that the fuselage of a Flapping Flyer moves up and down when the wing flap and comparison it with experiments that was done on fuselage phenomena during flight of an ornithopters and Winged animals in Wind tunnel. It is suggested that this motion may reduce the efficiency of design, whereas the tendency for fuselage motion may be largely cancelled in the bi plane configuration. The article also answers a question that has puzzled for scientist. Why bodies of winged animals don't move up and down noticeably when they flaps their wing during flight? Finally we offer one solution for reduce this unwanted motion near 50 %... 

    Modeling and Flight Controller Design of an Insect-Like Flapping Wing in Hover

    , M.Sc. Thesis Sharif University of Technology Khodabakhsh, Hamid Reza (Author) ; Banazadeh, Afshin (Supervisor)
    Abstract
    There are many applications for micro aerial vehicles (MAV) and in nature they are flying as birds and insects. It can be said that a MAV that can mimic flying capabilities of birds and insects can be used as a solution for flying in low Reynolds number regimes. It seems that Flapping Wing MAVs have better performance than fixed and rotary wings MAV in low Reynolds number regimes. So far there haven’t been many theories and methods introduced for controlling flapping wing MAVs and many researches failed to provide a convenient way for designing an effective controller. On the other hand, models presented in literature for aerodynamics, dynamics and kinematics of flapping wing are not... 

    Fuzzy-Pade' Method for Approximating the Aerodynamic Forces in Dynamic Modeling of the Flexible Flapping Wing

    , Ph.D. Dissertation Sharif University of Technology Abedinnasab, Mohammad Hossein (Author) ; Zohoor, Hassan (Supervisor)
    Abstract
    In this thesis, we have derived the exact equations of motion for flexible beams. The derived equations are compared with similar equations reported in the literature, and they demonstrate significant power in prediction of the numerical results. The model for planar beams is verified by the performed experiments on carbon fiber rods. A new highly convergent, efficient technique which is quite fast is also developed for both approximating and controlling a system, entitled as fuzzy-Pade method. We then have studied effects of the wing flexibility on enhancing the lift and trust coefficients in the flapping flight. Aerodynamic force generation due to flapping is simulated for both the... 

    Aerodynamic Optimization of Wing Shape of an Ornithopter Using Unsteady Vortex Lattice Method

    , M.Sc. Thesis Sharif University of Technology Teymouri Bakharzi, Aiub (Author) ; Mazaheri, Karim (Supervisor)
    Abstract
    At this project, at first step has been tried to solve the flow over a plate using unsteady vortex lattice method that reached to this purpose considering reference [5] and using available code at this book. And due to existent limitations of above code, has been tried to promote it to more complex three-dimensional modes. And at next step, the code has been approved using Wagner and Theodorsen theoretical methods and then the results validated with others results. Finally, after confidence of numerical results of the written code, has been studied the effect of design parameters on the Ornithopter aerodynamics parameters to can reach to final purpose that is optimum aerodynamic shape for... 

    Dynamic Simulation of the Propulsion System of a Flapping Wing Vehicle

    , M.Sc. Thesis Sharif University of Technology Beheshtkar, Negin (Author) ; Meghdari, Ali (Supervisor)
    Abstract
    Flapping wing vehicles produce aerodynamic forces through the flapping motion of their wings. A sample flapping wing mechanism is studied in this project, which propulsion system consists of a battery, a DC motor, a gearbox, a flapping mechanism and a flexible membrane wing. The purpose of this study is simulation of the whole propulsion system through identification and simulation of each sub-system. In the current research, after an introduction to the flapping wing vehicles, literature of the flapping vehicles is reviewed. By studying relevant articles, lack of a comprehensive simulation of all sub-systems is observed. So the goal of this research is obtaining an appropriate tool for... 

    Developing a Method for the Dynamic Analysis of Flexible Flapping Wing

    , M.Sc. Thesis Sharif University of Technology Jahanbin, Zahra (Author) ; Meghdari, Ali (Supervisor)
    Abstract
    Flapping is one of the most usual solutions to produce aerodynamic lift and propulsive force in natural flights, in low Reynolds number. A sample flapping wing mechanism in which propulsion system consists of a battery, two very small DC electrical motors, two gearboxes, a flapping mechanism and flexible beams as wings is studied in this project.Different methods have been proposed to derive the governing equations of motion and simulate the flapping wing system. The main disadvantage of the previous proposed works is the lack of a comprehensive dynamical analysis of the complete system including its components.Therefore, the main objective of the present research is to propose an efficient...