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1
George, Ryan Brandon. "Design and Analysis of a Flapping Wing Mechanism for Optimization." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2737.
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Furthering our understanding of the physics of flapping flight has the potential to benefit the field of micro air vehicles. Advancements in micro air vehicles can benefit applications such as surveillance, reconnaissance, and search and rescue. In this research, flapping kinematics of a ladybug was explored using a direct linear transformation. A flapping mechanism design is presented that was capable of executing ladybug or other species-specific kinematics. The mechanism was based on a differential gear design, had two wings, and could flap in harsh environments. This mechanism served as a test bed for force analysis and optimization studies. The first study was based on a Box-Behnken screening design to explore wing kinematic parameter design space and manually search in the direction of flapping kinematics that optimized the objective of maximum combined lift and thrust. The second study used a Box-Behnken screening design to build a response surface. Using gradient-based techniques, this surface was optimized for maximum combined lift and thrust. Box-Behnken design coupled with response surface methodology was an efficient method for exploring the mechanism force response. Both methods for optimization were capable of successfully improving lift and thrust force outputs. The incorporation of the results of these studies will aid in the design of more efficient micro air vehicles and with the ultimate goal of leading to a better understanding of flapping wing aerodynamics and the development of aerodynamic models.
2
Naegle, Nathaniel Stephen. "Force Optimization and Flow Field Characterization from a Flapping Wing Mechanism." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3278.
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Flapping flight shows promise for micro air vehicle design because flapping wings provide superior aerodynamic performance than that of fixed wings and rotors at low Reynolds numbers. In these flight regimes, unsteady effects become increasingly important. This thesis explores some of the unsteady effects that provide additional lift to flapping wings through an experiment-based optimization of the kinematics of a flapping wing mechanism in a water tunnel. The mechanism wings and flow environment were scaled to simulate the flight of the hawkmoth (Manduca sexta) at hovering or near-hovering speeds. The optimization was repeated using rigid and flexible wings to evaluate the impact that wing flexibility has on aerodynamic performance of flapping wings. The trajectories that produced the highest lift were compared using particle image velocimetry to characterize the flow features produced during the periods of peak lift. A leading edge vortex was observed with all of the flapping trajectories and both wing types, the strength of which corresponded to the measured amount of lift of the wing. This research furthers our understanding of the lift-generating mechanisms used in nature and can be applied to improve the design of micro air vehicles.
3
Conn, Andrew T. "Development of novel flapping mechanism technologies for insect-inspired micro air vehicles." Thesis, University of Bristol, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492441.
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Insect-inspired micro air vehicles (MAVs) have the capacity for higher lift forces and greater manoeuvrability at low flight speeds compared to conventional flight platforms, making them suitable for novel indoor flight applications. This thesis presents development studies of an actuated flapping mechanism for an insect-inspired MAV. An original theoretical understanding has shown that the kinematical constraint of a flapping mechanism fundamentally determines its complexity and performance. An under-constrained mechanism is optimal but almost always requires a linear input. A power optimisation study has demonstrated that the only technologically mature actuation devices with viable power densities for flight are rotary. Consequently, previous airborne flapping MAVs utilised constrained rotary-input mechanisms which require conventional control surfaces that significantly reduce flight manoeuvrability.
4
DiLeo, Christopher. "Development of a tandem-wing flapping micro aerial vehicle prototype and experimental mechanism." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 154 p, 2007. http://proquest.umi.com/pqdweb?did=1421622011&sid=3&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Kummari, Kranti Kiran Lal. "The development of piezoelectric actuated mechanism for flapping wing micro aerial vehicle application." Thesis, Cranfield University, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.515094.
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Jadhav, Gautam. "The Development of a Miniature Flexible Flapping Wing Mechanism for use in a Robotic Air Vehicle." Thesis, Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14594.
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In this study a mechanism which produced flapping and pitching motions was designed and fabricated. These motions were produced by using a single electric motor and by exploiting flexible structures. The aerodynamic forces generated by flexible membrane wings were measured using a two degree of freedom force balance. This force balance measured the aerodynamic forces of lift and thrust. Two sets of wings with varying flexibility were made. Lift and thrust measurements were acquired as the mechanism flapped the wings in a total of thirteen cases. These thirteen cases consisted of zero velocity free stream conditions as well as forward flight conditions of five meters per second. In addition, flapping frequency was varied from two Hertz to four Hertz, while angle of attack offsets varied from zero degrees to fifteen degrees. The four most interesting conditions for both sets of wings were explored in more detail. For each of these conditions, high-speed video of the flapping wing was taken. The images from the video were also correlated with cycle averaged aerodynamic forces produced by the mechanism. Several observations were made regarding the behavior of flexible flapping wings that should aid in the design of future flexible flapping wing vehicles.
7
Fader, John. "Study of a novel, four degree-of-freedom spatial flapping mechanism for air vehicles." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 91 p, 2009. http://proquest.umi.com/pqdweb?did=1654487461&sid=3&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Karasek, Matej. "Robotic hummingbird: design of a control mechanism for a hovering flapping wing micro air vehicle." Doctoral thesis, Universite Libre de Bruxelles, 2014. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209177.
Full textAbstract:
The use of drones, also called unmanned aerial vehicles (UAVs), is increasing every day. These aircraft are piloted either remotely by a human pilot or completely autonomously by an on-board computer. UAVs are typically equipped with a video camera providing a live video feed to the operator. While they were originally developed mainly for military purposes, many civil applications start to emerge as they become more affordable.
Micro air vehicles are a subgroup of UAVs with a size and weight limitation; many are designed also for indoor use. Designs with rotary wings are generally preferred over fixed wings as they can take off vertically and operate at low speeds or even hover. At small scales, designs with flapping wings are being explored to try to mimic the exceptional flight capabilities of birds and insects.
The objective of this thesis is to develop a control mechanism for a robotic hummingbird, a bio-inspired tail-less hovering flapping wing MAV. The mechanism should generate moments necessary for flight stabilization and steering by an independent control of flapping motion of each wing.
The theoretical part of this work uses a quasi-steady modelling approach to approximate the flapping wing aerodynamics. The model is linearised and further reduced to study the flight stability near hovering, identify the wing motion parameters suitable for control and finally design a flight controller. Validity of this approach is demonstrated by simulations with the original, non-linear mathematical model.
A robotic hummingbird prototype is developed in the second, practical part. Details are given on the flapping linkage mechanism and wing design, together with tests performed on a custom built force balance and with a high speed camera. Finally, two possible control mechanisms are proposed: the first one is based on wing twist modulation via wing root bars flexing; the second modulates the flapping amplitude and offset via flapping mechanism joint displacements. The performance of the control mechanism prototypes is demonstrated experimentally.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished
9
Ryan, Mark. "Design Optimization and Classification of Compliant Mechanisms for Flapping Wing Micro Air Vehicles." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1345403446.
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Liu, Teresa (Teresa H. ). "Design of a flapping mechanism for reproducing the motions at the base of a dragonfly wing." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/40456.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.Includes bibliographical references (p. 48-49).
Insect flight is being studied to aid in the development of micro-air vehicles that use the flapping wing model in an attempt to achieve the high levels of maneuverability that insects have. The flight of the dragonfly has been chosen to be modeled because of its exceptional flight capabilities. This thesis addresses the flapping mechanism designed for the root of each wing. The prototype of the mechanism, built at a scale of four times the size of a dragonfly having a wingspan of 150 mm, is able to create motions in the wing of flapping and feathering, and can vary the stroke plane. The coning angle can be set between tests. The design process began with considering two methods of actuation, a four-bar transmission mechanism used in the Micromechanical Flying Insect developed in the UC Berkeley Biomimetic Millisystem Lab, and by pivoting the wing support directly with cables or rigid links. The second design was chosen to be developed further. A functional prototype was built from acrylic and parts made using stereolithography.
by Teresa Liu.
S.B.
11
Wilcox, Michael Schnebly. "Trajectory Generation and Optimization for Experimental Investigation of Flapping Flight." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/3953.
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Though still in relative infancy, the field of flapping flight has potential to have a far-reaching impact on human life. Nature presents a myriad of examples of successful uses of this locomotion. Human efforts in flapping flight have seen substantial improvement in recent times. Wing kinematics are a key aspect of this study. This study summarizes previous wing trajectory generators and presents a new trajectory generation method built upon previous methods. This includes a novel means of commanding unequal half-stroke durations subject to robotic trajectory continuity requirements. Additionally, previous optimization methods are improved upon. Experimental optimization is performed using the new trajectory generation method and a more traditional means. Methods for quantifying and compensating for sensor time-dependence are also discussed. Results show that the Polar Fourier Series trajectory generator advanced rapidly through the optimization process, especially during the initial phase of experimentation. The Modified Berman and Wang trajectory generator moved through the design space more slowly due to the increased number of kinematic parameters. When optimizing lift only, the trajectory generators produced similar results and kinematic forms. The findings suggest that the objective statement should be modified to reward efficiency while maintaining a certain amount of lift. It is expected that the difference between the capabilities of the two trajectory generators will become more apparent under such conditions.
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McIntosh, Sean Harold. "Design and analysis of a mechanism creating biaxial wing rotation for applications in flapping-wing air vehicles." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 2.97 Mb., 120 p, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:1430778.
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Moses, Kenneth C. "Biomimicry of the Hawk Moth, Manduca sexta (L.): Forewing and Thorax Emulation for Flapping-Wing Micro Aerial Vehicle Development." Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case158687503705972.
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Cheng, Bo. "Passive rotational damping in flapping flight." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 89 p, 2009. http://proquest.umi.com/pqdweb?did=1889090361&sid=9&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Dadashi, Shirin. "Modeling and Approximation of Nonlinear Dynamics of Flapping Flight." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/78224.
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The first and most imperative step when designing a biologically inspired robot is to identify the underlying mechanics of the system or animal of interest. It is most common, perhaps, that this process generates a set of coupled nonlinear ordinary or partial differential equations. For this class of systems, the models derived from morphology of the skeleton are usually very high dimensional, nonlinear, and complex. This is particularly true if joint and link flexibility are included in the model. In addition to complexities that arise from morphology of the animal, some of the external forces that influence the dynamics of animal motion are very hard to model. A very well-established example of these forces is the unsteady aerodynamic forces applied to the wings and the body of insects, birds, and bats. These forces result from the interaction of the flapping motion of the wing and the surround- ing air. These forces generate lift and drag during flapping flight regime. As a result, they play a significant role in the description of the physics that underlies such systems. In this research we focus on dynamic and kinematic models that govern the motion of ground based robots that emulate flapping flight. The restriction to ground based biologically inspired robotic systems is predicated on two observations. First, it has become increasingly popular to design and fabricate bio-inspired robots for wind tunnel studies. Second, by restricting the robotic systems to be anchored in an inertial frame, the robotic equations of motion are well understood, and we can focus attention on flapping wing aerodynamics for such nonlinear systems. We study nonlinear modeling, identification, and control problems that feature the above complexities. This document summarizes research progress and plans that focuses on two key aspects of modeling, identification, and control of nonlinear dynamics associated with flapping flight.Ph. D.
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Teoh, Zhi Ern. "Design of Hybrid Passive and Active Mechanisms for Control of Insect-Scale Flapping-Wing Robots." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:23845481.
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Flying insects exhibit a remarkable ability to fly in environments that are small, cluttered and highly dynamic. Inspired by these animals, scientist have made great strides in understanding the aerodynamic mechanisms behind insect-scale flapping-wing flight. By applying these mechanisms together with recent advances in meso-scale fabrication techniques, engineers built an insect-scale flapping-wing robot and demonstrated hover by actively controlling the robot about its roll and pitch axes. The robot, however, lacked control over its yaw axis preventing control over its heading angle.
In this thesis, we show that the roll and pitch axes of a single actuator insect-scale flapping-wing robot can also be passively stabilized by the addition of a pair of aerodynamic dampers. We develop design guidelines for these dampers, showing that the previously unstable robot with the addition of the dampers is able to perform stable vertical flights and altitude control. To address the lack of yaw control, we develop a yaw torque generating mechanism inspired by the fruit fly wing hinge. We present the development of this mechanism in three stages: from the conceptual stage, to the torque measurement stage and finally to a hover capable stage. We show that the robot is able to generate sufficient yaw torque enabling the robot to transition from hover to heading control maneuvers.Engineering and Applied Sciences - Engineering Sciences
17
Taha, Haithem Ezzat Mohammed. "Mechanics of Flapping Flight: Analytical Formulations of Unsteady Aerodynamics, Kinematic Optimization, Flight Dynamics and Control." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/24428.
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A flapping-wing micro-air-vehicle (FWMAV) represents a complex multi-disciplinary system whose analysis invokes the frontiers of the aerospace engineering disciplines. From the aerodynamic point of view, a nonlinear, unsteady flow is created by the flapping motion. In addition, non-conventional contributors, such as the leading edge vortex, to the aerodynamic loads become dominant in flight. On the other hand, the flight dynamics of a FWMAV constitutes a nonlinear, non-autonomous dynamical system. Furthermore, the stringent weight and size constraints that are always imposed on FWMAVs invoke design with minimal actuation. In addition to the numerous motivating applications, all these features of FWMAVs make it an interesting research point for engineers.
In this Dissertation, some challenging points related to FWMAVs are considered. First, an analytical unsteady aerodynamic model that accounts for the leading edge vortex contribution by a feasible computational burden is developed to enable sensitivity and optimization analyses, flight dynamics analysis, and control synthesis. Second, wing kinematics optimization is considered for both aerodynamic performance and maneuverability. For each case, an infinite-dimensional optimization problem is formulated using the calculus of variations to relax any unnecessary constraints induced by approximating the problem as a finite-dimensional one. As such, theoretical upper bounds for the aerodynamic performance and maneuverability are obtained. Third, a design methodology for the actuation mechanism is developed. The proposed actuation mechanism is able to provide the required kinematics for both of hovering and forward flight using only one actuator. This is achieved by exploiting the nonlinearities of the wing dynamics to induce the saturation phenomenon to transfer energy from one mode to another. Fourth, the nonlinear, time-periodic flight dynamics of FWMAVs is analyzed using direct and higher-order averaging. The region of applicability of direct averaging is determined and the effects of the aerodynamic-induced parametric excitation are assessed. Finally, tools combining geometric control theory and averaging are used to derive analytic expressions for the textit{Symmetric Products}, which are vector fields that directly affect the acceleration of the averaged dynamics. A design optimization problem is then formulated to bring the maneuverability index/criterion early in the design process to maximize the FWMAV maneuverability near hover.Ph. D.
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Kurtulus, Dilek Funda. "Numerical And Experimental Analysis Of Flapping Motion In Hover. Application To Micro Air Vehicles." Phd thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606168/index.pdf.
Full textAbstract:
The aerodynamics phenomena of flapping motion in hover are considered in view of
the future Micro Air Vehicle applications. The aim of this work is to characterize the
vortex dynamics generated by the wing in motion using direct numerical simulation
and experimental analysis then to propose a simplified analytical model for
prediction of the forces in order to optimize the parameters of the motion leading to
maximum force. A great number of cases are investigated corresponding to different
angles of attack, location of start of change of incidence, location of start of change
of velocity, axis of rotation, and Re number. The airfoil used is symmetrical. The
flow is assumed to be incompressible and laminar with the Reynolds numbers
between 500 and 2000. The experimental results obtained by the laser sheet
visualization and the Particle Image Velocimetry (PIV) techniques are used in
parallel with the direct numerical simulation results for the phenomenological
analysis of the flow. The model developed for the aerodynamic forces is an indicial method based on the use of the Duhamel Integral and the results obtained by this
model are compared with the ones of the numerical simulations.
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Aktosun, Erdem. "Identification of hydrodynamic forces developed by flapping fins in a watercraft propulsion flow field." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1900.
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In this work, the data analysis of oscillating flapping fins is conducted for mathematical model. Data points of heave and surge force obtained by the CFD (Computational Fluid Dynamics) for different geometrical kinds of flapping fins. The fin undergoes a combination of vertical and angular oscillatory motion, while travelling at constant forward speed. The surge thrust and heave lift are generated by the combined motion of the flapping fins, especially due to the carrier vehicle’s heave and pitch motion will be investigated to acquire system identification with CFD data available while the fin pitching motion is selected as a function of fin vertical motion and it is imposed by an external mechanism. The data series applied to model unsteady lifting flow around the system will be employed to develop an optimization algorithm to establish an approximation transfer function model for heave force and obtain a predicting black box system with nonlinear theory for surge force with fin motion control synthesis.
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Liao, Sheng-Cih, and 廖勝次. "Novel Design of Flapping Mechanism and Wings for Flapping-Wing MAV." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/53000659546096083987.
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碩士國立勤益科技大學
機械工程系
101
This study aims at the development of a novel design of flapping mechanism and wings for flapping-wing micro air vehicles (MAVs). The flapping mechanism in the study is composed of a decelerated motor, an eccentric cam with shafts, and wings. The cam linkage, driven by the decelerated motor, activates the flapping of wings. The linkage makes the same flapped phases of two wings, which can avoid the pitches toward left or right when the MAV flies. The design of the wings is to punch holes in the wings to form one-way air flow, which can decrease the downward drag force when flapping upward and improve the lifting efficiency. This study uses working model® software to make a motion simulation analysis of flapping mechanism, from which the size of the linkage is drawn and the linkage is produced by means of rapid prototyping machines. The wings in the study are ready-made products, part of the wing skin is covered by PE films, and the frames of wings are made of 0.8mm carbon fiber rods. The airframe, micro motor, radio control module and lithium battery are made by ready-made component parts or materials on the market. The MAV of the study makes the length 25 cm, the wingspan 20 cm, and a gross weight 11 g. From the test results, it is found that the MAV has flying ability; however, the torsion of the micro motor is not high enough to lift the MAV from the ground. If the micro motor can be equipped with sufficient power, the dream that the MAV can fly can be carried out.
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HungCheng-te and 洪承德. "Analysis and Design of Flapping Wing Mechanism." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/34236972250677251222.
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碩士崑山科技大學
機械工程研究所
95
The small artificial vehicle was designed for investigating and communicating for some purposes. According the motion of small artificial vehicle’s wings, the vehicles were classified by fixed, rotational, and flapping wings. By analyzing the topological structure of flapping-wing vehicles, the object of the work is to design a (5,7) linkage as a small flapping-wing vehicle flapping with 60 digs. Upstroke angle and 30 digs. Down stroke angle. In order to analyze the motion characteristics of designed device, we see up experimental device and designed two wing length (44cm and 57cm), and four angles (6°, 8°, 11°, and 13°) between the horizontal and wing planes. The results of the experiment shows a rising force acted on designed device with 44cm wing length under the lower flapping frequency and four angles (6°, 8°, 11°, and 13°), or with 57cm wing length under the higher flapping frequency. The results prove the provided theory of this work is feasible.
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Cheng, Yuen-Jung, and 鄭元榮. "Experimental Analysis of an Flapping Wing Mechanism." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/57154570020541304864.
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碩士崑山科技大學
機械工程研究所
102
Air vehicle could be classified as fixed wing, rotational wing, and flapping wing based on the generated push and lift forces by the wing type. The advantages of air vehicle with flapping wing is light and privacy make the vehicle be more scouting such as could carry out the activities of military and disaster relief. The purpose of the study is to investigate the kinematic characteristic and flight ability of an existed air vehicle with flapping wing. First, the topological structure and the position equation of the existed air vehicle were analysis and derived. Then, an experimental device with the existed vehicle and a wind tunnel was setup and used to investigate the characteristics of push and lift forces acted by the vehicle with different wing lengths. The results show the better flight performed one is 100 cm wing length, better endurance and hovering capability ones are 110 and 120 cm wing lengths.
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Lin, Shu-Hong, and 林書弘. "On the Design of New Planar Flapping Mechanism." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/t9wzyf.
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碩士國立虎尾科技大學
動力機械工程研究所
92
The planar flapping mechanism is a kind of mechanism that makes its two different links up and down motion. Generally, the types of planar flapping mechanism are classified into four types that are four-bar linkage with five-joints, five-bar linkage with seven joints, six-bar linkage with seven-joints and seven-bar linkage with nine-joints. The purpose of this research is to proceed systematic research for design of new planar flapping mechanism in order to obtain the new planar flapping mechanism. This research carrying on the analysis and inducement of the characteristics of topologic structure and establishing the design requirements and constraints from the present mechanism. Then, based on Yan''s creative mechanism design method, type synthesis of planar flapping mechanisms are proceed. By using weighted objectives method, higher feasible new planar flapping mechanisms are chosen, which include three of four-bar linkage type, four of five-bar linkage type, one of six-bar linkage type and eleven of seven-bar linkage type of new planar flapping mechanisms. In this research, the dimensional synthesis of four of new and one existing mechanisms are selected to proceed by using vector loop method and specified input and output relation. The kinematics analysis and computer simulation of those mechanism are carried for the purpose of examining the interference did not appear during motion and satisfying the design conditions in dimensional synthesis. This research is to design the new planar flapping mechanisms systematically. The principal and methods in the study can be the important reference basis for the design of planar flapping mechanism. The achievement of this research can also be applied to simulated bird fly vehicle design for planar flapping mechanism in industrial.
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KAI, HUANG PEI, and 黃培鍇. "Design and Fabrication of the Flapping Wings Micro Aerial Vehicle With A Novel Flapping Mechanism." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/15914226365470169981.
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碩士國立勤益科技大學
機械工程系
102
For the research of the flapping-wing micro air vehicle, the paper presents a new design of the flapping mechanism. The flapping mechanism is that the flapping is driven by the reduction gear and slider crank, and makes the phases of the wing flapping consistent and then decreases the imbalance of vacillating in the process of flying. This thesis simulates and analyzes the flapping mechanism by working model software to get the better size of the transmission mechanism design, and then we use epoxy to produce the finished product. We design wing membranes with different sizes and explore their effect on lifting force. The material of the wing membrane is polyethylene terephthalate film and the framework of the wings is 0.8mm carbon fibers. The body and the tail are composed of expanded poly-propylene. The length of wingspan of the aerial vehicle is about 25 cm and the body is about 22 cm. The total weight is about 12g. We will measure the angle of attack and wing parameter under the wind-tunnel measurements. The controller is comprises of the 2.4G wireless control module and 3.7V lithium battery. The driving voltage of the motor is 3.7V DC. The maximum of rotational speed is 40000 rpm .
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Chattaraj, Nilanjan. "A Design Procedure for Flapping Wings Comprising Piezoelectric Actuators, Driver Circuit, and a Compliant Mechanism." Thesis, 2015. http://etd.iisc.ernet.in/2005/3661.
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Flapping-wing micro air vehicle (MAV) is an emerging micro-robotic technology, which has several challenges toward its practical implementation. Inspired by insect flight, researchers have adopted bio-mimicking approach to accomplish its engineering model. There are several methods to synthesize such an electromechanical system. A piezoelectric actuator driven flapping mechanism, being voltage controlled, monolithic, and of solid state type exhibits greater potential than any conventional motor driven flapping wing mechanism at small scale. However, the demand for large tip deflection with constrained mass introduces several challenges in the design of such piezoelectric actuators for this application. The mass constraint restricts the geometry, but applying high electric field we can increase the tip deflection in a piezoelectric actuator.
Here we have investigated performance of rectangular piezo-actuator at high electric field. The performance measuring attributes such as, the tip deflection, block force, block moment, block load, output strain energy, output energy density, input electrical energy, and energy efficiency are analytically calculated for the actuator at high electric field. The analytical results suggest that the performance of such an actuator can be improved by tailoring the geometry while keeping the mass and capacitance constant. Thereby, a tapered piezoelectric bimorph cantilever actuator can provide better electromechanical performance for out-of-plane deflection, compared to a rectangular piezoelectric bimorph of equal mass and capacitance. The constant capacitance provides facility to keep the electronic signal bandwidth unchanged. We have analytically presented improvement in block force and its corresponding output strain energy, energy density and energy effi- ciency with tapered geometry. We have quantitatively and comparatively shown the per- formance improvement. Then, we have considered a rigid extension of non-piezoelectric material at the tip of the piezo-actuator to increase the tip deflection. We have an- alytically investigated the effect of thick and thin rigid extension of non-piezoelectric material on the performance of this piezo-actuator. The formulation provides scope for multi-objective optimization for the actuator subjected to mechanical and electrical con- straints, and leads to the findings of some useful pareto optimal solutions. Piezoelectric materials are polarized in a certain direction. Driving a piezoelectric actuator by high electric field in a direction opposite to the polarized direction can destroy the piezo- electric property. Therefore, unipolar high electric field is recommended to drive such actuators. We have discussed the drawbacks of existing switching amplifier based piezo- electric drivers for flapping wing MAV application, and have suggested an active filter based voltage driver to operate a piezoelectric actuator in such cases. The active filter is designed to have a low pass bandwidth, and use Chebyshev polynomial to produce unipolar high voltage of low flapping frequency. Adjustment of flapping frequency by this voltage driver is compatible with radio control communication.
To accomplish the flapping-wing mechanism, we have addressed a compatible dis- tributed compliant mechanism, which acts like a transmission between the flapping wing of a micro air vehicle and the laminated piezoelectric actuator, discussed above. The mechanism takes translational deflection at its input from the piezoelectric actuator and provides angular deflection at its output, which causes flapping. The feasibility of the mechanism is investigated by using spring-lever (SL) model. A basic design of the com- pliant mechanism is obtained by topology optimization, and the final mechanism is pro- totyped using VeroWhitePlus RGD835 material with an Objet Connex 3D printer. We made a bench-top experimental setup and demonstrated the flapping motion by actuating the distributed compliant mechanism with a piezoelectric bimorph actuator.
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Ke, Hao-Hsiang, and 柯皓翔. "Weight reduction of the flapping mechanism using voice coil motor." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/826zng.
Full textAbstract:
碩士淡江大學
機械與機電工程學系碩士班
104
The objective of this research is to fabricate a voice coil motor which dedicated to flapping micro-air-vehicles (MAV) to replace the old traditional motor and reduction gear set. The goal of this research is hoping to reduce mechanical power dissipation by using the new driving mechanism. In order to design a mechanism which is suitable for voice coil motor, this study altered the driving mechanism and the interlocking device of wing. The method of making a prototype is using electrical discharge wire cutting and 3D printing. As well as the past experiment, it also collocates with the lever of Evans straight line mechanism. In addition, to operate the new flapping mechanism, this research takes advantage of Arduino board to provide positive and negative currents. With the voltage of 3.7V , when delay (ms) is set to 30 milliseconds or less, the flight frequency will be up to 16Hz . Here are two results about the new flapping mechanism. First, with wingspan of 11.5cm, the stroke angle reaches 40°to 45°. Second, with wingspan of 16.5cm and 21.5cm, the stroke angle reduced to 16° and 8°, respectively. With the lightweight M1AP Arduino board developed by Tamkang University the total mass of flapping MAV with the new mechanism will be less than 10 grams. However, the analysis of power consumption shows the friction between the magnet and the inner wall of voice coil motor is serious. After improving the mechanism, the final aim is hoped to achieve the stroke angle over 80° and the flapping frequency up to 13Hz simultaneously.
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Chang, Shih-Yuan, and 張士元. "Development of a Bending Short Flapping Mechanism for Bionic Birds." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/52216650658413057599.
Full textAbstract:
碩士崑山科技大學
機械工程研究所
103
The main purpose of this study was to mimic the wing movement of large birds, to understand required lift in the fly. The second objective is to experience the process for the development of bionic birds, through design, analysis and manufacture, and to understand the mechanical properties of the materials involved. To the current mainstream flapping-wing micro aerial vehicle (MAV) architecture research, a way of “folding design”, which is different from the regular ornithopter flapping wing mechanism, was proposed and developed. In this mechanism, the left and right wings can be simultaneously actuated by a simple combination of gears and one drive motor. With smartly designed simple linkage mechanism, both left and right wings can flap up and down. Folding wings in the up movement is to reduce air resistance when the wings rise; closed area of a predetermined main lift wing design is to increase the lift efficiency. In this study, AutoDesk Inventor® was used to design the mechanism, the majority of parts and conduct stress and strain analysis. Excepting motor and shaft with metal, synthetic material were used for most of the parts, including glass fiber, PC, ABS, acrylic, PVC and Teflon. Properties and process-ability for the above situation will also be discussed in this study. CNC milling and rapid prototyping (RP) were used on to fabricate the link mechanism with success. Although the FDM RP technology provide an convenient way of obtain complex parts, the orientation of the parts during formation plays very important role on the strength, especially for the part withstanding large dynamic force and vibration .
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Siang, Ting-Nong, and 向庭農. "Mechanism Design of Air Vehicle Wings with Rotation and Flapping." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/57009240984129446991.
Full textAbstract:
碩士國立中山大學
機械與機電工程學系研究所
104
In the modernized technology, the research of aircraft has developed from a fixed wing to a rotary wing, which imitates the flapping wings of natural creatures. In the past 30 years, more and more research teams and university organizations have involved in this research area. This thesis is to investigate the flight mechanism and aerodynamic performance of the bird and insect by selecting the mechanism that is able to rotate and flap from the special flight mechanism; objectives are set by adapting engineering design, and five-bar linkage mechanism is proposed to achieve rotary and flapping motion. Dimensional synthesis and kinematics analysis are analyzed by the adaptation of vector loop method; after the optimization of the measurement, the average error of the angle of rotation 10.3° will be obtained. Furthermore the mechanical errors caused by the linkage of revolute joints between the mechanisms are analyzed while the largest error of 55(μm) of the displacement output and the largest error of 0.89° of the angular displacement output will be obtained. To ensure the stability, the semi-circle, notch, dovetail slot, and dovetail slider are respectively adapted between two sliding surfaces of the mechanical, and bearings are attached on rotary shafts as the final mechanism design. Through the mechanical analysis to evaluate the selections of the motors and to investigate the effect that caused by the friction towards the input torque to achieve the results of the flapping frequency that is within 15Hz, and the frictional effect that is not more than 20%. As the higher the flapping frequency gets, the larger the frictional effect will become. In the end, the improvement of the dynamic equilibrium will be made, as the shaking forces in the direction of x and y are improved 44% and 30% respectively, the new model of the rotary flapping mechanism will be proposed.
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Li, Chien-Wei, and 李建緯. "Design and Analysis of a Piezoelectrically Actuated Four-Bar Flapping Mechanism." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/49946709641681660358.
Full text
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Yong, Cheng Ren, and 程仁勇. "Module Design for a Flapping Wing Simulation Mechanism With Programmable Digital Interface." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/24061806534043186135.
Full textAbstract:
碩士國立臺北教育大學
數位科技設計學系(含玩具與遊戲設計碩士班)
97
According to current research and development results, the mode of flight is generally divided into three major types, namely fixed-wing mode, rotary-wing mode, and flapping-wing mode. While there are well-developed aircraft, such as airplanes, helicopters, and so on, based on the first two modes, the unsteady state of the flapping-wing mode remains a problem to be solved by researchers. Even today, we can only make products whose functions are at best similar to the flapping-wing flight mode. This study is focused on the flapping-wing mechanism and the design of electromechanical modules. The speed and efficiency of the flapping-wing mechanism were analyzed via a human-machine interface and a control module, with reference to birds and insects, which fly on flapping wings. Thus, this study provides a front-end experiment system for product development. Based on the theory of flight and previous research results, a theoretical model was designed in this study with three-dimensional modeling software. In order to achieve a reasonable operation mode, a new mechanism design was provided to overcome the problem of the imbalance of flapping wings, and dynamic simulation and stroke ratio analysis were conducted on the flapping cycle of flapping wings. With a digital interface, the flapping-wing flight mode was analyzed through actual operation as well as simulation experiments. In short, this study analyzed dynamic feasibility and constructed a simple and well-functioning flapping-wing mechanism with programmable system control. It is hoped that this study will enable the development of a complete experiment platform for control of the flapping-wing mechanism.
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Hsin, Chao, and 陳昭欣. "The design and analysis of flapping mechanism for piezoelectrically actuated micre-air vehicles." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/48575133505500063975.
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Lin, Sheng-Wei, and 林聖偉. "On the Design of Flapping Wing Mechanism with Seven Links and Ten Joints." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/fa4tsw.
Full textAbstract:
碩士崑山科技大學
機械工程研究所
96
The small artificial vehicle was designed for investigating and communicating for some purposes. According the motion of small artificial vehicle’s wings, the vehicles were classified by fixed, rotational, and flapping wings. By analyzing the topological structure of flapping-wing vehicles, the object of the work is to design of flapping wing mechanism with seven links and ten joints with the upstroke and down stroke angle of the mechanism are 40 and 30 degrees, separately. In order to analyze the motion characteristics of designed device, we set up experimental device with 100cm wing length. The results of the experiment show the rising force acted on designed device. The results prove the provided theory of this work is feasible.
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YU, CHIEN-CHUAN, and 俞建全. "The Design and Production of a Novel Ornithopter with a new Flapping Mechanism." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/pwn62s.
Full textAbstract:
碩士東南科技大學
機械工程研究所
106
The goal of research this thesis is to use the bionic ornithopter on the market as a initial reference, second, go to the market to purchase electronic equipment that conforms the functions of the ornithopter, third, design the appearance ,the airframe and ornithopter’s flapping mechanism. After assembling and combining, the goal of making an imitation remote control ornithopter will been create. Then, make the mechamism bigger to create an eagle ornithopter, last, simulate four kinds of flapping mechanism and choose the better one to set it up. This dissertation successfully completed a flightable remote-controlled Eagle ornithopter with a 141cm wing span and a 510g weight. After the test, the number of flight hours can reach 8 to 10 minutes. So, no matter the distance or the height, both are better than commercially available toy ornithopter. This thesis also uses a simple lift experiment to test the body's changes in lift at different wind speeds and angles of attack. With the experimental data, we can more understand the influence. After the actual flight test, we also known that flying ability of the mechanism cannot achieve its maximum output when flying at too large or small of attacking angles and wind speeds. Keywords : ornithopter, bionic bird, tapping machine
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Chang, Wei-Chun, and 張維峻. "Design and Fabrication of the Micro Aerial Vehicle with a Novel Flapping Mechanism." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/18138945487379661893.
Full textAbstract:
碩士國立勤益科技大學
機械工程系
101
For the research of the flapping-wing micro air vehicle, the paper presents a new design of the flapping mechanism. The flapping mechanism is that the flapping is driven by the eccentric cam, and makes the phases of the wing flapping consistent and then decreases the imbalance of vacillating in the process of flying. Furthermore, by adjusting the eccentricity of the eccentric cam in the process of assembling, we can change the flapping amplitude of the wings. This thesis simulates and analyzes the flapping mechanism by working model software to get the better size of the transmission mechanism design, and then we use epoxy to produce the finished product. We design wing membranes with different sizes and explore their effect on lifting force. The material of the wing membrane is polyethylene terephthalate film and the framework of the wings is 0.8mm carbon fibers. The body and the tail are composed of expanded poly-propylene. The length of wingspan of the aerial vehicle is about 25 cm and the body is about 22 cm. The total weight is about 12g. We will measure the angle of attack and wing parameter under the wind-tunnel measurements. The controller is comprises of the 2.4G wireless control module and 3.7V lithium battery. The driving voltage of the motor is 3.7V DC. The maximum of rotational speed is 1200rpm and the torsion is 2.55N-m.
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Fang, Bo-Ting, and 房柏廷. "Application of the Clap and Fling Mechanism to the Development of Flapping MAVs." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/43682548129323586966.
Full textAbstract:
碩士淡江大學
機械與機電工程學系碩士班
97
The research compare to the appearance of Clap and Fling in insect, an principal object mainly base on the flapping micro aerial vehicle (MAV)-Golden snitch of TamKang University research team, improve the transmission system and devise flapping angle which makes the MAV provided Clap and Fling mechanism. An experiment Measured Aerodynamic characteristic of the flapping MAV by wind tunnel and calculate propulsive efficiency which in the result. Clap and Fling mechanism MAV discuss with whether Clap and Fling or not(Golden snitch and CF-50), transmission system(CF-50 and CF-51), stroke angle(CF-51 and CF-72). First, the research observe a wing of the MAV flapping by high speed CCD, than analyze the aerodynamic force data. The range from 0 degree to 60 degrees that produced maximum lift force in 40 degrees, golden snitch MAV`s lift force is 9.8 g, CF-50 is 9.6 g, CF-51 is 8.1 g, CF-72 is 5.5 g, and maximum flight speed in CF-50, it is 2.75 m/s, but it needed more waste power. An aspect of transmission system, flapping of single point is better than flapping of double point. An aspect of stroke angle, CF-72(72 degrees) is bad than CF-51(50 degrees), and CF-72 MAV unable to achieve vehicle weight. An aspect of propulsive efficiency the golden snitch is better than others Finally, an aspect of flight, the flight duration more than 100 seconds and complete hovering in double wings MAV (CF-110D)
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Yu, Wu Li, and 吳立羽. "Design and Fabrication of the Flapping Mechanism and Drive Circuit for Micro Aerial Vehicles." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/80465358164702695435.
Full textAbstract:
碩士國立勤益科技大學
機械工程系
103
In this thesis, we present a novel design of the flapping mechanism for the flapping-wing micro aerial vehicle. The flapping mechanism is consisted of a gear- linkage mechanism, which can make flapping of two wings in the same phase. Therefore, the wear friction will be improved and better than the slider-crank mechanism proposed by previous research. CAD Solidworks software is used for structure and interference analysis, so that the optima design of the flapping mechanism can be obtained. Protel 99SE software is used for making PCB control chip, and the electric power consumption problem is studied. In order to achieve the best flapping performance, the gear-linkage mechanism combined with homemade and commercial chips, respectively, re used for measuring the lift force and thrust force with different attack angles via wind tunnel tests. In the paper, the epoxy material is used to produce the flapping mechanism. The framework of the wings is made of 0.8mm carbon fibers. The body and the tail are composed of expanded poly-propylene. The the length of body is about 20 cm and wingspan is about 20 cm. The controller is comprised of the commercial infrared wireless control module and with 3.7V lithium battery. The driving voltage of the DC motor is 3.7Vand the maximum rotation speed is 40000 rpm. The micro aerial vehicles can fly, but due to the torsion problem of the motor and the consumption of the electric power, the fly time only tens of seconds. This will be improved in the future.
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Lai, Min-Chi, and 賴旻琦. "The Fabrication of an Electronic-Controlled Six-Degree-of-Freedom Flapping-Wing Platform: Motor Command Generator and Mechanism Simulation." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/31732400085783039167.
Full textAbstract:
碩士國立成功大學
航空太空工程學系碩博士班
95
When constructing an ornithopter, one of the technical bottlenecks is the absence of a mechanism that can flap the wing at will in the three-dimensional space. The currently available approach is to employ Crank-rocker mechanism to purely stroke the wing up and down in a plane. Therefore, it is unable to produce and control realistic aerodynamic forces for flight. This thesis makes the first attempt to realize an ornithopter by using the robotic bevel-gear wrist mechanism as a working prototype, and to study the kinematics of ornithopters in detail by robot analysis. Also, the thesis presents kinematics simulation on the designed mechanism in the software environment of Pro/E, demonstrating that the proposed mechanism can exactly imitate the complicated movements of birds' wings. Furthermore, the interactive graphical user interface developed in this thesis makes easily the design and simulation of the wingbeat kinematics, and the generation of the motor control command.
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Chiang, Yi-Wei, and 江逸偉. "Flapping mechanisms with large stroke angles." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/10429243663602360073.
Full textAbstract:
碩士淡江大學
機械與機電工程學系碩士班
100
Tamkang University MEMS group has already developed flapping wing ornithopters (MAVs) for over 9 years. The development of the 20cm-wingspan “Golden Snitch” has a flight endurance of more than 8 minutes. How to modify the flapping mechanism for the new generation of MAVs is always one of the most crucial issues. Most of the birds have their flight way mainly in gliding and loitering, and the flapping wing stroke angle is approximately 60 to 70 degrees. The hummingbirds can hover and the flapping stroke angle is 120 degrees. Bigger flapping stroke angle can do hovering better, but in the past four-bar linkage has the inevitable phase lag. The phase lag is due to the fail in mechanism symmetry and synchrony, which can cause unstable flight. The current transmission mechanism of “Golden Snitch” has the flapping wing stroke angle of 53 degrees, and the phase lag is less than 3 degrees. Improvements for the prototype of using the spring to increase the stroke angle and reduce the phase lag flapping mechanism have been demonstrated.
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Shing-Che, Li, and 李尚哲. "Analysis and Design of Floding and Flapping Wing Mechanisms." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/43550002620523856339.
Full textAbstract:
碩士崑山科技大學
機械工程研究所
95
The little air vehicles to design for adverse circumstances and investigate into danger area. The little air vehicles regard the running mode classification of the wing as the Fixed-Wing, Rotary-Wing, and Flapping-Wing etc. the three major types. According to the flight mod of the flight creature, this objective of the study is to design new folding and flapping wing mechanisms that can achieve the rotary and flapping motions. First, this work provided the requirements and constraints of folding and flapping wing mechanisms. Secondly, this work used the Yan’s creative mechanism design methodology to synthesis the feasible specialized kinematics chains and obtained satisfied morphing-wing mechanisms. Thirdly, this work designed the folding and flapping wing mechanisms dimensions by referring the flight mod of the flight creatures. Finally, we developed a computer simulation program of the designed folding and flapping wing mechanism.The results of his work are 659 new s folding and flapping wing mechanisms are designed.
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Hsu, Shu-Kai, and 許書凱. "Type synthesis and kinematic analysis of flapping-wing mechanisms." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/tsvnqb.
Full textAbstract:
碩士崑山科技大學
電機工程研究所
92
The flapping-wing mechanisms are main elements of Micro Air Vehicles that can be used to patrol the military activity or explore the danger region. Designing the flapping-wing mechanisms is to simulate the wing-motion of flying being. The purpose of this work is to present a systematic approach for designing new flapping-wing mechanisms that can simulate the wing-motion of long ear bats. First, we analyze the topological structure and motion characteristics of existed flapping-wing mechanisms. Then, the design criteria of the topological structure and motion characteristics are described. Based on the design criteria of topology, the Yan’s methodology of mechanism design is applied to synthesize new flapping-wing mechanisms. And, the kinematic equations of those new mechanisms are derived. Furthermore, the minimum error between the wing-displacements of new mechanisms and long ear bats is selected as the objective function for designing the dimensions of those new mechanisms. And, the kinematic analysis of these new mechanisms is done well. Finally, a prototype of a (6,8) flapping mechanism of long ear bats is built and tested. This research of the provide method can obtain 62 new flapping-wing mechanisms and one prototype of flapping-wing mechanism.
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Cueva, Salcedo Horacio Jesus de la. "Mechanics and energetics of ground effect in flapping flight." Thesis, 1992. http://hdl.handle.net/2429/3254.
Full textAbstract:
Ground effect (GE) is an interaction between a wing and a surface that increases
lift and reduces induced drag, stalling, minimum power, and maximum range speeds
(Vstall, Vmp,Vmr, respectively). Four bird species utilising GE during flapping flight were
studied: Double-Crested Cormorants (Pholacrocoraz auritus) at Mandarte Island B.C.,
Brown Pelicans (Pelecarius occideniali.s) at Ensenada Méico, Black Skimmers (Rynchops
niger) at San Diego California, and Barn Swallows (Hirundo rstica) at Ladner, Williams
Lake, and English Buff, B.C. Films were taken at 60—64 Hz in nature and digitised
for vertical wing displacement analysis. Flight speeds of swallows and cormorants were
measured with a Doppler radar.
Best-fit sinusoids of dicular-linear regression (Batschelet 1981), periodic ANOVA
(Bliss 1970), and Fourier series (Lighthill 1958, Bloomfield 1976) were used to describe
vertical wing movement. Linearised sinusoids were used to show vertical wing displacement
and average height of wings above the surface. Methods of evaluating GE for fixed wings
were compared to determine simple, realistic calculations for flapping flight. Average
interference coefficients were used to evaluate the influence of GE, utilising the theory of
Reid (1932). Results were compared to those for oscillating (Katz 1985 ) and banking
wings (at an angle to the horizontal) (Binder 1977).
The effect of GE on the daily energy balance (DEB) was evaluated in cormorants.
DEBs were constructed considering GE, metabolic, reproductive, and fight costs. Power
curves were constructed using fixed-wing quasi-steady aerodynamic theory (Pennycuick
1975). Flight speeds Vmp=10.9 ms-1 out of ground effect (OGE), 6 ms-1, in GE
(IGE), arid Vmr=16.3 ms-1 OGE, 15.4 ms-1 IGE and flight costs IGE and OGE of
cormorants were compared to speeds measured during the 1987 and 1988 reproductive
seasons. Cormorants observed at Mandarte Island obtain savings of up to 40% of total
power when flying in GE. If cormorants fly with a fixed cargo per trip (0.3 kg) from the feeding site to the nest the predicted number of trips per day is 3—4 as observed by
Robertson (1971). Cost of Transport (cost of moving a unit weight a unit distance) was
compared for flights IGE and OGE, with and without a load. Foraging radius (Pennycuick,
1979) calculates maximum distance travelled on available energy. Foraging radii ICE and
OGE of double-crested cormorants limit potential food sources. Flight IGE is significantly
cheaper than OGE for the double-crested cormorant.
Flight energy expenditures were compared for the four species. Swallows and skimmers
show savings of up to 50% when IGE, but most savings are obtained only at speeds <8
ms-1. Cormorants and pelicans showed energy savings going from 5% at speeds > 15
ms-1 to 20% at speeds <8 ms-1
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Liu, Feng-Chi, and 劉峰齊. "Creative Design of Flapping-Wing Mechanisms with Single Degree of Freedom." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/d3cya6.
Full textAbstract:
碩士崑山科技大學
機械工程研究所
92
People used the Micro Air Vehicles to patrol the military activity or explore the danger region. The important parts of Micro Air Vehicles are the flapping mechanisms those can simulate the wing-motion of flying being. Hence this work is to present a systematic approach for designing new flapping mechanisms with one degree of freedom that can simulate the wing-motion of long ear bats and insects. First, we analyze the topological structure and motion characteristics of existed flapping mechanisms. Then, the design criteria of the topological structure and motion characteristics are described. Based on the design criteria of topology, the Yan’s methodology of mechanism design is applied to synthesize new flapping mechanisms. And, the kinematic equations of those new mechanisms are derived. Furthermore, the minimum error between the wing-displacements of new mechanisms and long ear bats is selected as the objective function for designing the dimensions of those new mechanisms. And, the kinematic analysis of these new mechanisms is done well. Finally, a prototype of a (5,7) flapping mechanism of insects is built and tested. This research of the provide method can obtain 94 new flapping mechanisms and one prototype of a flying insect mechanism.
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Hung, Kun-Chuan, and 洪堃銓. "Design and Manufacture of Hummingbird-like Flapping Mechanisms and Plastic Kits." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/8vsw3w.
Full textAbstract:
碩士淡江大學
機械與機電工程學系碩士班
102
In the body of research relevant to versatile flapping micro-air-vehicles (MAV), design and development of light-weight and energy-efficient flapping mechanisms occupies a position of primacy due to its immense impact on the flight performance and mission capability. Realization of a compact flapping mechanism that can produce adequate aerodynamic force for fulfilling the requirements of cruising forward flight and vertical take-off and landing (VTOL) needs the combination of the four-bar-linkage (FBL) and Evan''s straight line mechanism. This paper presents the concerted approach adopted for developing the flapping wing mechanisms for 20 cm span flapping MAVs through an iterative approach involving three design iterations on mechanisms and multiple fabrications approaches such as electrical-discharge-wire-cutting (EDWC) and plastics injection molding. The minimum mass of the polyoxymethylene (POM) mechanism is only 1.78 gram and the maximum flapping frequency is 18.86 Hz. Performance characteristics for each mechanism are evaluated through high speed photography, power take-off measurement, wind tunnel testing and test flights. The maximum lift is 13.4 gram force under the angle of attack of 70° and is beyond the total mass 9.7 gram of the MAV. The resultant flapping mechanism with almost non-existent phase lag between the wings and the extra large flapping stroke up to 120 like birds push this 20 cm-span flapping MAV up to 20 m high in 24 sec.
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Hsu, Chia-Ren, and 許嘉仁. "On the Dynamic Analysis and Optimal Design of Planar Flapping Mechanisms." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/8f38r7.
Full textAbstract:
碩士國立虎尾科技大學
動力機械工程研究所
93
The purpose of this research is to proceed the dynamic analysis and optimum design of the Planar Flapping Mechanisms. By using the Vector Loop method, the motion of four types flapping mechanisms are analyzed. The generalized equations of motion are established and the motions are simulated by the Fourth-Order Runge-Kutta numerical method. Moreover, the kinetostatic analysis of flapping mechanisms is also analyzed. The results can be as the basis in the aspect of dynamic design of flapping mechanisms. This research defines the maximum mechanical advantage of the mechanism as the objective function for the optimum design of the link lengths of the flapping mechanisms. According to the results of optimum design, the mechanical advantage and flap angle range of wing links are re-analyzes. The results show that the mechanical advantage of flapping mechanisms will be higher than the original mechanisms after optimum design processes are carried. The principle and method of this research can be applied to the dynamic analysis and optimum design of others planar mechanism.
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Huang, Chun-Hao, and 黃俊豪. "On the Experimental Analysis and Dynamic Characteristic Design of Flapping Wing Mechanisms with Eight Links and Eleven Joints." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/08936541920620929675.
Full textAbstract:
碩士崑山科技大學
機械工程研究所
98
Based on the unique wing and flight motion design, small aircraft can fly under the special circumstances to perform exploration and communication functions. There are three kinds wing design like as fixed wing, rotation wing, and flapping wing for help the flapping wing mechanism to achieve the functions. The purpose of this study is to analyze the kinematic model of flapping wing animals, design and produce a (8, 11) flapping wing mechanism with approximate flight of birds. First, we investigate the topological structure characteristic of flapping wing mechanisms. According the characteristic to design and produce a flapping wing mechanism with eight links and eleven joints. Then, derived the motion equations of the mechanism to correspond to up stroke angle 40° and down stroke angle 30°. Finally, we design 6 different wing dimensions for experimental analysis and dynamic characteristic for the function achievement. The design and experimental results show the feasibility of the proposed method.