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Hydrodynamic Performance of Aquatic Flapping: Efficiency of Underwater Flight in the Manta Open
The manta is the largest marine organism to swim by dorsoventral oscillation (flapping) of the pectoral fins. The manta has been considered to swim with a high efficiency stroke, but this assertion has not been previously examined. The osc…
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Dove: A biomimetic flapping-wing micro air vehicle Open
This paper describes the design and development of the Dove, a flapping-wing micro air vehicle (FWMAV), which was developed in Northwestern Polytechnical University. FWMAVs have attracted international attentions since the past two decades…
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Agile Robotic Fliers: A Morphing-Based Approach Open
The aerial robot presented here for the first time was based on a quadrotor structure, which is capable of unique morphing performances based on an actuated elastic mechanism. Like birds, which are able to negotiate narrow apertures despit…
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Physical limits of flight performance in the heaviest soaring bird Open
Significance Flapping flight is extremely costly for large birds, yet little is known about the conditions that force them to flap. We attached custom-made “flight recorders” to Andean condors, the world’s heaviest soaring birds, documenti…
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Development of a Solar-Powered Unmanned Aerial Vehicle for Extended Flight Endurance Open
Having an exciting array of applications, the scope of unmanned aerial vehicle (UAV) application could be far wider one if its flight endurance can be prolonged. Solar-powered UAV, promising notable prolongation in flight endurance, is dra…
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Key Anthropometric and Physical Determinants for Different Playing Positions During National Basketball Association Draft Combine Test Open
Annual draft combine test of National Basketball Association (NBA) is a key player testing process where prospective players with extraordinary athletic abilities are evaluated and the assessment results would further inform the determinat…
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Bioinspired Flapping-Wing Robot With Direct-Driven Piezoelectric Actuation and Its Takeoff Demonstration Open
In this letter, we present the design and the performance of a prototype bioinspired flapping-wing micro aerial vehicle with piezoelectric direct-driven actuation.This type of actuation is superior in terms of structural simplicity because…
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Testing of a Hinged Wingtip Device for Gust Loads Alleviation Open
Recent aircraft designs have considered higher aspect ratio wings to reduce induced drag for improved fuel efficiency; however, to remain compliant with airport gate requirements, folding wing-tips have been introduced as a solution to the…
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PV System Design and Flight Efficiency Considerations for Fixed-Wing Radio-Controlled Aircraft—A Case Study Open
The list of photovoltaic (PV) applications grows longer every day with high consideration for system efficiency. For instance, in spite of many recent PV aircraft designs, aircraft propulsion was mainly reserved for nonelectric motors. Lat…
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A Novel Actuation Strategy for an Agile Bioinspired FWAV Performing a Morphing-Coupled Wingbeat Pattern Open
Flying vertebrates exhibit sophisticated wingbeat kinematics. Their\nspecialized forelimbs allow for the wing morphing motion to couple with the\nflapping motion during their level flight, Previous flyable bionic platforms\nhave successful…
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Energy Management of Solar-Powered Aircraft-Based High Altitude Platform for Wireless Communications Open
With the increasing interest in wireless communications from solar-powered aircraft-based high altitude platforms (HAPs), it is imperative to assess the feasibility of their deployment in different locations with the constraints on energy …
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Bumblebees perceive the spatial layout of their environment in relation to their body size and form to minimize inflight collisions Open
Significance Like many other animals, including humans, insects frequently move through densely cluttered environments to perform activities critical for their survival, such as foraging. Vertebrates avoid collisions by perceiving their su…
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Bio-Inspired Propulsion: Towards Understanding the Role of Pectoral Fin Kinematics in Manta-like Swimming Open
Through computational fluid dynamics (CFD) simulations of a model manta ray body, the hydrodynamic role of manta-like bioinspired flapping is investigated. The manta ray model motion is reconstructed from synchronized high-resolution video…
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Wing wear reduces bumblebee flight performance in a dynamic obstacle course Open
Previous work has shown that wing wear increases mortality in bumblebees. Although a proximate mechanism for this phenomenon has remained elusive, a leading hypothesis is that wing wear increases predation risk by reducing flight manoeuvra…
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Aspect ratio studies on insect wings Open
The wing aspect ratio (AR), that is, the ratio of the wingspan to the mean wing chord, is the most important geometrical parameter describing an insect wing. While studies have shown that a change in AR affects the flow structure as well a…
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Neck biomechanics indicate that giant Transylvanian azhdarchid pterosaurs were short-necked arch predators Open
Azhdarchid pterosaurs include the largest animals to ever take to the skies with some species exceeding 10 metres in wingspan and 220 kg in mass. Associated skeletons show that azhdarchids were long-necked, long-jawed predators that combin…
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Roles of wing flexibility and kinematics in flapping wing aerodynamics Open
Insects are excellent fliers because of their ability to generate precise wing kinematics and deform their wings for the sufficient production of unsteady aerodynamic forces. Most of the previous studies on the effects of wing kinematics o…
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Raptor wing morphing with flight speed Open
In gliding flight, birds morph their wings and tails to control their flight trajectory and speed. Using high-resolution videogrammetry, we reconstructed accurate and detailed three-dimensional geometries of gliding flights for three rapto…
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Aerodynamic consequences of wing morphing during emulated take-off and gliding in birds Open
Birds morph their wings during a single wingbeat, across flight speeds, and among flight modes. Such morphing may allow them to maximize aerodynamic performance, but this assumption remains largely untested. We tested the aerodynamic perfo…
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Perpetual flight with a small solar-powered UAV: Flight results, performance analysis and model validation Open
This paper presents the design of the small-scale hand-launchable solar-powered AtlantikSolar UAV, summarizes flight results of a continuous 28-hour solar-powered flight that demonstrated AtlantikSolar's capability for energetically perpet…
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Flight control of a large-scale flapping-wing flying robotic bird: System development and flight experiment Open
Large-scale flapping-wing flying robotic birds have huge application potential in outdoor tasks, such as military reconnaissance, environment exploring, disaster rescue and so on. In this paper, a multiple modes flight control method and s…
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Conceptual design and optimization of a tilt-rotor micro air vehicle Open
The conceptual design and optimization of a tilt-rotor Micro Air Vehicle (MAV) for a well-defined mission are performed. The objective of this design cycle is to decrease the design time in order to efficiently create a functional tilt-rot…
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Conceptual Design of a Hybrid Hydrogen Fuel Cell/Battery Blended-Wing-Body Unmanned Aerial Vehicle—An Overview Open
The manuscript presents the conceptual design phase of an unmanned aerial vehicle, with the objective of a systems approach towards the integration of a hydrogen fuel-cell system and Li-ion batteries into an aerodynamically efficient platf…
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Design and fabrication of a fixed-wing Unmanned Aerial Vehicle (UAV) Open
Unmanned Aerial Vehicles (UAVs) have been widely used both in military and civil across the world in recent years. Nevertheless, their design always involves complex design optimization variables and decisions. Therefore, this paper aims t…
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HIT-Hawk and HIT-Phoenix: Two kinds of flapping-wing flying robotic birds with wingspans beyond 2 meters Open
Inspired by large and medium-sized birds, two kinds of flapping-wing flying robots with wingspans beyond 2 meters were developed. They have the appearance of a hawk and a phoenix respectively, so they are called HIT-Hawk and HIT-Phoenix. I…
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Force generation and wing deformation characteristics of a flapping-wing micro air vehicle ‘DelFly II’ in hovering flight Open
The study investigates the aerodynamic performance and the relation between wing deformation and unsteady force generation of a flapping-wing micro air vehicle in hovering flight configuration. Different experiments were performed where fl…
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Fruit fly scale robots can hover longer with flapping wings than with spinning wings Open
Hovering flies generate exceptionally high lift, because their wings generate a stable leading edge vortex. Micro flying robots with a similar wing design can generate similar high lift by either flapping or spinning their wings. While it …
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Wake structure and kinematics in two insectivorous bats Open
We compare kinematics and wake structure over a range of flight speeds (4.0–8.2 m s −1 ) for two bats that pursue insect prey aerially, Tadarida brasiliensis and Myotis velifer . Body mass and wingspan are similar in these species, but M. …
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Aircraft Charging and its Influence on Triggered Lightning Open
This paper reports on a laboratory experiment to study the effect of vehicle net charge on the inception of a positive leader from an aircraft exposed to high atmospheric electric fields. The experiment models the first stage of aircraft‐t…
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Sizing High-Aspect-Ratio Wings with a Geometrically Nonlinear Beam Model Open
This study considers the effect of geometric nonlinearity at the design concept stage of an aircraft wing. A nonlinear finite element beam model adopting the finite volumes concept with an intrinsic strain and curvature formulation is used…