How flight feathers stick together to form a continuous morphing wing

Science ◽  
2020 ◽  
Vol 367 (6475) ◽  
pp. 293-297 ◽  
Author(s):  
Laura Y. Matloff ◽  
Eric Chang ◽  
Teresa J. Feo ◽  
Lindsie Jeffries ◽  
Amanda K. Stowers ◽  
...  
Keyword(s):  
Connective Tissue ◽  
Bird Species ◽  
Elastic Compliance ◽  
Morphing Wing ◽  
Morphing Aircraft ◽  
Morphing Wings ◽  
Aerial Robot

Variable feather overlap enables birds to morph their wings, unlike aircraft. They accomplish this feat by means of elastic compliance of connective tissue, which passively redistributes the overlapping flight feathers when the skeleton moves to morph the wing planform. Distinctive microstructures form “directional Velcro,” such that when adjacent feathers slide apart during extension, thousands of lobate cilia on the underlapping feathers lock probabilistically with hooked rami of overlapping feathers to prevent gaps. These structures unlock automatically during flexion. Using a feathered biohybrid aerial robot, we demonstrate how both passive mechanisms make morphing wings robust to turbulence. We found that the hooked microstructures fasten feathers across bird species except silent fliers, whose feathers also lack the associated Velcro-like noise. These findings could inspire innovative directional fasteners and morphing aircraft.

scholarly journals Bioinspired morphing wings for extended flight envelope and roll control of small drones

2017 ◽  
Vol 7 (1) ◽  
pp. 20160092 ◽  
Author(s):  
M. Di Luca ◽  
S. Mintchev ◽  
G. Heitz ◽  
F. Noca ◽  
D. Floreano
Keyword(s):  
Bird Species ◽  
Aerodynamic Performance ◽  
High Wind ◽  
Morphing Wing ◽  
Wind Resistance ◽  
Ground Speed ◽  
Roll Control ◽  
High Speeds ◽  
Morphing Wings ◽  
Wind Tunnel Measurements

Small-winged drones can face highly varied aerodynamic requirements, such as high manoeuvrability for flight among obstacles and high wind resistance for constant ground speed against strong headwinds that cannot all be optimally addressed by a single aerodynamic profile. Several bird species solve this problem by changing the shape of their wings to adapt to the different aerodynamic requirements. Here, we describe a novel morphing wing design composed of artificial feathers that can rapidly modify its geometry to fulfil different aerodynamic requirements. We show that a fully deployed configuration enhances manoeuvrability while a folded configuration offers low drag at high speeds and is beneficial in strong headwinds. We also show that asymmetric folding of the wings can be used for roll control of the drone. The aerodynamic performance of the morphing wing is characterized in simulations, in wind tunnel measurements and validated in outdoor flights with a small drone.

Numerical study of geometric morphing wings of the 1303 UCAV

2021 ◽  
pp. 1-17
Author(s):  
B. Nugroho ◽  
J. Brett ◽  
B.T. Bleckly ◽  
R.C. Chin
Keyword(s):  
Flight Control ◽  
Numerical Study ◽  
Aerodynamic Characteristics ◽  
Morphing Wing ◽  
Rolling Moment ◽  
Wide Range ◽  
Morphing Wings ◽  
Wing Geometry ◽  
Lift And Drag ◽  
Wing Morphing

ABSTRACT Unmanned Combat Aerial Vehicles (UCAVs) are believed by many to be the future of aerial strike/reconnaissance capability. This belief led to the design of the UCAV 1303 by Boeing Phantom Works and the US Airforce Lab in the late 1990s. Because UCAV 1303 is expected to take on a wide range of mission roles that are risky for human pilots, it needs to be highly adaptable. Geometric morphing can provide such adaptability and allow the UCAV 1303 to optimise its physical feature mid-flight to increase the lift-to-drag ratio, manoeuvrability, cruise distance, flight control, etc. This capability is extremely beneficial since it will enable the UCAV to reconcile conflicting mission requirements (e.g. loiter and dash within the same mission). In this study, we conduct several modifications to the wing geometry of UCAV 1303 via Computational Fluid Dynamics (CFD) to analyse its aerodynamic characteristics produced by a range of different wing geometric morphs. Here we look into two specific geometric morphing wings: linear twists on one of the wings and linear twists at both wings (wash-in and washout). A baseline CFD of the UCAV 1303 without any wing morphing is validated against published wind tunnel data, before proceeding to simulate morphing wing configurations. The results show that geometric morphing wing influences the UCAV-1303 aerodynamic characteristics significantly, improving the coefficient of lift and drag, pitching moment and rolling moment.

scholarly journals Design of compliant mechanism-based variable camber morphing wing with nonlinear large deformation

2019 ◽  
Vol 16 (6) ◽  
pp. 172988141988674 ◽  
Author(s):  
Yaqing Zhang ◽  
Wenjie Ge ◽  
Ziang Zhang ◽  
Xiaojuan Mo ◽  
Yonghong Zhang
Keyword(s):  
Large Deformation ◽  
Compliant Mechanisms ◽  
Compliant Mechanism ◽  
Leading Edge ◽  
Aerodynamic Performance ◽  
Flight Performance ◽  
Morphing Wing ◽  
Structure Topology ◽  
Trailing Edges ◽  
Morphing Wings

The morphing wing with large deformation can benefit its flight performance a lot in different conditions. In this study, a variable camber morphing wing with compliant leading and trailing edges is designed by large-displacement compliant mechanisms. The compliant mechanisms are carried out by a hyperelastic structure topology optimization, based on a nonlinear meshless method. A laminated leading-edge skin is designed to fit the curvature changing phenomenon of the leading edge during deformation. A morphing wing demonstrator was manufactured to testify its deformation capability. Comparing to other variable camber morphing wings, the proposal can realize larger deflection of leading and trailing edges. The designed morphing wing shows great improvement in aerodynamic performance and enough strength to resist aerodynamic and structural loadings.

scholarly journals Design and analysis of a linear servo-actuated variable-span morphing wing

2020 ◽  
Vol 12 (4) ◽  
pp. 71-82
Author(s):  
Aynul HOSSAIN ◽  
Wei WANG ◽  
Hailong YUE
Keyword(s):  
Technology Development ◽  
Shape Change ◽  
Current Trend ◽  
Flight Performance ◽  
Morphing Wing ◽  
Sensors And Actuators ◽  
Morphing Aircraft ◽  
Change Mechanisms ◽  
Variable Span ◽  
Smart Technologies

Morphing aircraft are multi-role aircraft that change their external shape substantially to adapt to a changing mission environment during flight. Current interest in morphing vehicles has been increased by advances in smart technologies such as materials, sensors and actuators. These advances have led to a series of breakthroughs in a wide variety of disciplines that, when fully realized for aircraft applications, have the potential to produce large improvements in aircraft safety, affordability, and environmental compatibility. Morphing wing designs include rotating, sliding and inflating based on shape change mechanisms. The current trend in technology development shows that there is lots to improve with regards to aircraft size, flying range and flight performance envelope. There should be a balance between shape change and the penalties in cost, complexity and weight. Final performance of the morphing aircraft depends heavily on how such balances in design, manufacture and morphing mechanism can be achieved. This paper was an attempt to design and perform a further analysis of an efficient variable span wing for aircraft and fixed wing UAVs.

scholarly journals Conceptual Design Of A Modular Morphing Wing

2021 ◽  
Author(s):  
Allan D. Finistauri
Keyword(s):  
Modular Design ◽  
Design Method ◽  
Connectivity Analysis ◽  
Morphing Wing ◽  
Kinematic Constraint ◽  
Limited Mobility ◽  
System A ◽  
Morphing Wings ◽  
Wing Skin ◽  
Variable Geometry Truss

In this dissertation a new modular design method for morphing wings is presented. First, a design method was created, applying modularity and recon gurability to a morphing wing system. With modularity being a requirement for the morphing wing system, a discretization method is developed to determine the discrete number of modules required to perform a desired morphing maneuver. Then, a specialized, modular, recon gurable variable geometry truss mechanism is proposed to facilitate morphing. The specialized modular wing truss is a recon gurable, limited mobility parallel mechanism, adapted to t within the volume of a wing. The mobility of the wing truss module is analyzed via a branch-based mobility and connectivity analysis that imposes kinematic requirements on the truss mechanism. The mobility and connectivity requirements are used to perform an enumeration analysis to isolate candidate module con gurations for morphing. Then, a parametric kinematic constraint system is developed and applied to the wing module and the kinematic performance of the module is evaluated. The kinematics are applied to a mechanical prototype of the wing module for validation purposes. Finally, the kinematics are used to evaluate the motion response of a wing skin system to lay the foundation for detailed design.

Morphing wings review: aims, challenges, and current open issues of a technology

2020 ◽  
pp. 095440622094442
Author(s):  
S Ameduri ◽  
A Concilio
Keyword(s):  
Critical Review ◽  
Morphing Wing ◽  
Growth Trend ◽  
Aerodynamic Efficiency ◽  
Load Transmission ◽  
Morphing Wings ◽  
Current Growth ◽  
Critical Components ◽  
Primary Impact ◽  
Open Issues

The scope of this work is to provide a critical review on the expectations about the morphing wing technology against the current open issues and showstoppers. In synergy to other emerging and promising technologies, morphing is asked for bridging the evident gap between the current growth trend of the aerospace compartment and its impact onto the environment. The potential of morphing, in particular, its primary impact on the aerodynamic efficiency of the aircraft, primed the investigation of different technologies, achieving interesting results but often highlighting limitations and showstoppers against the airworthiness regulations. The authors focus their attention on some specific aspects that characterize the morphing wing attachments and that may represent weakness points for the maturation of the technology: the load transmission of the movable parts to the supporting wing box, the way the flexibility–rigidity paradox is addressed by specific critical components (the skin), the scalability dependence of the morphing architectures, and the specific aeroelastic behavior of the nonconventional architectures.

scholarly journals Aeroelastic behaviour of UAV wings due to morphing

2017 ◽  
Vol 89 (1) ◽  
pp. 30-38 ◽  
Author(s):  
Levent Ünlüsoy ◽  
Yavuz Yaman
Keyword(s):  
Structural Model ◽  
High Efficiency ◽  
Morphing Wing ◽  
Element Analysis ◽  
Content Type ◽  
Aerodynamic Model ◽  
Morphing Wings ◽  
Fast Solution ◽  
Order Of Magnitude ◽  
Aerial Vehicle

Purpose The purpose of this paper is to analyse the effects of morphing on the aeroelastic behaviour of unmanned aerial vehicle (UAV) wings to make an emphasis on the required aeroelastic tailoring starting from the conceptual design of the morphing mechanisms. Design/methodology/approach In this study, flutter and divergence characteristics of a fully morphing wing design were discussed to show the dilapidating effect of morphing on the related parameters. The morphing wings were intended to achieve a high efficiency at different flight phases; thus, various morphing concepts were integrated into a UAV wing structure. Although it is considered beneficial to have the morphing capabilities to avoid the failure due to a possible wear out in flutter and divergence parameters; it is necessary to include the aeroelastic analyses at the early design phases. This study utilizes a combination of a reduced order structural model and Theodorsen unsteady aerodynamic model as primary analyses tools for flutter and divergence. The analyses were conducted by using an in-house developed pk-algorithm coupled with a commercial finite element analysis (FEA) tool. This approach yielded a fast solution capacity because of the state-space form used. Findings Analyses conducted showed that transition between take-off, climb, cruise and loiter phases yield a change in the flutter and divergence speeds as high as 138 and 305 per cent, respectively. Practical implications The research showed that an extensive aeroelastic investigation was required for morphing wing designs to achieve a failure safe design. Originality/value The research intends to highlight the possible deteriorating effects on structural design of morphing UAV wings by focusing on the aeroelastic characteristics. In addition to that, fundamental morphing concepts are compared in terms of the order of magnitude of their deteriorating effects.

scholarly journals Simplified 2D Skin Lattice Models for Multi-Axial Camber Morphing Wing Aircraft

Aerospace ◽  
2019 ◽  
Vol 6 (8) ◽  
pp. 90
Author(s):  
Bashir Alsaidi ◽  
Woong Yeol Joe ◽  
Muhammad Akbar
Keyword(s):  
Structural Strength ◽  
Lattice Models ◽  
Structure Design ◽  
Design Stage ◽  
Design Parameters ◽  
Main Theme ◽  
Morphing Wing ◽  
Morphing Wings ◽  
Plate Models ◽  
Selection Of

Conventional fixed wing aircraft require a selection of certain thickness of skin material that guarantees structural strength for aerodynamic loadings in various flight modes. However, skin structures of morphing wings are expected to be flexible as well as stiff to structural and coupled aerodynamic loadings from geometry change. Many works in the design of skin structures for morphing wings consider only geometric compliance. Among many morphing classifications, we consider camber rate change as airfoil morphing that changes its rate of the airfoil that induces warping, twisting, and bending in multi-axial directions, which makes compliant skin design for morphing a challenging task. It is desired to design a 3D skin structure for a morphing wing; however, it is a computationally challenging task in the design stage to optimize the design parameters. Therefore, it is of interest to establish the structure design process in rapid approaches. As a first step, the main theme of this study is to numerically validate and suggest simplified 2D plate models that fully represents multi-axial 3D camber morphing. In addition to that, the authors show the usage of lattice structures for the 2D plate models’ skin that will lead to on-demand design of advanced structure through the modification of selected structure.

scholarly journals Synthesis, Analysis, and Design of a Novel Mechanism for the Trailing Edge of a Morphing Wing

Aerospace ◽  
2018 ◽  
Vol 5 (4) ◽  
pp. 127 ◽  
Author(s):  
Harun Levent Şahin ◽  
Yavuz Yaman
Keyword(s):  
Dynamic Force ◽  
Morphing Wing ◽  
Trailing Edge ◽  
Aerodynamic Efficiency ◽  
Structural Mechanism ◽  
Analysis And Design ◽  
Design Error ◽  
Morphing Wings ◽  
Wing Skin ◽  
Four Bar Linkage

In the design and analysis of morphing wings, several sciences need to be integrated. This article tries to answer the question, “What is the most appropriate actuation mechanism to morph the wing profile?” by introducing the synthesis, analysis, and design of a novel scissor-structural mechanism (SSM) for the trailing edge of a morphing wing. The SSM, which is deployable, is created via a combination of various scissor-like elements (SLEs). In order to provide mobility requirements, a four-bar linkage (FBL) is assembled with the proposed SSM. The SSM is designed with a novel kinematic synthesis concept, so it follows the airfoil camber with minimum design error. In this concept, assuming a fully-compliant wing skin, various types of SLEs are assembled together, and emergent SSM provide the desired airfoil geometries. In order to provide the required aerodynamic efficiency of newly-created airfoil geometries and obtain pressure distribution over the airfoil, two-dimensional (2D) aerodynamic analyses have been conducted. The analyses show similar aerodynamic behavior with the desired NACA airfoils. By assigning the approximate link masses and mass centers, the dynamic force analysis of the mechanism has also been performed, and the required torque to drive the newly-developed SSM is estimated as feasible.

scholarly journals Multidisciplinary multi-objective design optimization of an active morphing wing section

2020 ◽  
Vol 62 (5) ◽  
pp. 2423-2440
Author(s):  
Florian Dexl ◽  
Andreas Hauffe ◽  
Klaus Wolf
Keyword(s):  
A Priori ◽  
Cellular Systems ◽  
Multidisciplinary Optimization ◽  
Morphing Wing ◽  
Linear Contraction ◽  
Active Structure ◽  
Design And Optimization ◽  
Target Shape ◽  
Wing Section ◽  
Morphing Wings

Abstract Design and optimization of morphing wings are of current research interest as they promise increasing efficiency and flexibility of future aircraft. A challenging task is to find structural layouts of morphing wings that enable aerodynamically optimized shape changes without defining the target shape a priori. The current paper addresses this task and presents a method that combines the optimization of the active structure of a wing section, parameterized by Lindenmayer cellular systems, with an aerodynamic evaluation. Neither the structural layout nor the target shape has to be defined a priori. This aim is achieved by a multidisciplinary optimization using evolutionary algorithms with aerodynamic and structural objectives. The developed method allows to optimize the topology of the internal structure, the placement of linear contraction, and expansion actuators as well as the setting of their actuation degree concurrently. It is shown that the present approach allows to find optimized internal layouts containing active structural elements for morphing wing sections.

Sign in / Sign up

Export Citation Format

Share Document