UNCLASSIFIED

UNCLASSIFIED

EXPERIMENTAL METHODS FOR

MULTI-GENRE NETWORKSObjectives• Contribute to the development of a span-wise wing

morphing for small unmanned aerial systems (UAS).

• Design and optimize an internal wing structure capable

of > 50% span area change

• Utilize a tensegrity structure to manipulate axial and

bending stiffnesses independently

• Explore materials for internal structure and wing skin

• Ideal structure should be low in density, with lower axial stiffness, but higher transverse stiffness

Challenges• Designing and manufacturing a wing morphing system

using Additive Manufacturing with controlled directional

stiffness is difficult

• A recently developed morphing wing is capable of

achieving 100% span-wise extension, but transverse

stiffness is too low, causing out-of-plan bending

• Designing a structure with low density and low axial

stiffness can result in plastic deformation

• Existing design concepts that meet all objectives have

nonuniform airfoil shape which impacts Aerodynamic performance

Proposed Concepts

Tensegrity Metastructure

Platform Design and Control

[Campaign Tier 4]

POC: Daniel Okegbu, dokegbu3@gatech.edu

Funding Type: 6.2, Mission Funding

Project Size: Medium

Duration: FY18 – FY24

Simulation Results

Discussion & Conclusions

Future Design Workflow

Tensegrity Inspired Span-

Wise Wing Morphing

Bending (Out-of-Plane)Bending (In-Plane)

SolidWorks

HyperMesh

Abaqus CAEPACE

Supercomputer

Abaqus Viewer

MATLAB Programming

Abaqus CAE

Main advantages:• Ability to easily compress

• Structure returns back to original shape once unloaded (i.e., Elastic)

• Strain energy of structure stored both in cables and bars

• Current design requires less force compared to conventional tensegrity

• Ability to manipulate bars for axial stiffness

• Ability to manipulate cables for bending stiffness

Fundamental concept:• Bars under pure compression

• Cables under pure tension

• Bars in compression are isolated by cables in tension

Compression

Prototype 1 Prototype 2

Prototype 3: Tensegrity Lattice

Increasing bending Stiffness

Decreasing Axial Stiffness

•To lower axial stiffness of the structure, the bars can be rotated to a direction

with the least resistance to compression

•Decreasing the cross-sectional area of the bar reduces required force for

compression

•Pre-buckling the bar shape reduces the required force for compression

•Simulation result shows that tensegrity lattice can achieve up to ~45%

compression before bars start making contact. Structure’s extension can

also be tested

•Tolerable amount of local plasticity was observed in cables

•Force displacement curve of bending in out-of-plane direction is lower

compared to that of an in-plane direction

•Stacking the unit cells offers an additional parameter to study bending

stiffness

•Cables contributing to lower bending stiffness are highlighted in red

•To improve bending stiffness, the cross-sectional area of selected cables is

increased as highlighted in green

•Due to the geometric complexity of tensegrity,

simulations are computationally expensive

•A programmable route will allow for faster

parametric study

Current workflow

Future workflow