Experimental and computational assessment of a shape memory alloy based morphing wing incorporating linear and non-linear control

An active structure of a morphing wing designed for subsonic cruise flight conditions is composed of three principal subsystems: (1) flexible extrados, (2) rigid intrados, and (3) an actuator group located inside the wing box. The four-ply laminated composite flexible extrados is powered by two individually controlled shape memory alloy (SMA) actuators. Fulfilling the requirements imposed by the morphing wing application to the force-displacement characteristics of the actuators, a novel design methodology to determine the geometry of the SMA active elements and their adequate assembly conditions is presented. This methodology uses the results of the constrained recovery testing of the selected SMA. Using a prototype of the morphing laminar wing powered by SMA actuators, the design approach proposed in this study is experimentally validated.

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Nano-Positioning with Ferromagnetic Shape Memory Alloy Actuators

Materials Science Forum ◽

10.4028/www.scientific.net/msf.635.201 ◽

2009 ◽

Vol 635 ◽

pp. 201-205 ◽

Cited By ~ 4

Author(s):

Estibalitz Asua ◽

Jorge Feuchtwanger ◽

Alfredo García-Arribas ◽

Victor Etxebarria ◽

José M. Barandiarán

Keyword(s):

Shape Memory Alloy ◽

Single Crystal ◽

Shape Memory ◽

Active Element ◽

Ferromagnetic Shape Memory Alloy ◽

Force And Motion ◽

Non Linear ◽

Ferromagnetic Shape Memory ◽

20 Nm ◽

Laboratory Prototype

Ferromagnetic shape memory alloy-based actuators offer distintive features that make them advantageous competitors to traditional electromechanical devices. The production of force and motion without contact is one of the most important features. However, the largely non-linear and hysteretic nature of the response of such materials makes them of little use apart from on-off or continuous actuation. In this work we present the results obtained in a laboratory prototype of linear position FSMA actuator, where the active element is a 12 mm long Ni-Mn-Ga single crystal. The crystal expands a maximum of 12 micrometers and in control experiments, is commanded to expand and contract alternatively to reach positions at 5 µm and 8 µm. It shows that the commanded position could be controlled within 20 nm.

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Development of a shape memory alloy multiple-point injector for chemotherapy

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1243/095441105x9354 ◽

2005 ◽

Vol 219 (3) ◽

pp. 213-217 ◽

Cited By ~ 4

Author(s):

W Xu ◽

T G Frank ◽

A Cuschieri

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Direct Injection ◽

Element Model ◽

Multiple Point ◽

Linear Elastic ◽

Outer Needle ◽

Non Linear ◽

Deformation Force ◽

Medical Needle

A medical needle is described that allows injection to take place at multiple sites through a single stab wound. This is achieved by extruding multiple, thin, and curved internal needles from a larger, straight, outer needle. The development and finite element modelling of the shape memory alloy (SMA) inner needles is presented in this paper. A non-linear elastic element model was used in this process to allow for the non-linear properties of the alloy and the large deformations that occur. The model provided maximum strain values and penetration forces for the inner needles. The deformation force on the tip of the needle was measured against displacement to confirm the predicted penetration force. Applications for the device include the treatment of liver cancer by direct injection of alcohol into the tumours.

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Morphing Laminar Wing With Flexible Extrados Powered by Shape Memory Alloy Actuators

Smart Materials, Adaptive Structures and Intelligent Systems, Volume 1 ◽

10.1115/smasis2008-377 ◽

2008 ◽

Cited By ~ 16

Author(s):

Vladimir Brailovski ◽

Patrick Terriault ◽

Daniel Coutu ◽

Thomas Georges ◽

Emeric Morellon ◽

...

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Structural Model ◽

Optimization Technique ◽

Laminated Composite ◽

Functional Requirements ◽

Morphing Wing ◽

Active Structure ◽

Finite Element Software ◽

Aerodynamic Performances

An active structure of a morphing wing designed for subsonic cruise flight conditions combines three principal subsystems: (1) flexible extrados, (2) rigid intrados and (3) an actuator group located inside the wing box. A structural model of the flexible extrados built with ANSYS finite element software is coupled with X’Foil fluid dynamics software to evaluate mechanical and aerodynamic performances of the morphing wing in different flight conditions. Using the multicriteria optimization technique, an active structure consisting of the 4-ply laminated composite flexible extrados powered by two individually controlled actuators is selected. Shape memory alloy (SMA) actuators are designed as power elements for the morphing wing. To meet the functional requirements of the application, the geometry of the SMA elements is calculated using the results of the constrained recovery testing of the selected material.

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