Development of a morphing helicopter blade with electrochemical actuators

The use of the expansion of electrochemical cells, upon ion intercalation, for the development of a morphing helicopter blade is explored. Using commercially available lithium-ion batteries as demostrators of the technology, two actuator prototypes suitable for the application are developed. The first prototype consists of a weave of fibers enclosing an array of cells in such a way that the thru-thickness expansion of the cells is transformed into an in-plane contraction. A mathematical model of the actuator is developed and used for the prototype design, which is then implemented using three cells and steel wires. Tests performed on the prototype show that, after accounting for viscoelastic phenomena, the prototype free strain agrees well with the model predictions. A Blade Element Momentum Theory model of the helicopter rotor, used for the design of the second actuator prototype, is described. The model is used for evaluating a morphing scheme in which the blade deforms its trailing edge by different amounts along the span. Under this scheme, a suitable blade twist in terms of forward flight performance can be selected, and the trailing edge deflection is then used to improve the performance in hover.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Mechanical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Tubilla Kuri, Fernando

Advisor dc:contributor.advisor

• Steven Ray Hall.

• Mechanical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/38933

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/38933