Type of Document Master's Thesis Author Lenahan, Kristie M. URN etd-10012008-063036 Title Thermoelastic control of adaptive composites for aerospace applications using embedded nitinol actuators Degree Master of Science Department Electrical Engineering Advisory Committee
Advisor Name Title No Advisors Found Keywords
- aerospace structures
- shape memory alloy elements
Date of Defense 1996-05-05 Availability restricted Abstract
Aerospace structures have stringent pointing and shape control requirements during long-term exposure to a hostile environment with no scheduled maintenance. This makes them excellent candidates for a smart structures approach as current passive techniques prove insufficient. This study investigates the feasibility of providing autonomous dimensional control to aerospace structures by embedding shape memory alloy elements inside composite structures. Increasing volume fractions of nitinol wire were embedded in cross-ply graphite/ epoxy composite panels. The potential of this approach was evaluated by measuring the change in longitudinal strain with increasing temperature and volume fraction. Reduction of thermal expansion is demonstrated and related to embedded volume fraction.
Classical lamination theory is used to formulate a two-dimensional model which included the adaptive properties of the embedded nitinol. The model was used to predict the increased modulus and reduction of thermal strain in the modified plates which was verified by the experimental data.
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