NASA 1999 SBIR Phase I


PROPOSAL NUMBER 99-1 05.04-4943 (Chron: 992025 )

PROJECT TITLE

Biomimetics Based Design of Damage Tolerant Airframe Panels


TECHNICAL ABSTRACT (LIMIT 200 WORDS)

The specific innovation proposed is to design an advanced composite airframe panel for damage tolerance by incorporating biologic solutions to a similar problem found in nature, using a biomimetic approach. We will identify principal material (fiber) directions and density profiles about naturally occurring holes in bones through a microscopic and radiographic techniques. These holes are known to be damage tolerant, as they clinically do not represent a fracture or fatigue failure initiation site. In addition to its novel microstructure, bone is also a 2 "fiber" composite material, consisting of stiff bone mineral crystals embedded in a scaffold of compliant collagen fibers.

We will demonstrate the expected low stress concentrations about the hole through mechanical testing and moiré interferometry. We will then incorporate these principal material directions and density and use a 2 fiber system in a computational model of a representative airframe panel. This model will be used to demonstrate the advantages of biomimetic design. We believe biomimetic design principles can be used to reduce aircraft weight, as bones are weight optimized due to the energy expenditure required to carry such a relatively heavy tissue. Furthermore, by increasing damage tolerance, life cycle costs of airframes can be reduced significantly.


POTENTIAL COMMERCIAL APPLICATIONS

We expect a varied set of commercial applications for the design software we hope to prove feasible in this Phase I effort and develop in a Phase II effort. The natural consumers for such software are private contractors and government agencies involved in regulating, deploying, and servicing composite airframes. These users will be able to use the developed software in the primary design of structures and in the design of composite repairs as well.

We envision another group of consumers to be bioengineers and clinicians involved in constructing tissue engineered repairs for treating fractures and surgically created holes in bones.


NAME AND ADDRESS OF PRINCIPAL INVESTIGATOR (Name, Organization Name, Mail Address,

City/State/Zip)

Shao-Chun (Tony) Liu

AeroChem Corporation

PO Box 90087

Gainesville , FL 32607 - 0087


NAME AND ADDRESS OF OFFEROR (Firm Name, Mail Address, City/State/Zip)

Aerochem Corporation

PO Box 90087

Gainesville , FL 32607 - 0087