"Intelligent structures" are designed to self monitor their ability to perform designed tasks. To provide this "intelligence" a nerve system must be embedded in the structure. Optical fiber strain sensors have repeatedly been touted as prime candidates for this nervous system, particularly when the structure is produced from fiber reinforced composite materials. Recent results indicate that the nervous system is not an uncoupled observer and that it may cause severe degradation of the structural component which they monitor. The amount of fiber- host material interaction is a critical, but overlooked, aspect of the fast emerging smart structures technology. The fiber-host material interaction is to be studied on three fronts. A high frequency moire' interferometry technique is proposed to study the surface strains in the fiber-host material interaction zone. Calculations indicate that this image processing based technique can increase the resolution of moire' interferometry as much as 800 fold. Optical fiber sensor technology will be advanced so that meaningful internal strain information can be obtained from embedded single mode optical fibers. Three dimensional finite element analysis will be used to design experiments and to supplement experimental results. The above information will be used both to quantify fiber-host material interaction mechanisms and to predict the effect these mechanisms have on the life cycle of a structural component containing an embedded optical fiber nervous system. The optical fiber-host material interaction mechanisms must be resolved before an overwhelming commitment to a structurally embedded optical fiber nervous system can be made.

Project Start
Project End
Budget Start
1989-07-01
Budget End
1991-12-31
Support Year
Fiscal Year
1989
Total Cost
$79,166
Indirect Cost
Name
University of Maryland College Park
Department
Type
DUNS #
City
College Park
State
MD
Country
United States
Zip Code
20742