Development of Active and Sensitive Structural Material Systems

This paper describes new concepts the author has proposed and demonstrated to realize metal and polymer based sensitive and/or active structural material systems suitable for smart structures. Most of the developments have been done by simple and innovative methods without using sophisticated and expensive sensors and actuators. The following topics are mainly examined: (1) forming optical interference and loss type strain sensors in epoxy matrix simply by embedding and breaking notched optical fiber in it; (2) forming a multifunctional sensor in aluminum matrix for temperature and strain monitorings by embedding an oxidized nickel fiber; (3) fabricating multifunctional composites by using conventional structural materials an active laminate of CFRP/aluminum of which unidirectional actuation is realized by electrical resistance heating of carbon fiber in the CFRP layer and its curvature change can be monitored using optical fiber multiply fractured in the CFRP layer.