Recent developments in applying smart structural materials

Abstract

Smart structures and materials are those that can sense external stimuli, via internal sensing and/or actuation, and then respond with active control to those stimuli in real or near-real time. Smart systems respond and adapt to changes in condition or environment by integrating the functions of sense, logic, action, and control, usually in a repetitive manner. This broad and strongly interdisciplinary field is still emerging. Current application areas include transport, civil engineering, medical hardware, and manufacturing technology. The interest is in applying capabilities to both existing and new structures. Current activities in the fi eld range from the design, fabrication, and test of fully integrated structural systems to enabling research in individual discipline areas such as materials, sensing and actuation techniques, control algorithms and architectures, and signal processing. Defense, energy, and electronics businesses are prime developers and markets for smart technology throughout the world. In the United States, large, recent efforts have been funded by various initiatives such as the U.S. Air Force Research Laboratory’s Intelligent Engine, the U.S. Department of Energy’s Smart Power Turbine, and the U.S. Defense Advanced Research Projects Agency’s (DARPA’s) Smart Materials and Structures Demonstration and Multifunctional Materials Programs. The value of applying smart materials in systems and structures greatly exceeds the cost of development and manufacture, as the articles in this issue will demonstrate. The diversity of material structures is immense: piezoelectric pressure transducers, shape-memoryalloy actuators, photochromic windows, and tunable electromagnetic absorbers. A typical approach to creating smart Recent Developments in Applying Smart Structural Materials