Smart materials and Smart structures [civil]

A new generation of materials called smart materials is changing the way a structural system is going to be designed, built and monitored. Advances in composite materials, instrumentation and sensing technology (fiber-optic sensors) in combination with a new generation of actuator systems based on Piezoelectric ceramics and shape Memory Alloys have made this possible.

Shape memory alloys have found applications in a variety of high performance products, ranging from aircraft hydraulic coupling and electrical connectors to surgical suture anchors. Since the material can generate high actuation forces in response to temperature changes, shape memory alloys have the potential to serve as an alternative to solenoids, special significance in the area of smart structures because it offers significant advantages over conventional actuations technologies in number of ways.

• Large amounts of recoverable strains offer very high work densities. This is very attractive in situations where the work output to weight ration is critical.
• Direct actuation without moving part there by increasing the efficiency.
• Large available strains permits long strokes with constant force output.
• The actuation can be linear or rotatory.