SMART STRUCTURES

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Smart material systems and structures have been defined in various ways. It is intelligent, smart, adaptive and active based on dictionary meanings. Intelligent implies ability to use one’s existing knowledge to meet new situations and to solve new problems, whereas smart implies mental alertness or quickness of perception. They define a smart structure as a non-biological physical structure having,
i. A definite purpose
ii. Means and imperative to achieve that purpose.
iii. A biological pattern of functioning.
The integrated system with above mentioned attributes functions such that it imitates biological or living material i.e. it will be adaptable and use available energy as efficiently as possible. Thus, based on biological model, actuators can be seen as artificial muscles, sensors as artificial nerves and electronic controls as brain.
It is important to note that the biological definition does not define the type of materials to be utilized. It does not even state definitively that there are sensors, actuators and controls, but instead describes a philosophy of design.


3. USES OF SMART STRUCTURES
Before venturing into any field it is very important to know the benefits or returns of its use. Smartness makes “dumb” conventional structures, better than the rest because of the following reasons:
1. Increased performance: This is the most important reason why the smart structures find use. The changes in the system according to the changes in the external environment are nothing but optimization of a structure for increased efficiency and economy.
2. Reduced costs: For many systems the cost of purchase or manufacture is less than the cost of maintenance and operation e.g., structures like bridges. Continuous health monitoring and maintenance helps in minimizing the maintenance costs as compared to repairing a conventional structure that has reached its distress condition.
3. Increased safety: This feature is evident from the above point. There are some systems such that they find their use after a long period of their manufacturing. Such systems are unsafe to be used after a long time as their condition might have deteriorated. For example, military systems like war planes are used only during the wartimes.


4. POTENTIAL APPLICATION AREAS
One of the goals is to understand the important characteristics and thrust areas that make smart structures an active area of research.
1. Smart materials and structures are different from existing materials and structures because they have the means to sense their surrounding environment, process the information, and act in a controlled way to respond to the changing environment. Smart structures should be lighter in weight, consume less energy to manufacture and operate, and achieve higher performance levels than conventional structures. These systems are important because they have the ability to take advantage of the new advancing computer technologies and integrated sensor/actuators, and thereby contain some sense of intelligence, which enables better structural performance capabilities. The interaction between the sensors, actuators and the control system is an important research activity.