**Acknowledgements**

*3.8.3 Microelectronic mechanical systems (MEMS)*

*Multifunctional Ferroelectric Materials*

**3.9 Piezoelectricity in defense applications**

possible, in part, by using piezoelectric actuators.

*3.8.4 Tennis racquets*

*3.9.1 Micro robotics*

*3.9.2 Course-changing bullets*

**Figure 12.**

**86**

*Piezoelectric micro robotics.*

such a feat, piezoelectric actuators and sensors are often used.

MEMS devices have become more commonplace as more integrated capabilities are required in smaller packages, such as cell phones, tablet computers, etc. The advantage of MEMS devices is that gyroscopes, accelerometers, and inertial measuring devices can be integrated into chip-sized packages. In order to accomplish

A somewhat unusual application for piezoelectricity integrates piezoelectric fibers into the throat of a tennis racquet along with a microcontroller in the handle. When the tennis player strikes the ball, the racquet frame deflects and generates an electric output that is boosted, reversed, and fed back into the fibers [14]. This is an

The piezoelectricity is used in Defense field for a variety of applications, they are:

In the field of small robotics, small power-efficient mechanical actuators and sensors are needed. With the use of piezoelectric actuators, building something as small as a robotic fly that can crawl and fly is technically feasible. In fact, a new field of robotic technology known as Micro Air Vehicles aims to build small drones the size of insects or birds that fly using flapping wings (**Figure 12**). They control surfaces just as birds and insects do. These types of feats in miniaturization are

Recently, DARPA invented a.50-caliber bullet that can change course in midflight. As absurd as this innovation may sound to some readers, the bullet uses an optical sensor that is mounted on its nose in conjunction with a control system and moveable tail fins to steer itself toward a laser-illuminated target. Although DARPA

attempt to cause destructive interference and dampen structural vibration.

I sincerely express my heartfelt gratitude and appreciation to my supervisors Dr. P.S.V.Subba Rao & Dr.B.Parvatheeswara Rao, Department of Physics, Andhra University for their supervision and guidance during the whole duration of my research. I am greatly indebted to my dear parents, family members and my wife Mrs. Niranjani Divya Revu for their constant motivation, inspiration, love and affection, It is my pleasure to acknowledge my colleagues, Finally, I express my sincere thanks to AUTHOURITIES of Vignan Group of Institutions, for his cooperation in extending me the necessary facilities to carry out my research work.
