A novel class of piezoelectric-based energy-harvesting power sources has been developed for gun-fired munitions
and similar high-G applications. The power sources are designed to harvest energy primarily from the firing acceleration,
but from in-flight vibratory motions as well. During the firing, a spring-mass element reacts to the axial acceleration,
deforming and storing mechanical potential energy. After the projectile has exited the muzzle, the spring-mass element
is free to vibrate, and the energy of the vibration is harvested using piezoelectric materials.
These piezoelectric-based devices have been shown to produce enough electrical energy for many applications such
as fuzing, and are able to eliminate the need for chemical batteries in many applications. When employed in fuzing
applications, the developed power sources have the added advantage of providing augmented safety, since the fuzing
electronics are powered only after the projectile has exited the muzzle and traveled a safe distance from the weapon
platform.
An overview of the development of these novel power sources is provided, especially designing and packaging for
the high-G environment. Extensive laboratory and field testing has been performed on various prototypes; the methods
and results of these experiments are presented. In addition to presenting the development and validation of this
technology, methods for integrating the generators into different classes of projectiles are discussed along with strategies
for manufacturing. This technology is currently validated to the extent that prototype devices have been successfully
fired on-board actual gun-fired projectiles, demonstrating survivability and indicating performance. Strategies for
designing the devices for a particular round and transitioning to commercialization are also discussed.
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