Instrumented Projectiles for Measuring Impact Forces to Characterize Ballistic Behavior of Fabrics and Composites

Due to the complex wave propagation and vibration involved in dynamic loading, commonly used sensors, such as electrical resistance strain gauge and accelerometer, cannot adequately measure the true loading history without a specially designed mechanism. In the Phase I study, an innovative mechanism was successfully designed, constructed and proved to be able to recover the strain wave history caused by ballistic impact. A microprocessor was also designed and built for recording and processing the strain wave signals. Combining the innovative wave recovering mechanism and the microprocessor with a battery and a protection gear, an instrumented projectile was completed. In order to validate the accuracy of the instrumented projectile, a special facility was also designed and constructed. Experimental studies successfully demonstrated the capability and accuracy of the instrumented projectile in recording impact-induced force histories. In the Phase II study, it is required to refine the instrumented projectile for more advanced applications. For example, instrumented projectiles with smaller diameter and higher impact velocity are necessary to simulate the harsh environments encountered by the small arm projectiles used in military"s operations. In order to meet these requirements, additional considerations, such as wireless transmission and non-stand-alone designs will also be explored.