Smart Materials, Structures, and Mathematical Issues for Active Damage Control

Authors: Daniel J. Inman; Harley H. Cudney; VIRGINIA POLYTECHNIC INST AND STATE UNIV BLACKSBURG CENTER FOR INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES

Abstract:

The three objectives of this research were to study and create new technologies for: (1) identifying damage in complex structures; (2) mitigating damage in structures built from composite materials; and (3) controlling smart material systems and structures. Model independent, nondestructive evaluation methods for complex structures have been developed to detect incipient damage, delaminations and disbondments, and to allow structures to perform self- diagnostics. A patent has been granted for a method improving the impact tolerance and penetration resistance of composites. Several new technologies were developed to control smart material systems and structures. A compact actuator, producing both large displacements and forces, was designed, built, and tested for helicopter vibration and noise control. A theoretical model of wave propagation and energy dissipation in joints was developed. A new signal processing technique was developed for arrays of sensors to directly create a signal for the modal content of the structural vibration. A method of damage detection for complex structures that does not depend on an analytical model of the structure has been developed and experimentally verified.

Limitations:

APPROVED FOR PUBLIC RELEASE