  An integrated and automated smart structures approach for structural health
monitoring is presented, utilizing an array of piezoelectric transducers
attached to or embedded within the structure for both actuation and sensing.
The system actively interrogates the structure via broadband excitation of
multiple actuators across a desired frequency range. The structure's vibration
signature is then characterized by computing the transfer functions between
each actuator/sensor pair, and compared to the baseline signature. Experimental
results applying the system to local area damage detection in a MD Explorer
rotorcraft composite flexbeam are presented.
