Several issues concerning the health monitoring of a carbon filament wound missile canister using inverse methods are investigated in this paper. A frequency response function model relating 36 different input forcing functions distributed across the canister to three mutually orthogonal acceleration responses was identified experimentally using modal impact testing. To create a more refined model while limiting the number of required experiments, the acquired frequency response functions were interpolated to generate new data at non-measured degrees of freedom on the canister. An iterative algorithm was developed to overcome the underdetermined nature of the force identification problem by utilizing the coupling inherent in the triaxial measurements. Over 99% of the trial impacts were correctly localized. The detection of cracks through nonlinear wave modulation spectroscopy was then investigated because, unlike the modal vibration response, modulation was shown to be largely unaffected by changes in the canister’s modal characteristics. Despite drastic changes in the canister’s operating environment, the use of multidirectional measurements made it possible to detect a crack using impact modulation.

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