Detecting Parametric Changes In Structures Using Resonant Chaos
Free (open access)
I.B. Schwartz & I. Triandaf
We present a technique for the detection of small adiabatic parameter changes in continuum mechanical structures. The technique relies on inducing chaos in general structures via an external oscillator, and measuring an appropriate time series in controlled and changed states. By exciting chaos at resonance, the dynamics naturally samples the structure at many wavelengths, and affords an excellent diagnostic tool for the detection of structural changes prior to damage onset. By using an embedding theory of time series, full phase space pictures resulting from changes in internal as well as external parameters may be detected. Two techniques are presented for comparison: A model based approach to detection, and a fully realizable time series method of detection. The theory behind the methods will be sketched, and illustrated with examples from continuum mechanics.