Stiffness NonLinearity Classification Through Structured Response Component Analysis Using Volterra Series
Abstract
Most nonlinear analysis problems, consider only the Duffing oscillator as a representative case. In engineering analysis, it is however, also important to recognise the type of nonlinearity actually influencing the system. A procedure, involving structured higherorder FRF analysis based on Volterra theory is suggested in the present work, to distinguish a polynomial form of nonlinearity from other possible forms. Volterra theory provides concepts of linear, bilinear, trilinear, etc. kernels, which upon convolution with the excitation force and subsequent summation can be employed to represent the response of a nonlinear system. The kernels of the system are understood as multidimensional unit impulse response functions. The Volterra series response representation is employed in this work to facilitate its processing in a structured manner, to extract characteristic features, which can help in placing the system nonlinearity in an appropriate class. The Volterra series platform is also employed to make a distinction between symmetric and asymmetric forms of the restoring force function. A multitone excitation procedure is further suggested, through which higherorder kernels of the system can be constructed for identification of the structure of the polynomial representing the restoring force. The procedures are illustrated through numerical simulation.
 Publication:

Mechanical Systems and Signal Processing
 Pub Date:
 March 2001
 DOI:
 10.1006/mssp.2000.1331
 Bibcode:
 2001MSSP...15..323C