Force, displacement and strain nonlinear transfer function estimation

摘要

The analysis of surface strain, displacement and acceleration data from the nonlinear response of a beam under base excitation is performed using frequency domain based reverse path identification. The uncorrelated nonlinear contributions of the dynamic response are used as inputs to produce repeatable transfer function estimates with the applied base acceleration as the output. The two stage process of displacements to strain to applied base excitation is proposed and also investigated. System identification of the reverse transfer functions is shown to be reasonably successful in quantifying the main frequency dependent contributions which occur at and around the fundamental natural frequency and harmonics due to the geometrical nonlinearity present.