Experimental Analysis of a Softening-Hardening Nonlinear Oscillator Using Control-Based Continuation

摘要

Control-based continuation is a recently-developed approach for testing nonlinear dynamic systems in a controlled manner and exploring their dynamic features as system parameters are varied. In this paper, control-based continuation is used to track directly in the experiment the steady-state periodic solutions of a single-degree-of-freedom oscillator presenting a softening-hardening restoring force. The oscillator forced response is investigated and fully characterized in forcing amplitude and frequency. The oscillator's backbone curve is then extracted directly in the experiment by following a phase quadrature condition between the oscillator response and the base excitation.