SPECTRAL RESPONSE OF ASYMMETRICAL RANDOM OSCILLATORS

An analytical procedure to estimate the power spectral density (PSD) r esponse of a weakly damped oscillator with a nonlinear asymmetrical re storing force under external stochastic wide-band excitation is presen ted. An equivalent linear system with random parameters is derived, fr om which the PSD is deduced. The use of corrective terms yields an app roximation of the PSD in the region of the second and third harmonic r esonant frequencies (as well as at higher harmonics). In the same way, the PSD of the reaction force is also reported. The method is applied to an impact oscillator with asymmetrical clearances and asymmetrical elastic stops.