Impact of nonlinear friction on frequency response function measurements

This paper discusses the impact of nonlinear friction on frequency response function (FRF) measurements of mechanical systems with nonlinear friction. Having an idea of the level of nonlinear distortion is valuable information for robust linear control design: it allows to estimate the level of accuracy of a linear approximation of the system under consideration. The impact of nonlinear distortions is measured using the multisine excitation approach presented in [5]. A linear approximation of the system and a reliable estimate of the level of systematic and stochastic nonlinear distortions are derived using a single special odd multisine excitation. This is shown by means of simulations of mechanical system with friction. The friction model is nonlinear and integrates sliding and presliding behaviour .status: publishe