Identification of nth-power velocity damping

This paper demonstrates how the two damping parameters associated with the non-linear nth-power velocity model can be identified from the time series records of the displacement and velocity responses to sinusoidal excitation. No restriction is imposed on the level of damping present and estimates are acquired by minimizing the square of the error between observed responses and those predicted by a linearized model. The problems of noise contamination and uncertain initial conditions are treated by using simulated data and converged estimates are presented with computation times measured in CPU seconds on a VAX 11780 computer.