Abstract:

The contact force of two impacting elastic bodies is widely modeled as the parallel combination of a nonlinear spring and a nonlinear dashpot.The restoring force of the nonlinear spring can be determined according to Hertzian contact law in elasticity, while the model and corresponding parameters of the nonlinear damping force have to be identified through experiments.The current approach of damping identification is based on the measured time histories of both contact force and relative approaching velocity of two impacting bodies.In this paper, a new technique is presented for the damping identification on the basis of the measured time history of the contact force alone.Hence, the tough problem of measuring the relative approaching velocity of two impacting bodies just before impact is removed.The efficacy test of the new technique is given in the paper through an example of identifying the impact damping of a pair of clamped beams.

Key words: Her tzian theor y, impact, damping, pa rameter identificat ion