Semi-active control of friction dampers

Quite a few papers have appeared dealing with how to minimize the effects of friction in machines. A recurring theme has been that friction is a dynamic phenomenon. As such, much attention has been paid to obtaining the appropriate friction model structure, and to the identification of model parameters. For semi-active damping, friction dampers hold promise in many applications. In comparison to work on machine control, the desire here is to maximize the damping achieved by friction. In this paper, local control laws based on friction models with and without velocity dynamics are compared to reveal under what conditions detailed knowledge of friction is needed