Damping of Structural Vibrations Using Adaptive Joint Connections and Neural Control
In the present paper, a concept for vibration suppression of flexible structures based on controlled energy dissipation in adaptive joint connections is presented. First, the damping effect of dry friction on the dynamical behaviour of a two-dimensional truss structure consisting of five struts and one bolted joint connection is investigated experimentally and numerically. Experiments are carried out with varied normal force in the bolted joint in order to analyse the influence on the vibration characteristics of the flexible structure. For the experimental structure a FE formulation is presented including a model of the frictional joint connection. Finally, a neural control approach for the adaptive joint connections is described. An application example illustrates this so-called semi-active vibration damping concept.
The present paper shows that this concept significantly enhances the vibration suppression of a flexible lightweight structure. Based on these results. an adaptive three-dimensional large space structure with adaptive joints is in reach in the near future.
KeywordsNormal Force Truss Structure Vibration Suppression Neural Controller Active Vibration Control
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