Two-port modeling and simulation of an electrodynamic shaker for virtual shaker testing applications

This article discusses the modeling and simulation of the coupling problem in virtual shaker testing applications. An innovative model of the electrodynamic exciter is developed based on a transmission line approach and a two-port network over Z-modeling is presented. The exciter is modeled by a two degrees of freedom mechanical structure coupled to an electrodynamic transducer. While classical lumped modeling depends on the structure under test, this enhanced model is totally independent and only relies on the physical parameters of the shaker which can be identified by non-linear curve fitting. The presented model is also shown to be partially decoupled, allowing an improved identification of the system. The validity and limitations are verified by comparison with experimental results and the developed model efficiently predicts the output reaction of the shaker as well as the prevailing coupling in the interface.