Monday  |  Salon 8  |  05:30 PM–05:50 PM

#16751–Impedance to Modal Substructuring: Experimental Applications

Dynamic substructuring involves estimating the dynamics of a system assembly using the dynamics pertaining to a system’s individual, uncoupled components. Current methods of dynamic substructuring allow for the direct coupling of physical models, modal models, physical to modal models, and impedance models; Until recently, a method directly coupling an impedance model to a modal model had not been addressed. The direct Impedance to Modal Substructuring technique was developed to expand the types of models that may be coupled directly without the need for additional calculations. Previous work derives and validates the Impedance to Modal Substructuring technique in an analytical sense. The Impedance to Modal Substructuring technique has not yet been validated in an experimental environment.

In this work, the Impedance to Modal Substructuring approach was validated using experimentally derived models of the BARC Box and the Four Bay Frame. The Box and Frame structures, both part of the dynamic substructuring group’s round robin test fixtures, were defined as the impedance and modal model respectively. The Impedance to Modal Substructuring approach was used to directly couple the experimentally derived impedance and modal models of the Box and Frame structures, respectively. The Impedance to Modal Substructuring results were compared to a like Frequency Based Substructuring system model as well as measurements acquired from the physically assembled Box and Frame structures. A variety of multi-directional references and responses on the Box and Frame assembly were used to experimentally validate the Impedance to Modal Substructuring technique.

John Seymour   University of Massachusetts at Lowell
Peter Avitabile   University of Massachusetts at Lowell
Ray Joshua   Honeywell