Research focus on experimental dynamic substructuring has grown in recent years in both academic and industrial interests. Progress continues for both component mode synthesis and frequency based substructuring methods with a heightened interest around the nonlinearities that come about in interfaces often found in dynamic substructuring examples. Many examples of substructuring decouple structures at the interface where sources of nonlinear damping and stiffness may occur, and some, like the transmission simulator method, instead mass-load the interface. A clear path to incorporate these interface nonlinearities is a true challenge for the substructuring community.
In recent years, the Society of Experimental Mechanics’ (SEM’s) Technical Division on Dynamic Substructuring recognized a need for a simple yet challenging benchmark structure for experimental-analytical substructuring collaborations as compared to previous benchmark structures (Mayes, An introduction to the SEM substructures focus group test bed – The Ampair 600 Wind Turbine. In topics in experimental dynamics substructuring & wind turbine dynamics, Jacksonville, FL, 2012; Harvie and Avitable, Comparison of some wind turbine blade tests in various configurations. In Proceedings from the 30th International Modal Analysis Conference, Orlando, FL, 2012; Roettgen and Mayes, Ampair 600 wind turbine 3-bladed assembly substructuring using the transmission simulator method. In Proceedings from the XXXIII IMAC Conference, Orlando, FL, 2015). A team with members from many research institutes set out from several desirable properties and a unit-frame structure was designed as a benchmark for current collaborative efforts detailed in (Roettgen and Linderholt, Planning of a black-box benchmark structure for dynamic substructuring. In International Modal Analysis Conference 37, 2019). The benchmark structure is built up by a frame with threaded inserts that is bolted to plates of varying thickness and materials. When assembled, this structure can span a diverse application space of substructuring techniques. Previous endeavors with this benchmark have been focused on testing different methods of linear substructuring as well as collaborating in the development of different methods. The next steps in this challenge aim to direct the community at different nonlinear substructuring challenges that can be studied using the four-unit frame from the benchmark structure. This abstract highlights three potential nonlinear adaptations of the benchmark structure, where drawings and data for these options will be made available on the dynamic substructuring Wiki prior to the IMAC conference.
