We were honored to have Tim Hunter from Wolf Star Technologies present at the 2026 SIMULIA Americas Users Conference in Novi, Michigan, May 13-14, 2026.

Abstract: 

The use of finite element analysis is widely prevalent for the analysis of structural dynamics of complex systems [1]. A common approach in such analysis is the calculation of transient response using a modal superposition methodology that primarily relies on the eigenmodes of the structure. Typically, several changes are made in the early design iterations until all functional and performance requirements are satisfied by a design engineering team. While the design changes are being made, it can be very time consuming to run an updated finite element analysis (FEA) eigenmode and transient response for each design iteration that may require repeated meshing and multiple checks for convergence. Furthermore, subsequent design changes will not be able to use the modal participation factors from the transient response of the previous design. This study proposes a methodology that utilizes equivalent static mode condensation [2] to estimate the dynamic response of a system by leveraging previously calculated modal participation factors. Such an approach does not require a new eigenmode and transient response solution for every design iteration. The proposed approach is demonstrated through two examples – one for a beam with varying sizes of holes and slots and another one for a small tractor frame structure with several small and significant design changes. As can be observed from the results, very good correlation is seen for incremental but significant changes of design iterations. Even with relatively large design changes, it is observed that the structural response from the equivalent static mode condensation yields comparable results. The methodology proposed in this study is expected to yield a reasonable estimation as long as the boundary conditions do not change during multiple stages of the design iterations during initial phases of design. The primary benefit of this approach is a significant reduction in computation time and an overall reduction of the product development time. Similar approaches can be seen from other studies in the existing literature [3].

[1] Roy, D., Rao, G. V., Elements of Structural Dynamics: A New Perspective, Wiley, 2012.
[2] Cammarata, A., Sinatra, R., Maddio, P. D., Static condensation method for the reduced dynamic modelling of mechanisms and structures, Archive of Applied Mechanics, 89, 2033-2051, 2019.
[3] Franke, M., Krause, T. J., Wagner, M., Data-driven model order reduction with surrogate elements for transient simulations, Engineering Computations, 1-26, 2025.

 

Presenter: 

Tim Hunter

President - Wolf Star Technologies

Tim is the founder of Wolf Star Technologies, an engineering consulting and software development firm which concentrates on the efficient usage of FEA for engineering problems. Tim brings 40+ years of product development experience to his client's projects and innovative software platform, True-Load.

Tim earned a Bachelor’s degree in mechanical engineering from Marquette University and a Master’s and Ph.D. in engineering mechanics from UW-Milwaukee.

Tim enjoys spending time with his family. Tim has recently moved to be closer to his granddaughter in Minnesota. In his leisure time, Tim enjoys camping and hiking with his wife and their dog Lilo