FModal: A Flexible Body Dynamics Modeling Pipeline for Guidance and Control

This article describes the FModal tool that has been designed to bridge the gap between the structural dynamics and guidance and control domains to facilitate the development and use of high-fidelity flexible body dynamics models. FModal streamlines the process of generating modal data-including residual vectors and modal integral terms-from component NASTRAN structural dynamics models. The data generation process can be tailored to meet simulation fidelity and performance needs. FModal's output is a portable HDF5 file with hierarchical, well-organized, and labeled data that can be used to automate, simplify, and speed up the creation of flexible multi-body dynamics models-resulting in faster design iterations and reduced costs. This paper uses an interface between FModal and the DARTS flexible multibody dynamics tool to carry out several numerical studies to exercise and validate the FModal pipeline.