A FEM Formulation for flexible multi-body system dynamic analysis

A simple engineering language is used to present a geometrical non-linear formulation based on position description. Velocity, acceleration and strain are achieved directly from nodal position, not displacements. The proposed methodology is based on the minimum potential energy theorem. A non-dimensional space is created and the relative curvature and fibers length are calculated for both reference and deformed configurations and used to directly compute the strain energy at general points. Damping is introduced into the mechanical system by a rheonomic energy functional. The final formulation is shown simplifying the understanding and the implementation of large deflection analysis when compared with typical FEM formulations.