DYMORE: A Finite Element Based Tool for the Analysis of Nonlinear Flexible Multibody Systems

Multibody dynamics analysis was originally developed as a tool for modeling mechanisms with simple tree-like topologies composed of rigid bodies, but has considerably evolved to the point where it can handle nonlinear flexible systems with arbitrary topologies. It is now widely used as a fundamental design tool in many areas of mechanical engineering. In the automotive industry, for instance, multibody dynamics analysis is routinely used for optimizing vehicle ride qualities, a complex multidisciplinary task that involves the simulation of many different sub-components. Modern multibody codes can deal with complex mechanisms of arbitrary topologies including sensors, actuators and controls, are interfaced with CAD solid modeling programs that allow to directly import the problem geometry, and have sophisticated graphics, animation and post-processing features [1, 2, 3]. The success of multibody dynamics analysis tools stems from their flexibility: a given mechanism can be modeled by an idealization process that identifies the mechanism components from within a large library of elements implemented in the code. Each element provides a basic functional building block, for example a rigid or flexible member, a hinge, a motor, etc. Assembling the various elements, it is then possible to construct a mathematical description of the mechanism with the required level of accuracy. Multibody systems fall into the following broad categories