Abstract :
[en] Today, state-of-the-art simulation packages in flexible multibody dynamics allow the high-fidelity analysis of industrial mechanisms and machines in many application fields including robotics, automotive systems, aeronautics, deployable structures or wind turbines. However, some classes of problems still remain difficult to solve in flexible multibody dynamics, such as problems with unilateral contact conditions as well as control and optimization problems. These problems motivate the development of innovative finite element (FE) formulations which are under study in our research group. This talk will present an overview of these activities and will be composed of two parts.
In the first part, we will introduce a local frame FE formulation for flexible multibody systems, which is based on the theory of differential-geometry and Lie groups. This framework significantly simplifies the development of the finite element library, the implementation of semi-analytical methods for sensitivity analysis, the solution of inverse dynamics problems for robot control design and the design optimization of structural components.
The second part will address the simulation of flexible systems with contact conditions as encountered, e.g., in mechanical transmissions. We propose an extension of the nonsmooth contact dynamics method to systems with flexible bodies. Accordingly, the unilateral constraints (as well as the bilateral constraints) are enforced exactly at position and velocity levels. Thus, the method differs significantly from penalty techniques since no penetration is allowed. Applications are under development in vehicle dynamics, wind turbines and tamping machines for railway tracks.
