Free Planar Motion of Flexible Beams in MBS - A Comparison of Models

摘要

Two approaches for the description of free planar motion of elastic beam structures are studied: a method using redundant coordinate sets to maintain a moving frame of reference (MFR) discretization in a finite element formulation and the absolute nodal coordinate formulation (ANCF). Both are treated within the modern framework for multi-body systems including bi- and unilateral constraints as well as non-smooth dynamics. Numerical efficiency and accuracy of the models are investigated using two examples: A slider-crank mechanism with a flexible beam is used to study computational cost and the convergence for finer spatial discretizations. Non-smooth dynamics is studied for an elastic rocking rod built of an elastic beam bouncing on two fixed point obstacles.