Virtual prototyping in modern vehicle development relies mainly on detailed and versatile vehicle models, which are usually built up as rigid body models. These models are used in many fields within vehicle development, for example for driver-in-the-loop simulations or in test benches for electronic control units. With increasing use of lightweight structures and higher demand on structural stiffness, structural flexibilities may no longer be negligible. Hence realtime capable vehicle models including structural flexibilities are becoming increasingly important. Time integration of flexible multibody systems require a large-scale system of differential-algebraic equations to be solved. This is performed with a partitioned linear-implicit Euler solver, using an index-2 formulation with constraint stabilization and the floating frame of reference approach. Various options to improve time integration performance are reviewed in this work. In addition the reduction process of flexible bodies, which is based on a constraint mode analysis, is evaluated to remove unnecessary modes and reduce model size.
