Modeling of Multibody Systems with the Object-oriented Modeling Language Dymola

The object-oriented modeling language Dymola allows the physical modeling of large interconnected systems based on model components from diierent engineering domains. It generates symbolic code for diierent target simulators. In this paper, a Dymola class library for the eecient generation of the equations of motion for multibody systems is presented. The library is based on an O(n) algorithm which is reformulated in an object-oriented way. This feature can also be interpreted as a bond graph oriented modeling of multibody systems. Furthermore a new algorithm for a certain class of variable structure multi-body systems, such as systems with Coulomb friction, is presented, which allows the generation of eecient symbolic code.