Modeling of the youBot in a serial link structure using twists and wrenches in a bond graph

We present a walk-through tutorial on the modeling of a complex robotic system, like the newly developed desktop mobile manipulator youBot developed by KUKA[5, 4]. The tutorial shows the design of models for typical robotic elements, done in a reusable object-oriented style. We employ an energy-based approach for modeling and its bondgraph notation to ensure encapsulation of functionality, extendability and reusability of each element of the model. The kinematic representation of mechanical elements is captured using screw theory. The modeling process is explained in two steps: first submodels of separate components are elaborated and next the model is constructed from these components.