Physical modeling with multipoles

Importance of physical modeling, also called ´virtual prototyping´, grows with the increasing power of computers as well as with the growing demands on control-system dynamics. The paper advocates for the multipole approach to physical modeling in contrast to the well-known bond-graph approach. As the topological representation of multipole models is isomorphic with the geometrical representation of the modeled real systems, these models can be easily set up based on mere inspection of the systems. The relationship between multipole and bond-graph approaches is explained using linear graphs. A definition of multiports as a mapping of the subsystem energetic interactions from the geometric onto the topological space is introduced. It is shown that it is the oversimplified representation of multiports what makes the bond graphs cumbersome and ambiguous.