  The concept of the Digital Twin, which in the context of this paper is the
virtual representation of a production system or its components, can be used as
a "digital playground" to master the increasing complexity of these assets.
Central subcomponents of the Digital Twin are behavior models that can provide
benefits over the entire machine life cycle. However, the creation, adaption
and use of behavior models throughout the machine life cycle is very
time-consuming, which is why approaches to improve the cost-benefit ratio are
needed. Furthermore, there is a lack of specific use cases that illustrate the
application and added benefit of behavior models over the machine life cycle,
which is why the universal application of behavior models in industry is still
lacking compared to research. This paper first presents the fundamentals,
challenges and related work on Digital Twins and behavior models in the context
of the machine life cycle. Then, concepts for low-effort creation and automatic
adaption of Digital Twins are presented, with a focus on behavior models.
Finally, the aforementioned gap between research and industry is addressed by
demonstrating various realized use cases over the machine life cycle, in which
the advantages as well as the application of behavior models in the different
life phases are shown.
