What is an FMU?

The Functional Mock-up Interface (FMI) is a simulation standard for modeling complex cyber-physical systems (CPS). The FMI links together Function Mock-up Units (FMUs), each representing a distinct system component.

For example, to model a car’s tire + suspension system you could construct suspension.fmu and link it with tire.fmu. By linking these two components, changes in the state of one system is immediately transferred to the other system through appropriate coupling equations.

Thus with FMU we are able to build digital simulations by composing FMUs together in much the same that we build physical products by composing parts together.