The chapter describes IRM, a method that guides the design of smart-cyber physical systems that are built according to the autonomic service-component paradigm. IRM is a requirements-oriented design method that focuses on distributed collaboration.
It relies on the invariant concept to model both high-level system goals and low-level software obligations. In IRM, high-level invariants are iteratively decomposed into more specific sub-invariants up to the level that they can be operationalized by autonomous components and component collaborations (ensembles).
We present the main concepts behind the method, as well the main decomposition patterns that back up the design process, and illustrate them in the ASCENS e-mobility case study.