Challenges in physical modeling for adaptation of cyber-physical systems

Cyber-physical systems (CPSs) mix software, hardware, and physical aspects with equal importance. Typically, the use of models of such systems during run time has concentrated only on managing and controlling the cyber (software) aspects. However, to fully realize the goals of a CPS, physical models too have to be treated as first-class models. This approach gives rise to three main challenges: (a) identifying and integrating physical and software models with different characteristics and semantics; (b) obtaining instances of physical models at a suitable level of abstraction for adaptation; and (c) using and adapting physical models to control CPSs. In this position paper, we elaborate on these three challenges and describe our vision of making physical models first-class entities in adaptation. We illustrate this vision in the context of power adaptation for a service robotic system.