Dynamic Sampling for FOCUS Hybrid Components

The combination of embedded systems with physical components, termed Cyber-Physical Systems (CPSs), poses important challenges in the design, modelling, simulation and verification of systems, also why they combine discrete software elaborations with analogues time evolutions and different engineering disciplines. In this domain, the software part is increasing the dimension and has a more important role. An important formalism for describing continuous and discrete systems is the hybrid system formalism. We present our approach based on the Focus modelling theory to model hybrid systems, which have discrete transitions and continuous differential equations. The modular and logical structure of Focus components combined with hybrid systems improves the support for the modelling of CPSs. Anyway, a fully continuous simulation may be too complex and not represent the final hardware where the model will be deployed. Therefore, we propose two sampling techniques to transform the continuous time in discrete steps, in which the length of the sampling period it is dynamically changed.