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SPACE is a model-driven engineering technique for reactive distributed systems. It enables to develop system models from reusable building blocks, formal analysis by model checking as well as automated transformation to executable code. In this paper, we describe an extension of the SPACE formalism which allows to model and verify also real-time behavior. In particular, one specifies real-time constraints in the interface descriptions of the building blocks, so-called Real-Time External State-Machines (RTESMs). The RTESMs are translated to guards, clocks and invariants of Timed Automata which can be analyzed by means of the model checker UPPAAL. The approach is explained by a component protecting an electrical motor controller system against overspeed. In particular, we prove that by keeping certain maximum response times, this system guarantees that the speed of the motor stays within certain limits.

Using probabilities in the formal-methods-based development of safety-critical software has quickened interests in academia and industry. We address this area by our model-driven engineering method for reactive systems SPACE and its tool-set Reactive Blocks that provide an extension to support the modeling and verification of real-time behaviors. The approach facilitates the composition of system models from reusable building blocks as well as the verification of functional and real-time properties and the automatic generation of Java code. In this paper, we describe the extension of the tool-set to enable the modeling and verification of probabilistic real-time system behavior with the focus on spatial properties that ensure system safety. In particular, we incorporate descriptions of probabilistic behavior into our Reactive Blocks models and integrate the model checker PRISM which allows to verify that a real-time system satisfies certain safety properties with a given probability. Moreover, we consider the spatial implication of probabilistic system specifications by integrating the spatial verification tool BeSpaceD and give an automatic approach to translate system specifications to the input languages of PRISM and BeSpaceD. The approach is highlighted by an example.Comment: In Proceedings FESCA 2014, arXiv:1404.043

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A method preserving cyber-physical systems to operate safely in a joint physical space is presented. It comprises the model-based development of the control software and simulators for the continuous physical environment as well as proving the models for spatial and real-time properties. The corresponding toolchain is based on the model-based engineering tool Reactive Blocks and the spatial model checker BeSpaceD. The real-time constraints to be kept by the controller are proven using the model checker UPPAAL.