- System designer contract how to#
- System designer contract verification#
- System designer contract software#
We have also showed how we can reason on functioning modes in our framework.Ī general, compositional, and component-based contract theory is proposed for modeling and specifying heterogeneous systems, characterized by consisting of parts from different domains, e.g. if the execution period of a controller is small enough to effectively regulate the continuous behavior. We have proposed a methodology to reason on temporal properties, e.g. From this result, we have developed several tools to help for the modular reasoning on cyber-physical systems. The resulting system is correct-by-construction. Then, at each stage of the design, we can verify that the desired properties are still guaranteed. We are able to modularly model cyber-physical systems, but also prove their correct functioning. Our main contribution is the development of such approach in Differential Dynamic Logic. It is possible to obtain a proof of the correct functioning of industrial systems with a reduced proof effort. Thus, the proof effort is reported to elementary components. We have then to ensure that the properties are preserved through the composition. This step can be done by a domain expert, but also by a computer program if the component is of a reasonable size. To achieve it, we associate to each component properties on its inputs and outputs, then prove that they are satisfied. We have to make the proof compositional too. But this approach does not solve the problem of the proof of correct functioning of the system.
The main advantage of this method is that it corresponds to the work-flow in the industry : consider each elements separately and compose them later. A water-plant will thus be obtained by the composition of several water-tanks.
We obtain the complete system by assembling the different components. Each component correspond to a subsystem of the final system and are easier to model due to their reasonable size. Rather than modeling it in one block, we model it pieces by pieces, called components. Our approach is to model the system in a compositional manner. And once this modeling done, how guaranteeing the correct functioning of such systems.
System designer contract how to#
Our problematic is how to efficiently model cyber-physical systems where the complexity lies in a repetition of elementary blocks. The system under consideration is modeled in one block.
System designer contract verification#
Recent works have allowed significant progress in the domain of the verification of cyber-physical systems, but the approach is still monolithic. that the cruise-controller does not allow the vehicle to exceed the speed limit. Formal methods is a set of mathematical methods that are used to guarantee that a system behaves as expected, e.g. It is mandatory to develop methods to ensure the correct functioning of such systems. a design error which leads to an unexpected behavior can harm humans. Numerous of such systems are safety-critical, i.e. the velocity of a vehicle, and discrete behaviors, e.g. Contracts for System Design illustrates the use of contracts with two examples: requirement engineering for a parking garage management, and the development of contracts for timing and scheduling in the context of the AUTOSAR methodology in use in the automotive sector.Ĭyber-physical systems mix continuous physical behaviors, e.g.
System designer contract software#
It encompasses contracts for both software and systems, with emphasis on the latter. This meta-theory provides deep and illuminating links with existing contract and interface theories, as well as guidelines for designing new theories. It identifies the essence of complex system design using contracts through a mathematical “meta-theory”, where all the properties of the methodology are derived from a very abstract and generic notion of contract. Contracts for System Design provides such a treatment where contracts are precisely defined and characterized so that they can be used in design methodologies with no ambiguity. Several results have been obtained in this domain but a unified treatment of the topic that can help put contract-based design in perspective has been missing. Contract-based design provides a rigorous scaffolding for verification, analysis, abstraction/refinement, and even synthesis. Recently, contract-based design has been proposed as an “orthogonal” approach that complements system design methodologies proposed so far to cope with the complexity of system design.