An Approach Combining Simulation and Verification for SysML using SystemC and Uppaal

International audienceEnsuring the correction of heterogeneous and complex systems is an essential stage in the process of engineering systems.In this paper we propose a methodology to verify and validate complex systems specified with SysML language using a combination of the two techniques of simulation and verification. We translate SysML specifications into SystemC models to validate the designed systems by simulation, then we propose to verify the derived SystemC models by using the Uppaal model checker. A case study is presented to demonstrate the effectiveness of our approach

DesyreML: a SysML profile for heterogeneous embedded systems

International audienceWe propose a novel language for the formal description of heterogeneous embedded systems (DesyreML). As the main contribution, the language is formally described in terms of semantics and concrete syntax based on the SysML language. We define the concept of thick connector to allow for heterogeneous components communication and computation for multiple semantic domains (synchronous reactive, continuous time, discrete time, discrete-event). As technological application, a verification flow based on model-transformation techniques is described showing the use of an enriched version of the SystemC-AMS simulation kernel that is capable of simulating heterogeneous systems containing combinatorial loops. Finally, the language and the analysis flow are applied to a cruise control case study

Mapping SysML to modelica to validate wireless sensor networks non-functional requirements

International audienceWireless Sensor Networks (WSN) have registered a large success in the scientific and industrial communities for their broad application domains. Furthermore, the WSN specification is a complex task considering to their distributed and embedded nature and the strong interactions between their hardware and software parts. Moreover, most of approaches use semi-formal methods to design systems and generally simulation to validate their properties in order to produce models without errors and conform to the system specifications. In this context, we propose a Model Driven Architecture (MDA) approach to improve the verification of the WSN properties. This approach combines the advantages of the System Modeling Language (SysML) and the Modelica language which promote the reusability and improve the development process. In this work, we specify a model transformation from SysML static, dynamic and requirement diagrams to their corresponding elements in Modelica. Thanks to the SysML requirement diagram which is transformed into Modelica properties (constraints), we propose a technique using dynamic tests to verify WSN properties. We have used the Topcased platform to implement our approach 1 and chosen a crossroads monitoring system which is based on wireless sensors to illustrate it. Besides, we have verified and validated some wireless sensors properties of the studied system

Modeling of Hardware and Software for specifying Hardware Abstraction Layers

International audienceIn this paper we describe a practical approach for modeling low level interfaces between software and hardware parts based on SysML operations. This method is intended to be applied for the development of drivers involved on what is classically called the “hardware abstraction layer” or the “basic software” which provide high level services for resources management on the top of a bare hardware platform. It is also an enabler for co-design processes since the design of hardware and software can be decoupled. In addition this approach is compatible with virtual prototyping technologies such as SystemC/TLM. An application to a simple a study case is provided for illustration purpose

Making formal verification amenable to real-time UML practitioners

TTool, a real-time UML toolkit, offers user-friendly interfaces to formal verification techniques such as reachability analysis, observer-based analysis and automatic generation of traceability matrices. Those techniques are surveyed in the paper

Knowledge Representation in Engineering 4.0

This dissertation was developed in the context of the BMBF and EU/ECSEL funded projects GENIAL! and Arrowhead Tools. In these projects the chair examines methods of specifications and cooperations in the automotive value chain from OEM-Tier1-Tier2. Goal of the projects is to improve communication and collaborative planning, especially in early development stages. Besides SysML, the use of agreed vocabularies and on- tologies for modeling requirements, overall context, variants, and many other items, is targeted. This thesis proposes a web database, where data from the collaborative requirements elicitation is combined with an ontology-based approach that uses reasoning capabilities. For this purpose, state-of-the-art ontologies have been investigated and integrated that entail domains like hardware/software, roadmapping, IoT, context, innovation and oth- ers. New ontologies have been designed like a HW / SW allocation ontology and a domain-specific "eFuse ontology" as well as some prototypes. The result is a modular ontology suite and the GENIAL! Basic Ontology that allows us to model automotive and microelectronic functions, components, properties and dependencies based on the ISO26262 standard among these elements. Furthermore, context knowledge that influences design decisions such as future trends in legislation, society, environment, etc. is included. These knowledge bases are integrated in a novel tool that allows for collabo- rative innovation planning and requirements communication along the automotive value chain. To start off the work of the project, an architecture and prototype tool was developed. Designing ontologies and knowing how to use them proved to be a non-trivial task, requiring a lot of context and background knowledge. Some of this background knowledge has been selected for presentation and was utilized either in designing models or for later immersion. Examples are basic foundations like design guidelines for ontologies, ontology categories and a continuum of expressiveness of languages and advanced content like multi-level theory, foundational ontologies and reasoning. Finally, at the end, we demonstrate the overall framework, and show the ontology with reasoning, database and APPEL/SysMD (AGILA ProPErty and Dependency Descrip- tion Language / System MarkDown) and constraints of the hardware / software knowledge base. There, by example, we explore and solve roadmap constraints that are coupled with a car model through a constraint solver.Diese Dissertation wurde im Kontext des von BMBF und EU / ECSEL gefördertem Projektes GENIAL! und Arrowhead Tools entwickelt. In diesen Projekten untersucht der Lehrstuhl Methoden zur Spezifikationen und Kooperation in der Automotive Wertschöp- fungskette, von OEM zu Tier1 und Tier2. Ziel der Arbeit ist es die Kommunikation und gemeinsame Planung, speziell in den frühen Entwicklungsphasen zu verbessern. Neben SysML ist die Benutzung von vereinbarten Vokabularen und Ontologien in der Modellierung von Requirements, des Gesamtkontextes, Varianten und vielen anderen Elementen angezielt. Ontologien sind dabei eine Möglichkeit, um das Vermeiden von Missverständnissen und Fehlplanungen zu unterstützen. Dieser Ansatz schlägt eine Web- datenbank vor, wobei Ontologien das Teilen von Wissen und das logische Schlussfolgern von implizitem Wissen und Regeln unterstützen. Diese Arbeit beschreibt Ontologien für die Domäne des Engineering 4.0, oder spezifischer, für die Domäne, die für das deutsche Projekt GENIAL! benötigt wurde. Dies betrifft Domänen, wie Hardware und Software, Roadmapping, Kontext, Innovation, IoT und andere. Neue Ontologien wurden entworfen, wie beispielsweise die Hardware-Software Allokations-Ontologie und eine domänen-spezifische "eFuse Ontologie". Das Ergebnis war eine modulare Ontologie-Bibliothek mit der GENIAL! Basic Ontology, die es erlaubt, automotive und mikroelektronische Komponenten, Funktionen, Eigenschaften und deren Abhängigkeiten basierend auf dem ISO26262 Standard zu entwerfen. Des weiteren ist Kontextwissen, welches Entwurfsentscheidungen beinflusst, inkludiert. Diese Wissensbasen sind in einem neuartigen Tool integriert, dass es ermöglicht, Roadmapwissen und Anforderungen durch die Automobil- Wertschöpfungskette hinweg auszutauschen. On tologien zu entwerfen und zu wissen, wie man diese benutzt, war dabei keine triviale Aufgabe und benötigte viel Hintergrund- und Kontextwissen. Ausgewählte Grundlagen hierfür sind Richtlinien, wie man Ontologien entwirft, Ontologiekategorien, sowie das Spektrum an Sprachen und Formen von Wissensrepresentationen. Des weiteren sind fort- geschrittene Methoden erläutert, z.B wie man mit Ontologien Schlußfolgerungen trifft. Am Schluss wird das Overall Framework demonstriert, und die Ontologie mit Reason- ing, Datenbank und APPEL/SysMD (AGILA ProPErty and Dependency Description Language / System MarkDown) und Constraints der Hardware / Software Wissensbasis gezeigt. Dabei werden exemplarisch Roadmap Constraints mit dem Automodell verbunden und durch den Constraint Solver gelöst und exploriert

Bridging MoCs in SystemC specifications of heterogeneous systems

In order to get an efficient specification and simulation of a heterogeneous system, the choice of an appropriate model of computation (MoC) for each system part is essential. The choice depends on the design domain (e.g., analogue or digital), and the suitable abstraction level used to specify and analyse the aspects considered to be important in each system part. In practice, MoC choice is implicitly made by selecting a suitable language and a simulation tool for each system part. This approach requires the connection of different languages and simulation tools when the specification and simulation of the system are considered as a whole. SystemC is able to support a more unified specification methodology and simulation environment for heterogeneous system, since it is extensible by libraries that support additional MoCs. A major requisite of these libraries is to provide means to connect system parts which are specified using different MoCs. However, these connection means usually do not provide enough flexibility to select and tune the right conversion semantic in amixed-level specification, simulation, and refinement process. In this article, converter channels, a flexible approach for MoC connection within a SystemC environment consisting of three extensions, namely, SystemC-AMS, HetSC, and OSSS+R, are presented.This work is supported by the FP6-2005-IST-5 European project

Complete Model-Based Testing Applied to the Railway Domain

Testing is the most important verification technique to assert the correctness of an embedded system. Model-based testing (MBT) is a popular approach that generates test cases from models automatically. For the verification of safety-critical systems, complete MBT strategies are most promising. Complete testing strategies can guarantee that all errors of a certain kind are revealed by the generated test suite, given that the system-under-test fulfils several hypotheses. This work presents a complete testing strategy which is based on equivalence class abstraction. Using this approach, reactive systems, with a potentially infinite input domain but finitely many internal states, can be abstracted to finite-state machines. This allows for the generation of finite test suites providing completeness. However, for a system-under-test, it is hard to prove the validity of the hypotheses which justify the completeness of the applied testing strategy. Therefore, we experimentally evaluate the fault-detection capabilities of our equivalence class testing strategy in this work. We use a novel mutation-analysis strategy which introduces artificial errors to a SystemC model to mimic typical HW/SW integration errors. We provide experimental results that show the adequacy of our approach considering case studies from the railway domain (i.e., a speed-monitoring function and an interlocking-system controller) and from the automotive domain (i.e., an airbag controller). Furthermore, we present extensions to the equivalence class testing strategy. We show that a combination with randomisation and boundary-value selection is able to significantly increase the probability to detect HW/SW integration errors

The AADL Constraint Annex

The SAE Architecture Analysis and Design Language -- AADL has been defined with a strong focus on the careful modeling of critical real-time embedded systems. Around this formalism, several analysis tools have been defined, e.g. scheduling, safety, security or performance. The SAE AS2-C wishes to complement the AADL with a versatile language to support project-specific analysis. The Model Constraints Sublanguage Annex (or in short the Constraints Annex) provides a standard AADL sublanguage extension with three major objectives: •to allow specification of project specific AADL language subsets and enforce consistent use of the language subset over all classifiers in a package and all packages in a project •to allow specification of project specific Structural Assertions on AADL instance models of component implementations and specification of Structural Assertions on classifier types (component types, feature group types and their extensions) •to allow the specification of Behavior Assertions for feature groups, component types and component implementations, grouped as Assumptions and Guarantees. Assumptions group together Behavior Assertions describing expected behavior of the environment in which a component will operate. Guarantees group together Behavior Assertions which must be honored by all instances of the component, assuming that it is deployed into an environment that honors the Assumptions Behavior Assertions. In this presentation, we will provide an overview of this language, and report on ongoing implementation efforts to date for this language