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This paper presents the SCADE System™ product line for systems modeling and generation based on the SysML standard and the Eclipse Papyrus open source technology. SCADE System has been developed in the framework of Listerel, a joint laboratory of Esterel Technologies, provider of the SCADE® tools, and CEA LIST, project leader of the Eclipse component, Papyrus. From an architecture point of view, the Esterel SCADE tools are built on top of the SCADE platform which includes both SCADE Suite®, a model-based development environment dedicated to critical software, and SCADE System enabling model-based system engineering. SCADE System includes Papyrus, an open source component (under EPL license), integrated in the modeling platform of Eclipse. Using this integrated modeling platform, both system and software teams share the same environment for system development. Furthermore, other model-based tools can be added to the environment, due to the use of Eclipse.

The design of integrated modular avionics (IMA) for next-generation aircraft is a significant challenge for the industry in terms of complexity, time-to-market, certification and design effort. Because of those constraints, traditional hand-coding may no longer be a cost-effective option, especially for DO-178C Design Assurance Level (DAL) A Safety-critical applications. While the use of Commercial Off-The-Shelf (COTS) HMI-modeling tools could be a more efficient option, its introduction in an existing environment may result in high risk and effort. This paper presents the approach for the evaluation of the SCADE Display tool for a primary flight display (PFD) application. In this evaluation, a subset of a previously developed PFD was re-modeled with SCADE Display. The creation of the model served as an evaluation of the usability and the flexibility of the tool. The integration of the generated code on an existing platform was evaluated.

The ARINC 661 standard [1] defines a Cockpit Display System (CDS) interface intended for all types of aircrafts installations. This paper presents an integrated solution based on Commercial Off-The-Shelf (COTS) tools that allows, in the initial stage of an aircraft project, support for the expression of requirements with regards to the CDS definition and the CDS interaction with the User Applications (UAs). It also enables prototyping of the systems architecture from the point of view of functionalities and performance. At a later stage of the project, this same integrated tool suite can be used to produce and certify the final embedded software code within the CDS and to generate the communication code between the CDS and the UAs.

Formal verification is increasingly used for checking and proving the correctness of digital systems. In this paper, we present formal verification as a cost-effective technique for the verification and validation of model-based safety-critical embedded systems. We start by explaining how formal verification can be easily integrated in a model-based development methodology for critical embedded software. In the methodology examined, the development methods are based upon a formal and deterministic language representation and a correct-by-construction automatic code generation. In this methodology, formal verification proves that what you execute conforms to safety requirements, and what you execute is exactly what you embed. We show the impacts and benefits of using formal verification in software development that must be compliant with the IEC 61508 standards, especially for SIL 3 and SIL 4 software development.

This paper presents a method to determine the root cause of an aircraft component failure by means of the aircraft fault messages history. The k-Nearest Neighbors (k-NN) and the Tree-Augmented naive Bayes (TAN) methods were used in order to classify the failure causes as a function of the fault messages (predictors). The contribution of this work is to show how well the fault messages of aircraft systems can classify specific components failure modes. The training set contained the messages history from a fleet and the root causes of a butterfly valve reported by the maintenance stations. A cross-validation was performed in order to check the loss function value and to compare both methods performance. It is possible to see that the use of just fault messages for the valve failure classification provides results that close to 2/3 and could be used for faster troubleshooting procedures.

Embraer began development of an ARINC 661-compliant cockpit display system with Esterel Technologies SCADE Solutions for ARINC 661 Applications. Over the past two years, Embraer has been able to build a fully-functional ARINC 661 demonstrator that includes all components necessary for CDS deployment under the ARINC 661 standard. The ARINC 661 demonstrator includes a fully-compliant ARINC 661 server based originally on Esterel Technologies SCADE 661 Server Creator using an automatic server generator. Embraer had successfully integrated a custom ARINC 661-4, widgets library, with Esterel Technologies widget library, designed with SCADE as the base. Embraer has also developed and integrated User Applications running on a IMA hardware system and communicating with the server using UDP over AFDX within a flight simulator system. This paper discuss the process followed by Embraer for development of the ARINC 661 demonstrator.

Model Based System Engineering is considered today as the approach that can meet the continually growing complexity of avionics, a challenge that is compounded by constant market pressure (cost, time to market, need for product variants…) For each activity in the product life cycle, tools and technologies supporting an MBSE approach already exist, such as embedded code generation, formal safety analysis, electrical harness design; however, one of the greatest challenges consists in integrating these diverse system development tools into a global framework that ensures the consistency of perspectives and a seamless workflow across processes. Citrus is being developed as an open environment that targets the main activities of systems and software engineering: modeling and validating functions, allocating functional and non-functional requirements to systems, developing the physical architecture, interface design, allocating system requirements to software and hardware items.

1 The current pressure across the entire aerospace industry to reduce operating costs and increase efficiency has arguably never been greater. Thus the need to improve parameters such as availability and reliability, and increase the tools and services associated with more efficient aircraft operations and sustainment is now paramount. Moreover, these improvements are seen by many as important factors that define the differentiation and competitiveness of not only current but also future aircraft fleets. The paper will focus on some of the opportunities for OEMs that arise from implementing Integrated Vehicle Health Management (IVHM) systems on their platforms and the challenges associated with evaluating the costs and benefits of their implementation and operation.

The cost-benefit analysis is one of the key decision aspects regarding the investment on IVHM systems especially for aerospace applications where the evaluation of the impacts of such systems on costs, safety and weight are critical for the vehicle operation during its lifecycle. This paper presents the application of linear programming to select and to quantify how many components an IVHM system should consider in order to maximize the total value that it delivers. This approach advantage is that it uses an exact algorithm, that guarantees the optimal solution given the inputs provided by the user. The formulation shows how the technical value of an IVHM solution can be evaluated taking into account key aspects for aerospace platforms such as weight, reliability and bus capacity restrictions through a linear integer programming model solved using the branch-and-bound method.

This paper introduces a model-based systems and embedded software engineering, workflow for the design of control systems. The interdisciplinary approach that is presented relies on an integrated set of tools that addresses the needs of various engineering groups, including system architecture, design, and validation. For each of these groups, a set of best practices has been established and targeted tools are proposed and integrated in a unique platform, thus allowing efficient communication between the various groups. In the initial stages of system design, including functional and architectural design, a SysML-based approach is proposed. This solution is the basis to develop systems that have to obey both functional and certification standards such as ARINC 653 (IMA) and ARP 4754A. Detailed system design typically requires modeling and simulation of each individual physical component of the system by various engineering groups (mechanical, electrical, etc.).