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The increased use of FPGAs over the past decade has induced an increased concern about radiation effects, in particular the effects of single event upsets (SEU) in SRAM-based FPGAs. Technology scaling and density increase have caused FPGAs to be more vulnerable to SEU. Therefore, external radiations present an issue not only for space based systems; but also for critical terrestrial applications operating in harsh environment, such as commercial avionics. In order to build robust fault tolerant systems, SEU effects have to be analyzed and modeled so that the designer understands and considers the system's possible faulty behaviors. In this paper, we present a complete automated methodology, based on the use of SEU controller provided by Xilinx, to efficiently emulate SEUs on an FPGA design and extract possible fault models based on radiation effects. The proposed method is applied on a reconfigurable flight control system based on a reference adaptive control model.

Avionic Full-Duplex Switched Ethernet (AFDX) is one of the most promising solutions developed in recent years for implementing high-bandwidth Avionic Data Networks (ADNs) that can support the increasingly high information flow required by modern avionic systems. Although AFDX commercial products are available, developing custom implementations using generic software and hardware, without depending on third-party products, allows identifying practical challenges and constraints, prototyping and characterizing new architectures, testing new algorithms, as well as performing validation and verification in the early stage of development. In this paper, we show how an AFDX switch fabric hardware core can be designed and implemented on an FPGA to facilitate the prototyping of a generic ADN in an early development stage.

With the next generation of avionics systems, more sensors and actuators will be required for an ever increasing number of functions. In this paper, we propose a system architecture based on several enhancements to the IEEE 1451 standard, granting it a wider application range, improved resource efficiency and a generic and reusable character. This architecture facilitates the integration of next generation smart sensors with a wide range of avionics data communication networks and allows the specification of generic features to be respected. In order to meet the requirements of avionics applications, this architecture that provides a design framework offers customization of features such as bandwidth, reliability, resources utilization and compatibility with different types of transducers, especially smart sensors. The resulting resource utilization and reliability are analyzed for several configurations that provide a basis for comparison.

The Integrated Modular Avionics (IMA) architecture has been a crucial concern for the aerospace industry in developing more complex systems, while seeking to reduce space, weight and power (SWaP), as well as development, certification and production time. From a software perspective, that objective pushes developers to migrate toward safety critical space and time partitioning environment. However, mainstream commercial real-time operating systems (RTOS) offering such partitioning can be restrictive in early development due to very high licensing costs. That situation is even more striking when considering that low-cost alternatives could instead be used for system modeling and early simulation before acquisition of a target platform. This paper reviews existing low-cost and open-source development environments to propose a novel design flow. The proposed methodology starts with model-based analysis in the AADL modeling language.

The main goal of this flight control system is to achieve good performance with acceptable flying quality within the specified flight envelope while ensuring robustness for model variations, such as mass variation due to fuel burn. The Cessna Citation X aircraft linear model is presented for different flight conditions to cover the aircraft's flight envelope, on which a robust controller is designed using the H-infinity method optimized by two heuristic algorithms. The optimal controller was used to achieve satisfactory dynamic characteristics for the longitudinal and lateral stability control augmentation systems with respect to this aircraft's flying quality requirements. The weighting functions of the H-infinity method were optimised by using both genetic and differential evolution algorithms. The evolutionary algorithms gave very good results.

During aircraft development, mathematical models are elaborated from our knowledge of fundamental physical laws. Those models are used to gain knowledge in order to make the best decisions at all development stages. Depending on the application, different models can be used to describe, in one way or another, the aircraft behavior. The goal of this paper is to develop a high-fidelity aircraft simulation model that is exceptionally capable, flexible and responsive to the needs of the researchers. The proposed model includes nonlinear aerodynamic coefficients, a generic engine model and a complete autopilot with auto-landing. The simulation model has been designed to help researchers develop and validate new algorithms for trajectory optimization, control design, stability analysis and parameter estimation. To make it easy to use, the simulation model also includes algorithms for stability and control analysis.

The amount of functionalities in modern aircrafts is increasing to satisfy performance, safety and economic benefits. Therefore, the communication needs of avionic systems are growing. Furthermore, the portability and reusability of applications are current challenges of the aerospace industry. The use of the Data Distribution Service (DDS) middleware technology would reduce the complexity of communications and ease the portability and reusability of applications with its standardised interface. Few previous works used a DDS middleware within the aerospace industry and those didn't take into account the impact of this technology on the applications performances. Therefore, this paper presents an impact evaluation of using a DDS middleware on the performances of avionic applications.