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In the aerospace industry, as the modern avionics systems became more and more complex, the Integrated Modular Avionics (IMA) architecture has been proposed as a replacement of the federated architecture, in order to offer better solutions on SWaP constraints (Size, Weigh and Power). However, the development process of IMA avionics systems is much more difficult. This paper aims to propose to the aerospace industry a set of time-effective and cost-effective solutions for the integration and functional validation of IMA systems. Based on MBE methodology, which is considered as an interesting solution for the IMA systems development [8], this paper proposes a design flow, that integrates three steps of refinement, for the configuration and the validation of IMA platforms. In the first step of the design flow, the modeling language AADL is used to describe the IMA architecture.

Design assurance guidance such as DO-254, and commercial off the shelf (COTS) increasing popularity in high critical mission have pushed the validation and verification methodologies to improve by integrating fault tolerance analysis in reliability assessment. A novel methodology for analysing the sensitivity of digital designs to single event upsets (SEU) is proposed. We first characterize basic combinational circuit models using fault injection via mutation technique at low level of abstraction. Error analysis is performed at primary outputs to identify patterns that are collected in a faulty behaviour library. This library is then used at a high level of abstraction to execute a sensitivity analysis on a digital design model. A reliability report is then generated showing the soft error rate (SER) and the benign errors count. We proved our methodology by analysing the radiation sensitivity of a discrete wavelet transform architecture using two different sets of data.

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.

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.

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.

This paper presents a fault tolerant flight control design for the longitudinal linear model of the Boeing 737-100. The EMMAE (Extended Multiple Model Adaptive estimation) method is used to design the FDD process (Fault Detection and Diagnosis). Based essentially on a set of EKFs (Extended Kalman Filters), this method makes it possible to simulate several types of faults including stuck and oscillation. To develop the RFC (Reconfigurable Flight Control) law, SMC (Sliding Mode Control) method [11] is used. To rigorously investigate the performance of the overall system with respect of interactions between the two subsystems, The MRAC (Model Reference Adaptive Control) method [3] is used for comparison. Several simulation results using Matlab and Simulink show the desired system performance with fault compensation.