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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.

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.