Aircraft braking dynamics and brake system modeling for fault detection and isolation

Abstract

Due to the increasing complexity of aeronautical systems, it became more and more important to detect possible failures, avoiding costs with maintenance and time out of operation. Modeling techniques and computational softwares made possible to analyze systems behaviour under normal and failure conditions, helping to prevent these problems. In this work, an aircraft anti-skid brake system is considered as a study case. Therefore, the aircraft brake dynamics and the brake system are modeled using Simulink. In the brake model, some common faults are introduced in order to observe its impacts on the braking performance. A model based fault detection and isolation (FDI) method using analytical redundancy relations (ARRs) is proposed. ARRs are equations relating the system constraints. The numerical evaluation of these equations generates residuals indicating the system deviation from its normal operation. The coupling of the Simulink behavior model with the ARRs is presented, permitting the residuals analyses for each failure mode.