Online Physical Model Identification for Database-driven Safe Fight Envelope Prediction of Damaged Aircraft

Abstract

This paper presents a novel approach for online identification of the physical condition of damaged aircraft by monitoring and analysing the change of dynamic characteristics of each damage case. As a crucial building block of the database-driven safe flight envelope prediction system, this approach is intended to link the online identification to the offline generated database by finding out the specific key for onboard information retrieval of safe flight envelopes. Simulation results have successfully demonstrated the feasibility of the proposed concept and architecture.

Effects of Structural Failure on the Safe Flight Envelope of Aircraft

“…One important thing to note here is that a successful implementation of the database approach requires an online detection and isolation of faults and damages. This is part of the ongoing research [15][16][17].…”

“…To circumvent the "curse of dimensionality" associated with the nonlinear reachability analysis, a database approach toward flight envelope prediction and protection was first introduced by Tang et al [14], however, the study conducted in this research was only limited to actuator failure scenarios and did not include actual control inputs, rather a "virtual input" in the form of angle of attack for the reachability analysis. The same concept has been recently reintroduced [15][16][17] and extends the implementation of the database approach to structural damages. The basic principle of the database approach is that instead of trying to solve the HJB/HJI equations in real time, a database of safe flight envelopes corresponding to the most often occurring failures is created offline.…”

Aircraft Damage Identification and Classification for Database-Driven Online Flight-Envelope Prediction

“…The effect of the structural damage is mainly a combination of aerodynamic changes and mass (and inertia) shifts [26]. However, mass properties, although coupled with forces and moments, seem not to have a substantial effect on flight characteristics relative to the aerodynamic and control effects, which is according to recent windtunnel experiments in which a large asymmetric mass change (physical separation of an engine) was modeled [15].…”

Database Building and Interpolation for a Safe Flight Envelope Prediction System

“…To circumvent the challenges of updating global model of the impaired aircraft and the high computational load of determing the envelope, a fast database-driven method is proposed in our research, which is reffered to as the "Database-driven safE Flight ENvelope preDiction system (DEFEND)." [20].…”