Database-driven Safe Flight Envelope Protection for Impaired Aircraft

Abstract

In this paper, an online flight envelope protection system is developed and implemented on impaired aircraft with structural damage. The whole protection system is designed to be a closed-loop of several subsystems , including system identification, damage classification, flight-envelope prediction and fault-tolerant control. Based on the information given by damage classification, the flight envelopes are explicitly retrieved and processed online from the database and fed into the fault-tolerant controller, which makes the protection system adaptive to a wide range of abnormal conditions. Simulation results show that with envelope protection, loss-ofcontrol accidents are more likely to be prevented, since both the controller and pilots are aware of the shrunken flight envelopes after damage and excessive commands are restricted. In this way, the fault-tolerance of the impaired aircraft can be effectively enhanced.

Flight safety warning of iced aircraft based on reachability analysis and fuzzy inference

“…A level set algorithm can be employed to solve the viscosity solution f(x, t) of equation (10). In this paper, Mitchell's level set toolbox 17 was employed.…”

“…After setting the boundary conditions and finding the optimal solutions T à and d à e , the level set toolbox can be employed to solve the Hamilton-Jacobi equation (10), and the viscosity solution f(x, t) can be obtained. In this paper, V min = 90ft=s, V max = 120ft=s, a min = 0 deg, a max = 15 deg, u min = À 15 deg, u max = 30 deg, q min = À 40deg=s, q max = 40deg=s, T min = 0 lbf,…”

“…ICEPro uses a of a-priori information and real-time aerodynamic estimations to provide safe limits of the flight envelope during in-flight icing encounters. In Zhang et al, 10 a database-driven safe flight envelope protection method is proposed for abnormal cases like structural damage and icing occur. Based on the information given by damage classification, the flight envelopes are explicitly retrieved and processed online from the database.…”