Aircraft Loss-Of-Control Recovery Using Feedback Linearization and High Order Sliding Mode Control

Abstract

The complexity of modern commercial, military aircraft and space vehicles requires an advanced level of automation that would prevent aircraft and space vehicles from losing controllability and maneuverability due to system failures, exogenous disturbances, upset near critical points and operation near the boundaries of the ight envelope. The advanced level of automation would assists pilots during the recovering ight regime following post Loss - Of - Control (LOC). Here, recovery is dened as the ability to regulate and or track key variables to an acceptable performance during o - nominal ight regimes that are qualied as LOC. Few research reports directly address the connection of LOC with in ight bifurcation phenomenon which are ordinarily associated with upset ight vehicle. Such bifurcation points are not usually associated to a particular system failure of components but once the ight vehicle maneuvers near those in ight points, it loses its ability to be regulated or tracked particular trajectory due to the occurrence of structurally unstable zero dynamics. Throughout this analysis, an investigation of bifurcation points is carried out and a recovery strategy is designed using Feedback Linearization (FBL) and High Order Sliding Mode Control techniques where Dynamic Extension is used to mitigate singularity of the decoupling matrix. An attempt to address the control bounds is also investigated because ight recovery may require an extension of the normal bounds of the ight envelope. The resulting controller would assist pilots during post LOC to steer the