Print Email Facebook Twitter An optimal control framework for estimating autopilot safety margins Title An optimal control framework for estimating autopilot safety margins Author Govindarjan, N. De Visser, C.C. Van Kampen, E. Krishnakumar, K. Barlow, J. Stepanyan, V. Faculty Aerospace Engineering Department Control & Operations Date 2014-06-27 Abstract This paper presents an optimal control framework to determine a collection of open-loop command signals that mathematically guarantees operation of an aircraft within certain prescribed state constraints. The framework is specifically applied to estimate margins for the reference command inputs of aircraft autopilot systems, so that safe operation within a given flight envelope can be assured under appropriate control action. Flight envelope excursions are generally considered as precursors to Loss-Of-Control incidents, and hence, these margins contain safety critical information that can help improve the situational awareness on-board the aircraft. In off-nominal conditions, the computed safety margins provide indications of a degraded aircraft with reduced flying and handling qualities. These indications appear in the form of increasingly more strict limits on the autopilot reference command input. The entire framework is illustrated on an example problem involving a pitch dynamics model with state constraints on the pitch attitude. Simulations are conducted wherein margins are computed for the reference pitch command of the pitch hold system, while the aircraft enters an off-nominal condition with severely degraded system dynamics and reduced elevator effectiveness. Subject optimal controlmultivariate splinesaircraft safetyloss of control To reference this document use: http://resolver.tudelft.nl/uuid:e02db37b-5e7c-4139-8576-cd210f3c8dc3 Publisher AIAA ISSN 0731-5090 Source Journal of Guidance, Control, and Dynamics, 2014; Authors version Other version http://arc.aiaa.org/doi/full/10.2514/1.G000271 Part of collection Institutional Repository Document type journal article Rights © 2014 American Institute of Aeronautics and Astronautics Files PDF Govindarajan2014_HJBsafet ... est_vF.pdf 219.68 KB Close viewer /islandora/object/uuid:e02db37b-5e7c-4139-8576-cd210f3c8dc3/datastream/OBJ/view