Computation of controllability regions for unstable aircraft dynamics.

Date
2004-01-01
Authors
Goman, M. (Mikhail G.)
Demenkov, M. N. (Max)
Journal Title
Journal ISSN
ISSN
0731-5090
1533-3884
Volume Title
Publisher
American Institute Aeronautics and Astronautics
Peer reviewed
Abstract
An active control approach to air vehicle design can significantly expand the flight envelope and improve vehicle performance characteristics. In some cases it can be attained by implementing the aerodynamically unstable configuration or expanding operation at flight regimes with dynamic instability, which are then purposely stabilized by the flight control system. An important issue in stabilization of unstable dynamics is connected with the size of the controllability region, which is the set of all states of the aircraft dynamics that can be stabilized by some realizable control action. This region is bounded because of nonlinear actuator constraints, and its size can be considered as a measure for allowable level of external disturbances. In this paper an algorithm based on convex optimization technique is proposed for computation of the controllability region of an unstable linear system under amplitude and rate control constraints. Examples of the controllability region analysis for an aeroservoelastic airfoil system and unstable aircraft dynamics are presented to illustrate the capabilities of the proposed algorithm.
Description
This output describes an approach based on geometrical and optimisation principles that resulted in efficient software tools for computation of null controllability region of unstable dynamical systems. The software toolset, “Stabcalcs” has been created and tested on several flight dynamics applications and delivered to DERA/QinetiQ Ltd. within Computational Framework for flight clearance applications (in 2002-2003, DERA/QinetiQ Ltd Technical Manager Yoge Patel, yoge@bbsr.co.uk). The research was sponsored by QinetiQ Ltd.
Keywords
RAE 2008, UoA 28 Mechanical, Aeronautical and Manufacturing Engineering
Citation
Goman, M.G. and Demenkov, M.N. (2004) Computation of controllability regions for unstable aircraft dynamics. Journal of Guidance, Control, and Dynamics, 27 (4), pp. 647-656.
Research Institute