Content area
Full text
Received: 27March 2017/ Accepted 30 April 2017/Published: June 2017
Copyright©2017. Published by INCAS. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
Abstract: Setting the appropriate controllers for aircraft stability and control augmentation systems are complicated and time consuming tasks. As in the Linear Quadratic Regulator method gains are found by selecting the appropriate weights or as in the Proportional Integrator Derivative control by tuning gains. A trial and error process is usually employed for the determination of weighting matrices, which is normally a time consuming procedure. Flight Control Law were optimized and designed by combining the Deferential Evolution algorithm, the Linear Quadratic Regulator method, and the Proportional Integral controller. The optimal controllers were used to reach satisfactory aircraft's dynamic and safe flight operations with respect to the augmentation systems' handling qualities, and design requirements for different flight conditions. Furthermore the design and the clearance of the controllers over the flight envelope were automated using a Graphical User Interface, which offers to the designer, the flexibility to change the design requirements. In the aim of reducing time, and costs of the Flight Control Law design, one fitness function has been used for both optimizations, and using design requirements as constraints. Consequently the Flight Control Law design process complexity was reduced by using the meta-heuristic algorithm.
Key Words: Flight Control; Linear Quadratic Regulator; Optimal Control; Heuristic Algorithm; Differential Evolution; Control Augmentation System; Stability Augmentation System; Proportional Integrator Derivative Tuning.
(ProQuest: ... denotes formulae omitted.)
1. INTRODUCTION
The certification authorities need to ensure that the Flight Control System (FCS) operates properly through the specified flight envelope, when the safety of the new generations of aircrafts, which are fully Flight By Wire (FBW) relay importantly on its FCS. The Flight Control Law (FCL) from design to clearance process is a time consuming process, and it costs, especially for civil aircrafts that need to achieve higher safety. This process aims to prove that the aircraft's robustness and flying requirements are satisfied.
The use of the aircraft flying qualities as requirements criteria in the flight control design is rarely, if ever carried out in the practice [1]. Usually the flight control design is achieved and implemented as a part of avionics system, when the flying qualities...