Guaranteed margins and performance for an adaptive flight control system and application on the X-15 research airplane

The design tools developed for use with linear controllers such as gain and phase margins do not apply to nonlinear control architectures such as adaptive control. For decades, flight control engineers have used these tools extensively to measure the robustness of their linear control systems and make guarantees on the performance of the closed-loop system in the presence of uncertainties. Stringent demands on performance for safety-critical flight systems, as in the case of hypersonic vehicles, make advanced control methods such as adaptive control increasingly attractive. The major obstacle in the widespread application of adaptive control to such applications is the lack of guarantees on performance and robustness. This thesis presents robustness margins, adaptive control analogs to the linear control notions of gain and phase margins, which can be used to make those guarantees. This paves the way for a systematic Verification and Validation (V&V) approach for adaptive controllers. The operation of an adaptive controller can be broken down into two distinct phases: the adaptation mode, in which the adaptive parameters are varying, and the steady-state mode, in which the adaptive parameters have converged to their steady-state values.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Mechanical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Dydek, Zachary Thompson

Advisor dc:contributor.advisor

• Anuradha M. Annaswamy.

• Mechanical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/39868

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/39868