Nonlinear Control of Mechanical Systems in the Presence of Magnitude and Rate Saturations

Richard M. Murray
California Institute of Technology

Office of Naval Research

This program ran from 1996-1999 under support by the Office of Naval Research.  This information was collected by Richard M. Murray; this page is no longer actively maintained, but serves as an archive for work performed under this grant.

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This project is aimed at developing systematic techniques for control of mechanical systems in the presence of magnitude and rate saturations, with particular emphasis on problems arising in the context of high performance aircraft. Magnitude and rate saturations are a major source of nonlinearities in all flight control systems and are a fundamental mechanism of instability in both automated and piloted flight. Recent theoretical developments in nonlinear control theory as well as increasing computational power in offline and online computation are enabling the use of more powerful techniques for control of these systems.

The proposed research builds on an established base of work in nonlinear control of mechanical systems and stabilization of strongly nonlinear systems to explore new approaches to this problem. In addition to developing theoretical tools for analysis of flight control systems with saturations, experimental validation of the techniques will be carried out using a flight control experiment at Caltech that exhibits many of the essential features of aircraft systems while remaining simple enough to allow meaningful testing of fundamental feedback mechanisms. Industrial participation with Honeywell Technology Center and McDonnell Douglas Corporation provides a direct path for successful techniques into industry and provides feedback mechanisms to insure the applicability of the proposed work.

Students, Postdocs, and Visitors

The following individuals received partial support from this program:


Differentially Flat Systems with Inequality Constraints: An Approach to Real-Time Feasible Trajectory Generation
Nadim Faiz, Sunil Agrawal and Richard Murray
To appear, J. Guidance, Navigation and Control, 2000

Geometric Approaches to Control in the Presence of Magnitude and Rate Saturations
Richard M. Murray
In The Astrom Symposium on Control, pp. 43-72, 1999

Feasible Trajectories of Linear Dynamic Systems with Inequality Constraints Using Higher­Order Representations
Sunil K. Agrawal, Nadeem Faiz, Richard M. Murray
1999 IFAC World Congress

Nonlinear Rescaling of Control Laws with Application to Stabilization in the Presence of Magnitude Saturation
Pascal Morin, Richard M. Murray, Laurent Praly
1998 IFAC Symposium on Nonlinear Control Systems Design (NOLCOS)

Stabilization of a Pitch Axis Flight Control Experiment with Input Rate Saturation
Trygve Lauvdal and Richard M. Murray
1997 AIAA Guidance, Navigation and Control Conference

Stabilization of Integrator Chains in the Presence of Magnitude and Rate Saturations: A Gain Scheduling Approach
Trygve Lauvdal, Richard M. Murray, Thor I. Fossen
1997 Conference on Decision and Control

Uniting local and global controllers for the Caltech ducted fan
Andrew R. Teel, Oliver Kaiser, Richard M. Murray
1997 American Control Conference

Additional information

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Last modified: 12/27/00