Georgia Tech Research Corporation

The Boeing Company

University of Illinois

University of Connecticut

Naira Hovakimyan

Anthony J Calise

Eugene Lavretsky

Bong-Jun Yang

Moshe Idan

Chengyu Cao

Enric Xargay

C Anthony Calise

Systems and methods of adaptive control for uncertain nonlinear multi-input multi-output systems in the presence of significant unmatched uncertainty with assured performance are provided. The need for gain-scheduling is eliminated through the use of bandwidth-limited (low-pass) filtering in the control channel, which appropriately attenuates the high frequencies typically appearing in fast adaptation situations and preserves the robustness margins in the presence of fast adaptation.

Adaptive control for uncertain nonlinear multi-input multi-output systems

An adaptive control system is provided that scales both gain and commands to avoid input saturation. The input saturation occurs when a commanded input uexceeds an achievable command limit of u. To avoid input saturation, the commanded input uis modified according to a factor &#x3bc;.

Adaptive control in the presence of input constraints

The invention comprises apparatuses and methods for providing the capability to stabilize and control a non-minimum phase, nonlinear plant with unmodeled dynamics and/or parametric uncertainty through the use of adaptive output feedback. A disclosed apparatus can comprise a reference model unit for generating a reference model output signal yThe apparatus can comprise a combining unit that combines and differences a plant output signal y of a non-minimum phase plant for which not all of the states can be sensed, and a plant output signal y, to generate an output error signal {tilde over (y)}. The apparatus can further comprise an adaptive control unit for generating an adaptive control signal uused to control the plant.

Adaptive output feedback apparatuses and methods capable of controlling a non-minimum phase system

An adaptive control method is provided that scales both gain and commands to avoid input saturation. The input saturation occurs when a commanded input uexceeds an achievable command limit of u. To avoid input saturation, the commanded input uis modified according to a factor &#x3bc;.

An adaptive control system (ACS) uses direct output feedback to control a plant. The ACS uses direct adaptive output feedback control developed for highly uncertain nonlinear systems, that does not rely on state estimation. The approach is also applicable to systems of unknown, but bounded dimension, whose output has known, but otherwise arbitrary relative degree. This includes systems with both parameter uncertainty and unmodeled dynamics. The result is achieved by extending the universal function approximation property of linearly parameterized neural networks to model unknown system dynamics from input/output data. The network weight adaptation rule is derived from Lyapunov stability analysis, and guarantees that the adapted weight errors and the tracking error are bounded.

Adaptive control system having direct output feedback and related apparatuses and methods

The invention comprises apparatuses and methods for providing the capability to stabilize and control a non-minimum phase, nonlinear plant with unmodeled dynamics and/or parametric uncertainty through the use of adaptive output feedback. A disclosed apparatus can comprise a reference model unit for generating a reference model output signal y. The apparatus can comprise a combining unit that combines and differences a plant output signal y of a non-minimum phase plant for which not all of the states can be sensed, and a plant output signal y, to generate an output error signal {tilde over (y)}. The apparatus can further comprise an adaptive control unit for generating an adaptive control signal uused to control the plant.

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Smyrna, GA, United States of America

Naira Hovakimyan