Adaptive Control for a Biological Process under Input Saturation and Unknown Control Gain via Dead Zone Lyapunov Functions

In this work, substrate control of a biological process with unknown varying control gain, input saturation, and uncertain reaction rate is addressed. A novel adaptive controller is proposed, which tackles the combined effect of input saturation and unknown varying control gain with unknown upper an...

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Main Authors: Alejandro Rincón, Fredy E. Hoyos, John E. Candelo-Becerra
Format: Article
Language:English
Published: MDPI AG 2020-12-01
Series:Applied Sciences
Subjects:
Online Access:https://www.mdpi.com/2076-3417/11/1/251
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author Alejandro Rincón
Fredy E. Hoyos
John E. Candelo-Becerra
author_facet Alejandro Rincón
Fredy E. Hoyos
John E. Candelo-Becerra
author_sort Alejandro Rincón
collection DOAJ
description In this work, substrate control of a biological process with unknown varying control gain, input saturation, and uncertain reaction rate is addressed. A novel adaptive controller is proposed, which tackles the combined effect of input saturation and unknown varying control gain with unknown upper and lower bounds. The design is based on dead zone radially unbounded Lyapunov-like functions, with the state backstepping as control framework. The convergence of the modified tracking error and the boundedness of the updated parameters are ensured by means of the Barbalat’s lemma. As the first distinctive feature, a new second-order auxiliary system is proposed that tackles the effect of saturated input and the unknown varying control gain with unknown upper and lower bounds. As the second distinctive feature, the modified tracking error converges to a compact set whose width is user-defined, so that it does not depend on bounds of either external disturbances, model terms, or model coefficients. The convergence region of the current tracking error is determined for the closed loop system subject to the formulated controller and the proposed auxiliary system. Finally, numerical simulation illustrates the performance of the proposed controller.
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spelling doaj.art-f5f4996f0ce9434c887ce7f790a289542023-11-21T02:58:07ZengMDPI AGApplied Sciences2076-34172020-12-0111125110.3390/app11010251Adaptive Control for a Biological Process under Input Saturation and Unknown Control Gain via Dead Zone Lyapunov FunctionsAlejandro Rincón0Fredy E. Hoyos1John E. Candelo-Becerra2Grupo de Investigación en Desarrollos Tecnológicos y Ambientales—GIDTA, Facultad de Ingenieria y Arquitectura, Universidad Católica de Manizales, Carrera 23 No. 60-63, Manizales 170002, ColombiaFacultad de Ciencias, Escuela de Física, Universidad Nacional de Colombia, Sede Medellín, Carrera 65 No. 59A, 110, Medellín 050034, ColombiaDepartamento de Energía Eléctrica y Automática, Facultad de Minas, Universidad Nacional de Colombia, Sede Medellín, Carrera 80 No. 65-223, Robledo, Medellín 050041, ColombiaIn this work, substrate control of a biological process with unknown varying control gain, input saturation, and uncertain reaction rate is addressed. A novel adaptive controller is proposed, which tackles the combined effect of input saturation and unknown varying control gain with unknown upper and lower bounds. The design is based on dead zone radially unbounded Lyapunov-like functions, with the state backstepping as control framework. The convergence of the modified tracking error and the boundedness of the updated parameters are ensured by means of the Barbalat’s lemma. As the first distinctive feature, a new second-order auxiliary system is proposed that tackles the effect of saturated input and the unknown varying control gain with unknown upper and lower bounds. As the second distinctive feature, the modified tracking error converges to a compact set whose width is user-defined, so that it does not depend on bounds of either external disturbances, model terms, or model coefficients. The convergence region of the current tracking error is determined for the closed loop system subject to the formulated controller and the proposed auxiliary system. Finally, numerical simulation illustrates the performance of the proposed controller.https://www.mdpi.com/2076-3417/11/1/251input saturationuncertain nonlinear systemadaptive controlunknown control gainbackstepping controldead zone Lyapunov function
spellingShingle Alejandro Rincón
Fredy E. Hoyos
John E. Candelo-Becerra
Adaptive Control for a Biological Process under Input Saturation and Unknown Control Gain via Dead Zone Lyapunov Functions
Applied Sciences
input saturation
uncertain nonlinear system
adaptive control
unknown control gain
backstepping control
dead zone Lyapunov function
title Adaptive Control for a Biological Process under Input Saturation and Unknown Control Gain via Dead Zone Lyapunov Functions
title_full Adaptive Control for a Biological Process under Input Saturation and Unknown Control Gain via Dead Zone Lyapunov Functions
title_fullStr Adaptive Control for a Biological Process under Input Saturation and Unknown Control Gain via Dead Zone Lyapunov Functions
title_full_unstemmed Adaptive Control for a Biological Process under Input Saturation and Unknown Control Gain via Dead Zone Lyapunov Functions
title_short Adaptive Control for a Biological Process under Input Saturation and Unknown Control Gain via Dead Zone Lyapunov Functions
title_sort adaptive control for a biological process under input saturation and unknown control gain via dead zone lyapunov functions
topic input saturation
uncertain nonlinear system
adaptive control
unknown control gain
backstepping control
dead zone Lyapunov function
url https://www.mdpi.com/2076-3417/11/1/251
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AT johnecandelobecerra adaptivecontrolforabiologicalprocessunderinputsaturationandunknowncontrolgainviadeadzonelyapunovfunctions