Fixed-Time Distributed Time-Varying Optimization for Nonlinear Fractional-Order Multiagent Systems with Unbalanced Digraphs

This paper investigates the problem of fixed-time distributed time-varying optimization of a nonlinear fractional-order multiagent system (FOMAS) over a weight-unbalanced directed graph (digraph), where the heterogeneous unknown nonlinear functions and disturbances are involved. The aim is to cooper...

Full description

Bibliographic Details
Main Authors: Kun Wang, Ping Gong, Zhiyao Ma
Format: Article
Language:English
Published: MDPI AG 2023-11-01
Series:Fractal and Fractional
Subjects:
Online Access:https://www.mdpi.com/2504-3110/7/11/813
_version_ 1797459295131926528
author Kun Wang
Ping Gong
Zhiyao Ma
author_facet Kun Wang
Ping Gong
Zhiyao Ma
author_sort Kun Wang
collection DOAJ
description This paper investigates the problem of fixed-time distributed time-varying optimization of a nonlinear fractional-order multiagent system (FOMAS) over a weight-unbalanced directed graph (digraph), where the heterogeneous unknown nonlinear functions and disturbances are involved. The aim is to cooperatively minimize a convex time-varying global cost function produced by a sum of time-varying local cost functions within a fixed time, where each time-varying local cost function does not have to be convex. Using a three-step design procedure, a fully distributed fixed-time optimization algorithm is constructed to achieve the objective. The first step is to design a fully distributed fixed-time estimator to estimate some centralized optimization terms within a fixed time <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>T</mi><mn>0</mn></msub></semantics></math></inline-formula>. The second step is to develop a novel discontinuous fixed-time sliding mode algorithm with nominal controller to derive all the agents to the sliding-mode surface within a fixed time <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>T</mi><mn>1</mn></msub></semantics></math></inline-formula>, and meanwhile the dynamics of each agent is described by a single-integrator MAS with nominal controller. In the third step, a novel estimator-based fully distributed fixed-time nominal controller for the single-integrator MAS is presented to guarantee all agents reach consensus within a fixed time <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>T</mi><mn>2</mn></msub></semantics></math></inline-formula>, and afterwards minimize the convex time-varying global cost function within a fixed time <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>T</mi><mn>3</mn></msub></semantics></math></inline-formula>. The upper bound of each fixed time <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>T</mi><mi>m</mi></msub><mspace width="3.33333pt"></mspace><mrow><mo>(</mo><mi>m</mi><mo>=</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>,</mo><mn>2</mn><mo>,</mo><mn>3</mn><mo>)</mo></mrow></mrow></semantics></math></inline-formula> is given explicitly, which is independent of the initial states. Finally, a numerical example is provided to validate the results.
first_indexed 2024-03-09T16:49:25Z
format Article
id doaj.art-f4d97a837fdf414087eb0d8fbcc9832b
institution Directory Open Access Journal
issn 2504-3110
language English
last_indexed 2024-03-09T16:49:25Z
publishDate 2023-11-01
publisher MDPI AG
record_format Article
series Fractal and Fractional
spelling doaj.art-f4d97a837fdf414087eb0d8fbcc9832b2023-11-24T14:43:04ZengMDPI AGFractal and Fractional2504-31102023-11-0171181310.3390/fractalfract7110813Fixed-Time Distributed Time-Varying Optimization for Nonlinear Fractional-Order Multiagent Systems with Unbalanced DigraphsKun Wang0Ping Gong1Zhiyao Ma2School of Mathematics and Information Science, Guangzhou University, Guangzhou 510006, ChinaSchool of Mathematics and Statistics, Guangdong University of Foreign Studies, Guangzhou 510006, ChinaCollege of Science, Liaoning University of Technology, Jinzhou 121001, ChinaThis paper investigates the problem of fixed-time distributed time-varying optimization of a nonlinear fractional-order multiagent system (FOMAS) over a weight-unbalanced directed graph (digraph), where the heterogeneous unknown nonlinear functions and disturbances are involved. The aim is to cooperatively minimize a convex time-varying global cost function produced by a sum of time-varying local cost functions within a fixed time, where each time-varying local cost function does not have to be convex. Using a three-step design procedure, a fully distributed fixed-time optimization algorithm is constructed to achieve the objective. The first step is to design a fully distributed fixed-time estimator to estimate some centralized optimization terms within a fixed time <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>T</mi><mn>0</mn></msub></semantics></math></inline-formula>. The second step is to develop a novel discontinuous fixed-time sliding mode algorithm with nominal controller to derive all the agents to the sliding-mode surface within a fixed time <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>T</mi><mn>1</mn></msub></semantics></math></inline-formula>, and meanwhile the dynamics of each agent is described by a single-integrator MAS with nominal controller. In the third step, a novel estimator-based fully distributed fixed-time nominal controller for the single-integrator MAS is presented to guarantee all agents reach consensus within a fixed time <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>T</mi><mn>2</mn></msub></semantics></math></inline-formula>, and afterwards minimize the convex time-varying global cost function within a fixed time <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>T</mi><mn>3</mn></msub></semantics></math></inline-formula>. The upper bound of each fixed time <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>T</mi><mi>m</mi></msub><mspace width="3.33333pt"></mspace><mrow><mo>(</mo><mi>m</mi><mo>=</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>,</mo><mn>2</mn><mo>,</mo><mn>3</mn><mo>)</mo></mrow></mrow></semantics></math></inline-formula> is given explicitly, which is independent of the initial states. Finally, a numerical example is provided to validate the results.https://www.mdpi.com/2504-3110/7/11/813fixed-time distributed optimizationfractional-order multiagent systemsweight-unbalanced digraphtime-varying cost functions
spellingShingle Kun Wang
Ping Gong
Zhiyao Ma
Fixed-Time Distributed Time-Varying Optimization for Nonlinear Fractional-Order Multiagent Systems with Unbalanced Digraphs
Fractal and Fractional
fixed-time distributed optimization
fractional-order multiagent systems
weight-unbalanced digraph
time-varying cost functions
title Fixed-Time Distributed Time-Varying Optimization for Nonlinear Fractional-Order Multiagent Systems with Unbalanced Digraphs
title_full Fixed-Time Distributed Time-Varying Optimization for Nonlinear Fractional-Order Multiagent Systems with Unbalanced Digraphs
title_fullStr Fixed-Time Distributed Time-Varying Optimization for Nonlinear Fractional-Order Multiagent Systems with Unbalanced Digraphs
title_full_unstemmed Fixed-Time Distributed Time-Varying Optimization for Nonlinear Fractional-Order Multiagent Systems with Unbalanced Digraphs
title_short Fixed-Time Distributed Time-Varying Optimization for Nonlinear Fractional-Order Multiagent Systems with Unbalanced Digraphs
title_sort fixed time distributed time varying optimization for nonlinear fractional order multiagent systems with unbalanced digraphs
topic fixed-time distributed optimization
fractional-order multiagent systems
weight-unbalanced digraph
time-varying cost functions
url https://www.mdpi.com/2504-3110/7/11/813
work_keys_str_mv AT kunwang fixedtimedistributedtimevaryingoptimizationfornonlinearfractionalordermultiagentsystemswithunbalanceddigraphs
AT pinggong fixedtimedistributedtimevaryingoptimizationfornonlinearfractionalordermultiagentsystemswithunbalanceddigraphs
AT zhiyaoma fixedtimedistributedtimevaryingoptimizationfornonlinearfractionalordermultiagentsystemswithunbalanceddigraphs