Article
Automation & Control Systems
Alessandro Borri, Pierdomenico Pepe
Summary: This article presents a method for event-triggered stabilization of nonlinear time-delay systems, utilizing control Lyapunov-Razumikhin functions and a spline-based approximation of functional state feedback to achieve a finite-memory controller, ensuring positive minimal interevent time while avoiding continuous-state monitoring. Application examples demonstrate the potential of this approach.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2021)
Article
Automation & Control Systems
Xian Yang, Jing Yan, Changchun Hua, Xinping Guan
Summary: Bilateral teleoperation system is a promising technology to extend human actions and intelligence to remote manipulation. This paper provides a solution to the real-time tracking issue of teleoperation systems with unavailable velocity signals and time-varying communication delays. By employing the immersion and invariance (I & I) technique, an exponential stability velocity observer is developed to estimate the velocity information. A slave-torque feedback control law is presented based on the estimated velocity information. Simulation and experimental results demonstrate that the proposed observer and controller can ensure error convergence to zero.
IEEE-CAA JOURNAL OF AUTOMATICA SINICA
(2023)
Article
Automation & Control Systems
Zhichuang Wang, Jian Sun, Jie Chen
Summary: This article addresses the stability problem of switched nonlinear systems with multiple time-varying delays using multiple Lyapunov-Krasovskii functionals technique and T-S fuzzy models. A novel switching signal is developed to eliminate the effect of the increment energy of Lyapunov functions for unstable modes, and the effectiveness of the method is validated through numerical simulations.
IEEE TRANSACTIONS ON SYSTEMS MAN CYBERNETICS-SYSTEMS
(2022)
Article
Automation & Control Systems
Qiang Xiao, Zhenkun Huang, Zhigang Zeng, Tingwen Huang, Frank L. Lewis
Summary: This note focuses on the stability analysis of positive homogeneous nonlinear systems with bounded time-varying delays. It extends previous results by studying the exponential stability of a class of delayed homogeneous systems with degree confined to an interval based on the positivity property. The state boundary of the system at any fixed time is further investigated, providing more precise results in some cases. Finite-time stability is also obtained for a delay-free homogeneous system, along with an explicit boundary.
Article
Automation & Control Systems
Stephen Arockia Samy, Yang Cao, Raja Ramachandran, Jehad Alzabut, Michal Niezabitowski, Chee Peng Lim
Summary: This article investigates the global asymptotic stability and synchronization analysis of uncertain multi-agent systems with multiple time-varying delays and impulsive perturbations. Through mathematical proofs, the existence and uniqueness of equilibrium points are established, and a pining control strategy is designed to achieve global asymptotic stability and synchronization. Numerical calculations and simulations are provided to verify the theoretical findings.
INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL
(2022)
Article
Computer Science, Artificial Intelligence
Hao Zhang, Zhigang Zeng
Summary: This article investigates the stability and synchronization of nonautonomous reaction-diffusion neural networks with general time-varying delays. By establishing easily checkable criteria through Green's formula and analytical techniques, the obtained results not only improve existing ones but also contain novel results. The effectiveness and superiorities of the established criteria are verified by three numerical examples.
IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS
(2022)
Article
Automation & Control Systems
Huitao Yang, Yu Zhang, Xiangming Zhang, Shanshan Hong
Summary: This paper investigates the positivity and stability of discrete-time coupled homogeneous systems with time-varying delays. By providing explicit criterion for positivity and using the properties of homogeneous functions, a sufficient condition for ensuring the stability is presented. The obtained result is applied to study the stability of positive singular systems with time-varying delay for the first time.
JOURNAL OF THE FRANKLIN INSTITUTE-ENGINEERING AND APPLIED MATHEMATICS
(2022)
Article
Computer Science, Artificial Intelligence
Hong Cheng, Xiucai Huang, Hongwei Cao
Summary: This paper proposes a method to achieve asymptotic tracking control for uncertain nonlinear strict-feedback systems with unknown time-varying delays and unknown control direction. The Lyapunov-Krasovskii functional is used to deal with the time delays, and the neural network is applied to compensate for the unknown terms arising from the derivative of the Lyapunov-Krasovskii functional. An NN-based adaptive control scheme is constructed based on backstepping technique, and the output tracking error is ensured to converge to zero asymptotically. The proposed method settles the singularity issue commonly encountered in coping with time delay problems and improves the transient performance with proper choice of design parameters.
IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS
(2023)
Article
Automation & Control Systems
Filippo Cacace, Alfredo Germani, Costanzo Manes
Summary: This article proposes an improved observer for Lipschitz nonlinear systems with time-varying and known measurement delays, achieving exponential convergence to zero of observation error with any desired decay rate by tuning a gain vector. The delay bound obtained with this observer is less conservative than previous methods, as confirmed by numerical tests. While only one-step observers are considered in this study, a cascade observer can be arranged to handle arbitrarily long delays.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2021)
Article
Mathematics
Chao Liu, Xiaoyang Liu
Summary: This paper studies the stability of linear switched systems with time-varying delays and all unstable subsystems. It proposes a state-dependent switching rule based on the largest region function strategy. By introducing integral inequality and multiple Lyapunov-Krasovskii functionals, the stability results of delayed switched systems are derived under the designed switching rule for different assumptions on time delay. Numerical examples are provided to demonstrate the effectiveness and superiority of the proposed results.
Article
Engineering, Mechanical
Yao Wang, Shengyuan Xu, Junwei Lu, Zhengqiang Zhang
Summary: This paper addresses the issue of finite-time observer-based control for continuous-time nonlinear Markovian jump systems with time-varying delays. It introduces a method where the modes of observer and controller are supposed to be asynchronous with the modes of the original system simultaneously. By constructing novel Lyapunov-Krasovskii functionals and using finite-time analysis theory, the error system is proven to be finite-time bounded with an H-infinity performance level, and parameters for the desired observer and controller are calculated using linear matrix inequalities. Numerical examples are provided to demonstrate the proposed method's lesser conservativeness and higher effectiveness.
NONLINEAR DYNAMICS
(2021)
Article
Automation & Control Systems
Wenjie Li, Zhengqiang Zhang
Summary: This paper addresses the asymptotic stabilization problem for a class of nonlinear systems with unknown time-varying delays and develops a novel output feedback control strategy. The effectiveness of this method is validated through numerical simulation.
IET CONTROL THEORY AND APPLICATIONS
(2023)
Article
Mathematics
Xikui Liu, Wencong Li, Chenxin Yao, Yan Li
Summary: This paper addresses the finite-time guaranteed cost control problem for Ito Markovian jump systems with time-varying delays. It presents new sufficient conditions for the existence of guaranteed cost controllers using the linear matrix inequality approach. Based on these conditions, the desired controllers are designed and the upper bound of cost performance is provided. An example is employed to demonstrate the validity of the obtained results.
Article
Automation & Control Systems
Filippo Cacace, Francesco Conte, Massimiliano d'Angelo, Alfredo Germani, Giovanni Palombo
Summary: In this paper, we tackle the estimation problem in linear stochastic systems with multiple known and time-varying delays on all output signals. By modifying a previous proposal, we for the first time prove that a filter based on simple eigenvalue assignment of the closed-loop error system can achieve uniform performance in the presence of both constant and differentiable time-varying delays, with respect to the delay bound and estimation variance. We also introduce a new and simple demonstration technique that provides non-conservative delay bounds for time-varying delays. Additionally, a cascaded version of the filter can handle arbitrarily large delays.
Article
Automation & Control Systems
Peng Wan, Zhigang Zeng
Summary: This article focuses on the impulsive stabilization of nonautonomous timescale-type neural networks with constant and unbounded time-varying delays. Several algebraic criteria are demonstrated to achieve globally asymptotic stabilization, and impulsive control schemes are proposed for both constant and unbounded delay cases. The theoretical results are verified through numerical examples.
IEEE TRANSACTIONS ON SYSTEMS MAN CYBERNETICS-SYSTEMS
(2023)
Article
Physics, Multidisciplinary
Rico Berner, Simon Vock, Eckehard Schoell, Serhiy Yanchuk
Summary: The study developed a master stability approach for a wide class of adaptive networks, simplifying the synchronization problem to a low-dimensional system and revealing the interplay between adaptivity and network structure in the formation of stability islands and complex synchronization patterns.
PHYSICAL REVIEW LETTERS
(2021)
Article
Mathematics, Applied
Vander L. S. Freitas, Serhiy Yanchuk, Michael Zaks, Elbert E. N. Macau
Summary: The study has shown that autonomous mobile agents can form symmetric clusters in specific regions of parameter space and proposes a strategy for switching formation modes. In addition, a method for obtaining chaotic almost-circular trajectories and symmetric clusters with non-overlapping particles is introduced.
COMMUNICATIONS IN NONLINEAR SCIENCE AND NUMERICAL SIMULATION
(2021)
Article
Mathematics, Applied
Y. Liu, J. Paez Chavez, P. Brzeski, P. Perlikowski
Summary: This paper investigates the complex dynamical behavior of a rigid block structure under harmonic ground excitation, and studies its response in detail using numerical integration and path-following techniques. Various dynamical phenomena are revealed, and the properties of solutions and their ranges of existence are explored using the basin stability method.
Article
Mathematics
Serhiy Yanchuk, Matthias Wolfrum, Tiago Pereira, Dmitry Turaev
Summary: This paper presents criteria for the absolute stability of delay differential equations (DDEs) with discrete time-delays and establishes the equivalence between absolute stability and asymptotic stability for different delay scenarios. The necessary and sufficient conditions for a linear DDE to be hyperbolic for all delays are also provided, which are crucial for understanding bifurcations caused by varying time delays.
JOURNAL OF DIFFERENTIAL EQUATIONS
(2022)
Editorial Material
Neurosciences
Joana Cabral, Viktor Jirsa, Oleksandr V. Popovych, Alessandro Torcini, Serhiy Yanchuk
FRONTIERS IN SYSTEMS NEUROSCIENCE
(2022)
Review
Mathematics, Applied
Maciej Leszczynski, Przemyslaw Perlikowski, Tomasz Burzynski, Tomasz M. Kowalski, Piotr Brzeski
Summary: Sample-based methods are useful tools for analyzing the behavior of multi-stable systems. Traditional methods often fail to analyze complex systems with multiple coexisting attractors. Each sample-based method has specific properties and advantages, but none of them provide complete information. Therefore, data from multiple methods are necessary to obtain a comprehensive understanding of the dynamics of a system.
Article
Mechanics
Konrad Mnich, Mateusz Lazarek, Andrzej Stefanski, Przemyslaw Perlikowski
Summary: This paper presents a study on the experimental identification of the friction force in the inerter with constant and variable inertance. By conducting experiments and creating models, precise modeling of devices equipped with inerters can be achieved.
Article
Engineering, Mechanical
M. Lazarek, P. Brzeski, P. Perlikowski
Summary: This paper presents the dynamical modeling and efficacy assessment of a planetary variator in a tuned mass damper with a variable inerter. The off-the-shelf planetary variator is modified and its kinematic and dynamic models are developed and experimentally validated. The modified device is implemented in the tuned mass damper as part of a system to control vibration in a wide range of excitation frequencies.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2022)
Article
Engineering, Mechanical
Tomasz Burzynski, Przemyslaw Perlikowski, Marek Balcerzak, Piotr Brzeski
Summary: This paper investigates the dynamics of swinging bells in the design and monitoring of the bell's supporting structures. A novel yoke-bell-clapper system with variable geometry and adjustable excitation force is introduced and a mathematical model based on an existing prototype is validated. The impact of yoke geometry and excitation force on the system response is evaluated through simulations. The derived mathematical model can accurately predict the ringing scheme and reaction forces in the supports of the bell.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2022)
Article
Engineering, Mechanical
Daniel Maia, Juergen Kurths, Serhiy Yanchuk
Summary: This paper considers the synchronization problem of dynamical networks with delayed interactions. The focus is on stabilizing synchronous equilibria in regular networks with equal degrees of all nodes. Necessary and sufficient conditions for stabilization are obtained by studying such control near a Hopf bifurcation. It is found that the stabilization domains in the parameter space reappear periodically with time-delay, and the frequency of reappearance is linearly proportional to the number of cycle multipartitions of the network.
NONLINEAR DYNAMICS
(2023)
Article
Engineering, Civil
Tomasz Kubiak, Lukasz Borkowski, Przemyslaw Perlikowski
Summary: This paper investigates the response of thin orthotropic square plates subjected to in-plane time-dependent compressive load related to static buckling load. The plate behavior under dynamic load is analyzed using phase portraits, Poincare maps, and Lyapunov exponents. The research aims to check the feasibility of using stability analysis methods for rigid body motion in dynamic buckling determinations and dynamic response analysis of thin-walled deformable structures.
THIN-WALLED STRUCTURES
(2023)
Article
Mathematics, Applied
Max Thiele, Rico Berner, Peter A. A. Tass, Eckehard Schoell, Serhiy Yanchuk
Summary: This study presents a framework for describing the emergence of recurrent synchronization in complex networks with adaptive interactions. The phenomenon is manifested by temporal episodes of coherent and incoherent dynamics that alternate recurrently. Asymmetric adaptation rules and temporal separation between adaptation and individual node dynamics are identified as key features for the emergence of recurrent synchronization.
Article
Computer Science, Artificial Intelligence
Felix Koester, Serhiy Yanchuk, Kathy Ludge
Summary: This study demonstrates that delay-based reservoir computers can be characterized by a universal master memory function (MMF) and provides linear memory capacity. An analytical description of the MMF is proposed for efficient computing and can be applied to various reservoir scenarios.
IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS
(2022)
Article
Mathematics, Applied
Matthias Wolfrum, Serhiy Yanchuk, Otti D'Huys
Summary: In this study, the mechanisms for the appearance of multiple coexisting partially locked states in the Kuramoto-Sakaguchi system were fully analytically explained, along with the stability characteristics of these states and the role of the Sakaguchi phase lag parameter under different delay conditions.
SIAM JOURNAL ON APPLIED DYNAMICAL SYSTEMS
(2022)
Article
Mathematics, Applied
Rico Berner, Volker Mehrmann, Eckehard Schoell, Serhiy Yanchuk
Summary: Multiplex networks consist of multiple layers with the same number of nodes and diagonal adjacency matrices between layers. This study focuses on a special class of multiplex networks where adjacency matrices for each layer can be simultaneously triangularized. A generalized master stability approach is proposed for a simplified description of stability of synchronized solutions in multiplex networks.
SIAM JOURNAL ON APPLIED DYNAMICAL SYSTEMS
(2021)
