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Extent-compatible control barrier functions Syst. Control Lett. (IF 2.762) Pub Date : 2021-03-01 Mohit Srinivasan; Matthew Abate; Gustav Nilsson; Samuel Coogan
Safety requirements in dynamical systems are commonly enforced with set invariance constraints over a safe region of the state space. Control barrier functions, which are Lyapunov-like functions for guaranteeing set invariance, are an effective tool to enforce such constraints and guarantee safety when the system is represented as a point in the state space. In this paper, we introduce extent-compatible
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Large-scale dynamic system optimization using dual decomposition method with approximate dynamic programming Syst. Control Lett. (IF 2.762) Pub Date : 2021-02-27 Pegah Rokhforoz; Hamed Kebriaei; Majid Nili Ahmadabadi
In this paper, multi-agent dynamic optimization with a coupling constraint is studied. The aim is to minimize a strongly convex social cost function, by considering a linear stochastic dynamics for each agent and also coupling constraints among the agents. In order to handle the coupling constraint and also, to avoid high computational cost imposed by a centralized method for large scale systems, the
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Boundary controllability of phase-transition region of a two-phase Stefan problem Syst. Control Lett. (IF 2.762) Pub Date : 2021-02-27 Viorel Barbu
One proves that the moving interface of a two-phase Stefan problem on Ω⊂Rd, d=1,2,3, is controllable at the end time T by a Neumann boundary controller u. The phase-transition region is a mushy region {σtu;0≤t≤T} of a modified Stefan problem and the main result amounts to saying that, for each Lebesgue measurable set Ω∗ with positive measure, there is u∈L2((0,T)×∂Ω) such that Ω∗⊂σTu. To this aim, one
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Reduced-order fast converging observers for systems with discrete measurements and measurement error Syst. Control Lett. (IF 2.762) Pub Date : 2021-02-26 Frédéric Mazenc; Michael Malisoff; Zhong-Ping Jiang
We provide novel reduced-order observer designs for continuous-time nonlinear systems with measurement error. Our first result applies to systems with continuous output measurements, and provides observers that converge in a fixed finite time that is independent of the initial state when the measurement error is zero. Our second result applies under discrete measurements, and provides observers that
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Port-Hamiltonian formulation of two-phase flow models Syst. Control Lett. (IF 2.762) Pub Date : 2021-02-18 H. Bansal; P. Schulze; M.H. Abbasi; H. Zwart; L. Iapichino; W.H.A. Schilders; N. van de Wouw
Two-phase flows are frequently modelled and simulated using the Two-Fluid Model (TFM) and the Drift Flux Model (DFM). This paper proposes Stokes–Dirac structures with respect to which port-Hamiltonian representations for such two-phase flow models can be obtained. We introduce a non-quadratic candidate Hamiltonian function and present dissipative Hamiltonian representations for both models. We then
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On the robust stability of Volterra differential–algebraic equations Syst. Control Lett. (IF 2.762) Pub Date : 2021-02-18 Nguyen Thu Ha
This paper deals with the robust stability of Volterra differential–algebraic equations. We consider the solvability of the equation and then the preservation of exponential stability under small perturbations. The so-called Bohl–Perron type theorem is also studied.
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Convergence in nonautonomous linear differential equations with Kirchhoff coefficients Syst. Control Lett. (IF 2.762) Pub Date : 2021-02-15 Ábel Garab; Mihály Pituk
A class of nonautonomous linear ordinary differential equations is considered. The coefficient matrices are Metzler matrices with zero column sums such that their directed graphs have a common directed spanning tree. It is shown that if the off-diagonal elements of the coefficients are uniformly positive along the common directed spanning tree, then under mild additional assumptions the convergence
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Event-triggered attitude synchronization of multiple rigid-body systems Syst. Control Lett. (IF 2.762) Pub Date : 2021-02-11 Shimin Wang; Zhan Shu; Tongwen Chen
In this paper, an attitude synchronization problem of multiple rigid-body systems is investigated by using an event-based approach. The leader and followers are described by unit quaternions. A nonlinear distributed observer with event-triggered observations is proposed to estimate the attitude and angular velocity of the leader without continuous information exchange. The triggering mechanism is intermittent
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Approximation and control of a class of distributed delay systems Syst. Control Lett. (IF 2.762) Pub Date : 2021-02-10 Áron Fehér; Lőrinc Márton
In this paper, we show that a linear system with distributed state delay can be approximated by a linear delay-free system that has the same state dimension as the original system if a so-called smallness condition holds. The smallness condition is an inequality which the maximum lag and norms of the system matrices have to satisfy. The eigenvalues of the approximate system correspond to the dominant
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Reinforced adaptive parameter estimation with prescribed transient convergence performance Syst. Control Lett. (IF 2.762) Pub Date : 2021-02-05 Jing Na; Yingbo Huang; Tao Liu; Quanmin Zhu
Although adaptive parameter estimation (APE) has been studied for decades, quantifying the transient estimation error convergence performance (e.g., overshoot and convergence rate) that is essential for system safety and reliability is more difficult than the steady-state convergence analysis. To address this issue, a new APE method with prescribed convergence performance is proposed in this paper
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Boundary Mittag-Leffler stabilization of coupled time fractional order reaction–advection–diffusion systems with non-constant coefficients Syst. Control Lett. (IF 2.762) Pub Date : 2021-01-23 Juan Chen; Aleksei Tepljakov; Eduard Petlenkov; YangQuan Chen; Bo Zhuang
This paper is concerned with boundary control for a class of coupled time fractional order reaction–advection–diffusion (FRAD) systems with non-constant coefficients (space-dependent coefficients) by state feedback. Partial differential equation (PDE) backstepping makes available to stabilize coupled time FRAD systems modeled by fractional PDEs. With boundary controller design and discussion on well-posedness
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Characterization by detectability inequality for periodic stabilization of linear time-periodic evolution systems Syst. Control Lett. (IF 2.762) Pub Date : 2021-01-23 Yashan Xu
Given a linear time-periodic control system in a Hilbert space with a bounded control operator, we present a characterization of periodic stabilization in terms of a detectability inequality. Similar characterization was built up in Trélat et al. (2020), for time-invariant systems.
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H2 suboptimal output synchronization of heterogeneous multi-agent systems Syst. Control Lett. (IF 2.762) Pub Date : 2021-01-23 Junjie Jiao; Harry L. Trentelman; M. Kanat Camlibel
This paper deals with the H2 suboptimal output synchronization problem for heterogeneous linear multi-agent systems. Given a multi-agent system with possibly distinct agents and an associated H2 cost functional, the aim is to design output feedback based protocols that guarantee the associated cost to be smaller than a given upper bound while the controlled network achieves output synchronization.
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Impulse-free interval-stabilization of switched differential algebraic equations Syst. Control Lett. (IF 2.762) Pub Date : 2021-01-23 Paul Wijnbergen; Stephan Trenn
In this paper stabilization of switched differential algebraic equations is considered, where Dirac impulses in both the input and the state trajectory are to be avoided during the stabilization process. First it is shown that stabilizability of a switched DAE and the existence of impulse-free solutions are merely necessary conditions for impulse-free stabilizability. Then necessary and sufficient
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Quantifying ambiguity bounds via time-consistent sets of indistinguishable models Syst. Control Lett. (IF 2.762) Pub Date : 2021-01-23 Anne G. Balter; Antoon Pelsser
Models can be wrong and recognising their limitations is important in financial and economic decision making under uncertainty. Robust strategies, which are least sensitive to perturbations of the underlying model, take uncertainty into account. Interpreting the explicit set of alternative models surrounding the baseline model has been difficult so far. We specify alternative models via a time-consistent
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Stochastic maximum principle of mean-field jump–diffusion systems with mixed delays Syst. Control Lett. (IF 2.762) Pub Date : 2021-01-21 Feng Zhang
This paper is concerned with one kind of stochastic optimal control problem of mean-field jump–diffusion system with moving-average as well as pointwise delays. By means of the maximum principle, both necessary and sufficient optimality conditions are established. Two kinds of adjoint equations are used, which are shown to be equivalent. That is, a unified adjoint equation is provided.
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Logical matrix factorization towards topological structure and stability of probabilistic Boolean networks Syst. Control Lett. (IF 2.762) Pub Date : 2021-01-21 Yuna Liu; Haitao Li
The study of logical matrix factorization provides a new insight into the matrix dimension reduction problems of biological systems. This paper develops the logical matrix factorization technique for exploring the topological structure and stability of probabilistic Boolean networks (PBNs). Firstly, the union set of distinct indices in factorized structural matrices for different modes is obtained
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Regularized stochastic team problems Syst. Control Lett. (IF 2.762) Pub Date : 2021-01-22 Naci Saldi
In this paper, we introduce regularized stochastic team problems. Under mild assumptions, we prove that there exists a unique fixed point of the best response operator, where this unique fixed point is the optimal regularized team decision rule. Then, we establish an asynchronous distributed algorithm to compute this optimal strategy. We also provide a bound that shows how the optimal regularized team
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Secure and privacy preserving consensus for second-order systems based on Paillier encryption Syst. Control Lett. (IF 2.762) Pub Date : 2021-01-16 Wentuo Fang; Mohsen Zamani; Zhiyong Chen
This paper aims at secure and privacy-preserving consensus algorithms of networked systems. Due to the technical challenges behind decentralized design of such algorithms, the existing results are mainly restricted to a network of systems with simplest first-order dynamics. Like many other control problems, breakthrough of the gap between first-order dynamics and higher-order ones demands for more
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On the use of low-pass filters in high-gain observers Syst. Control Lett. (IF 2.762) Pub Date : 2021-01-11 Daniele Astolfi; Luca Zaccarian; Marc Jungers
To address the well-known noise sensitivity problems associated with high-gain observers, we insert a low-pass filter on the measurement channel. Considering nonlinear plants in observability canonical form, we first motivate an architecture where the output error is filtered by a linear system parametrized by its arbitrary order and a scalar positive gain. Our main result establishes an exponential
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Differential dissipativity analysis of reaction–diffusion systems Syst. Control Lett. (IF 2.762) Pub Date : 2021-01-09 Félix A. Miranda-Villatoro; Rodolphe Sepulchre
This note shows how classical tools from linear control theory can be leveraged to provide a global analysis of nonlinear reaction–diffusion models. The approach is differential in nature. It proceeds from classical tools of contraction analysis and recent extensions to differential dissipativity.
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Bayesian positive system identification: Truncated Gaussian prior and hyperparameter estimation Syst. Control Lett. (IF 2.762) Pub Date : 2021-01-08 Man Zheng; Yoshito Ohta
Bayesian methods have been extended for the linear system identification problem in the past ten years. The traditional Bayesian identification selects a Gaussian prior and considers the tuning of kernels, i.e., the covariance matrix of a Gaussian prior. However, Gaussian priors cannot express the system information appropriately for identifying a positive finite impulse response (FIR) model. This
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Null-controllability of linear hyperbolic systems in one dimensional space Syst. Control Lett. (IF 2.762) Pub Date : 2021-01-09 Jean-Michel Coron; Hoai-Minh Nguyen
This paper is devoted to the controllability of a general linear hyperbolic system in one space dimension using boundary controls on one side. Under precise and generic assumptions on the boundary conditions on the other side, we previously established the optimal time for the null and the exact controllability for this system for a generic source term. In this work, we prove the null-controllability
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Global attracting sets and exponential stability of stochastic partial functional differential equations Syst. Control Lett. (IF 2.762) Pub Date : 2021-01-06 Zhi Li; Liping Xu; Liguang Xu
This paper is concerned with the global attracting sets and the exponential stability in the mean square of mild solutions for stochastic functional partial differential equations. Some new sufficient conditions ensuring the existence of the global attracting sets and the exponential stability in the mean square of mild solutions for the considered equations are established by introducing approximating
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Strategic sensor placement on graphs Syst. Control Lett. (IF 2.762) Pub Date : 2021-01-04 Mohammad Pirani; Joshua A. Taylor; Bruno Sinopoli
This paper studies optimal sensor placement in networked control systems for improving the detectability of cyber–physical attacks. The problem is formulated as a game between an attacker and a detector. The attacker’s decision is to select a set of nodes in the network to attack, and the detector’s decision is to places sensors on a set of nodes. The detector tries to maximize the detectability of
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Homogeneous Lyapunov functions for homogeneous infinite dimensional systems with unbounded nonlinear operators Syst. Control Lett. (IF 2.762) Pub Date : 2021-01-02 Andrey Polyakov
The existence of a locally Lipschitz continuous homogeneous Lyapunov function is proven for a class of asymptotically stable homogeneous infinite dimensional systems with unbounded nonlinear operators.
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Neural network based nonlinear observers Syst. Control Lett. (IF 2.762) Pub Date : 2021-01-01 Tobias Breiten; Karl Kunisch
Nonlinear observers based on the well-known concept of minimum energy estimation are discussed. The approach relies on an output injection operator determined by a Hamilton–Jacobi–Bellman equation whose solution is subsequently approximated by a neural network. A suitable optimization problem allowing to learn the network parameters is proposed and numerically investigated for linear and nonlinear
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Game-based coalescence in multi-agent systems Syst. Control Lett. (IF 2.762) Pub Date : 2020-12-28 Jingying Ma; Yuanshi Zheng; Likai Zhou
Agents are normally designed to be self-interested and tend to maximize their own interests in many realistic systems, such as robotics, smart grids and autonomous vehicles. In this paper, we propose a model of repeated bimatrix game to study the ubiquitous group behavior, coalescence, in multi-agent systems, where different agents form a union and keep consensus in states. We find that whether the
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Control and inverse problems for the heat equation with strong singularities Syst. Control Lett. (IF 2.762) Pub Date : 2020-12-26 Sergei Avdonin; Nina Avdonina; Julian Edward; Karlygash Nurtazina
We consider a linear system composed of N+1 one dimensional heat equations connected by point-mass-like interface conditions. Assume an L2 Dirichlet boundary control at one end, and Dirichlet boundary condition on the other end. Given any L2-type initial temperature distribution, we show that the system is null controllable in arbitrarily small time. The proof uses known results for exact controllability
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Global exponential stability and Input-to-State Stability of semilinear hyperbolic systems for the L2 norm Syst. Control Lett. (IF 2.762) Pub Date : 2020-12-25 Amaury Hayat
In this paper we study the global exponential stability in the L2 norm of semilinear 1-d hyperbolic systems on a bounded domain, when the source term and the nonlinear boundary conditions are Lipschitz. We exhibit two sufficient stability conditions: an internal condition and a boundary condition. This result holds also when the source term is nonlocal. Finally, we show its robustness by extending
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New results and examples in semiglobal asymptotic stabilization of nonaffine systems by sampled-data output feedback Syst. Control Lett. (IF 2.762) Pub Date : 2020-12-24 Wei Lin; Jiwei Sun
For a class of SISO non-affine systems, we address the problem of how semiglobal asymptotic stabilization (SGAS) can be achieved by n-dimensional sampled-data output feedback. The new result of this paper gives a partial answer to the open question in the recent work Lin (2020), where (2n−1)-dimensional output feedback controllers were designed based on the dynamic extension method.
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Data-based and secure switched cyber–physical systems Syst. Control Lett. (IF 2.762) Pub Date : 2020-12-24 Lijing Zhai; Kyriakos G. Vamvoudakis
In this paper, we develop a completely model-free moving target defense framework for the detection and mitigation of sensor and/or actuator attacks in cyber–physical systems with dynamics that evolve in discrete-time. We incorporate an intrusion detection mechanism based on an approximate dynamic programming technique that learns the policies for optimal regulation and optimal tracking while simultaneously
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Structured identification for network reconstruction of RC-models Syst. Control Lett. (IF 2.762) Pub Date : 2020-12-17 Gabriele Calzavara; Luca Consolini; Juxhino Kavaja
Resistive–capacitive (RC) networks are used to model various processes in engineering, physics or biology. We consider the problem of recovering the network connection structure from measured input–output data. We address this problem as a structured identification one, that is, we assume to have a state-space model of the system (identified with standard techniques, such as subspace methods) and find
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Dissipativity learning control (DLC): Theoretical foundations of input–output data-driven model-free control Syst. Control Lett. (IF 2.762) Pub Date : 2020-12-14 Wentao Tang; Prodromos Daoutidis
Data-driven, model-free control strategies leverage statistical or learning techniques to design controllers based on data instead of dynamic models. We have previously introduced the dissipativity learning control (DLC) method, where the dissipativity property is learned from the input–output trajectories of a system, based on which L2-optimal P/PI/PID controller synthesis is performed. In this work
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L2-incremental gain stability of linear systems with nonlinear Lipschitz actuator Syst. Control Lett. (IF 2.762) Pub Date : 2020-12-11 Mohsen Ghodrat; Horacio J. Marquez
In this manuscript we study the problem of finding incremental L2-gain of a class of nonlinear systems obtained by combining a linear plant and a general dynamic controller and a nonlinear actuator. The proposed method allows for the existence of possible nonlinear imperfections in the actuator. The justification of the proposed approach is provided through a compelling example.
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Inventory control of a class of logistic networks Syst. Control Lett. (IF 2.762) Pub Date : 2020-12-09 Berna Bou Farraa; Rosa Abbou; Jean Jacques Loiseau
This paper focuses on a prediction-based control for a class of convolution systems subject to constant input delays, also known as the reduction approach. We propose here a characterization of the D-invariance property of polytope sets for continuous-time systems. Our motivations come from production management, where a general model for a production network is considered. The system is subject to
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Generalized value iteration for discounted optimal control with stability analysis Syst. Control Lett. (IF 2.762) Pub Date : 2020-12-08 Mingming Ha; Ding Wang; Derong Liu
In this work, the generalized value iteration with a discount factor is developed for optimal control of discrete-time nonlinear systems, which is initialized with a positive definite value function rather than zero. The convergence analysis of the discounted value function sequence is provided. The condition for the discount factor is given to guarantee the stability of the controlled plants. With
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Minimax sliding mode control design for linear evolution equations with noisy measurements and uncertain inputs Syst. Control Lett. (IF 2.762) Pub Date : 2020-12-08 Sergiy Zhuk; Orest V. Iftime; Jonathan P. Epperlein; Andrey Polyakov
We extend a sliding mode control methodology to linear evolution equations with uncertain but bounded inputs and noise in observations. We first describe the reachability set of the state equation in the form of an infinite-dimensional ellipsoid, and then steer the minimax center of this ellipsoid toward a finite-dimensional sliding surface in finite time by using the standard sliding mode output-feedback
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Node and network resistance to bribery in multi-agent systems Syst. Control Lett. (IF 2.762) Pub Date : 2020-12-07 Guilherme Ramos; Daniel Silvestre; Carlos Silvestre
In this paper, we propose a framework to study the resistance to bribery of nodes in a network via average consensus. We extend the proposed bribery resistance measure to sets of nodes, and networks. The proposed framework evaluates quantitatively how much an external entity needs to drive the state of an agent away from its current state, to change the final consensus value. Subsequently, we illustrate
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Stabilization and optimal control of discrete-time systems with multiplicative noise and multiple input delays Syst. Control Lett. (IF 2.762) Pub Date : 2020-12-04 Lin Li; Huanshui Zhang; Yu Wang
This paper is concerned with the stabilization and optimal control of discrete-time systems with multiplicative noise and multiple input delays. First, it is shown that the systems are stabilizable if and only if some algebraic Riccati-type equations have a solution which satisfies a given condition. To the best of our knowledge, this is the first time to propose a necessary and sufficient stabilizing
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Stability radii of differential–algebraic equations with respect to stochastic perturbations Syst. Control Lett. (IF 2.762) Pub Date : 2020-12-04 Do Duc Thuan; Nguyen Hong Son; Cao Thanh Tinh
In this paper, we investigate differential–algebraic equations (DAEs) subject to stochastic perturbations. We introduce the index-ν concept and establish a formula of solution for these equations. After that the stability is studied by using the method of Lyapunov functions. Finally, the robust stability of DAEs with respect to stochastic perturbations is considered. Formulas of the stability radii
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Completely distributed formation control for networked quadrotors under switching communication topologies Syst. Control Lett. (IF 2.762) Pub Date : 2020-12-03 Hao Liu; Yanhu Wang; Jianxiang Xi
This paper investigates a completely distributed adaptive formation control protocol for networked quadrotors under switching communication topologies, where the dynamics of each quadrotor involves seriously nonlinearity and uncertainty simultaneously. For the switching communication topologies case, the adaptive formation control protocol is proposed to guarantee that the translational and rotational
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On the existence of a common Lyapunov function for a family of nonlinear positive systems Syst. Control Lett. (IF 2.762) Pub Date : 2020-12-02 Alexander Aleksandrov
This paper is devoted to the stability analysis of a class of switched nonlinear positive systems with nonlinearities of a sector type. A special construction of common Lyapunov function is proposed for the family of subsystems associated with a switched system and conditions of the existence of such a function are derived. The obtained results are used for the absolute stability investigation of switched
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Stabilization of bilateral teleoperators with asymmetric stochastic delay Syst. Control Lett. (IF 2.762) Pub Date : 2020-12-01 Francesco Cordoni; Luca Di Persio; Riccardo Muradore
In this paper we consider the problem of position tracking and error boundedness for a master–slave teleoperation system when the communication channel is characterized by a time-varying stochastic delay. In particular, we assume the delay to be a time-varying Markov regime switching process. Our solution is based on a suitable proportional–derivative (PD) like controller. Exploiting a Lyapunov–Krasovskii
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Well-posedness and exponential stability of boundary control systems with dynamic boundary conditions Syst. Control Lett. (IF 2.762) Pub Date : 2020-11-28 Abed Boulouz; Hamid Bounit; Said Hadd
The well-posedness of abstract boundary control systems with dynamic boundary conditions (i.e., boundary conditions evolving according to an operator semigroup acting on the boundary space) is established . Here, the boundary feedback operator is unbounded which makes the investigation more interesting in many applications. The positivity of such problem is well studied. By exploiting the positivity
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Passive linear continuous-time systems: Characterization through structure Syst. Control Lett. (IF 2.762) Pub Date : 2020-11-27 Izchak Lewkowicz
We here show that the family of finite-dimensional, continuous-time, passive, linear, time-invariant systems can be characterized through the structure of maximal matrix-convex cones, closed under inversion. Moreover, this observation unifies three setups: (i) differential inclusions, (ii) matrix-valued rational functions, (iii) realization arrays associated with rational functions. It turns out that
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Generating series for networks of Chen–Fliess series Syst. Control Lett. (IF 2.762) Pub Date : 2020-11-23 W. Steven Gray; Kurusch Ebrahimi-Fard
Consider a set of single-input, single-output nonlinear systems whose input–output maps are described only in terms of convergent Chen–Fliess series without any assumption that finite dimensional state space models are available. It is shown that any additive or multiplicative interconnection of such systems always has a Chen–Fliess series representation that can be computed explicitly in terms of
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Fully distributed time-varying formation tracking control of linear multi-agent systems with input delay and disturbances Syst. Control Lett. (IF 2.762) Pub Date : 2020-11-19 Wei Jiang; Chunyan Wang; Yunhe Meng
This paper investigates the time-varying formation tracking (TVFT) control problem considering a constant input delay and unknown external disturbances for the general linear multi-agent system (MAS) under a directed communication graph containing a spanning tree. To achieve that, a new time-varying shape format is firstly proposed. Then, a disturbance observer (DO) is introduced to compensate the
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Local R-linear convergence of ADMM-based algorithm for ℓ1-norm minimization with linear and box constraints Syst. Control Lett. (IF 2.762) Pub Date : 2020-11-17 Mitsuru Toyoda; Mirai Tanaka
This paper presents an efficient algorithm based on the alternating direction method of multipliers (ADMM) for an ℓ1-norm minimization problem with linear equality and box constraints. In the ADMM iterations, sub-problems, called proximal minimizations, are solved to obtain the next updating points by exploiting closed formulae. Furthermore, the local R-linear convergence is established by analysis
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Orbital Stabilization of Underactuated Systems using Virtual Holonomic Constraints and Impulse Controlled Poincaré Maps Syst. Control Lett. (IF 2.762) Pub Date : 2020-11-13 Nilay Kant; Ranjan Mukherjee
The problem of orbital stabilization of underactuated mechanical systems with one passive degree-of-freedom (DOF) is revisited. Virtual holonomic constraints are enforced using a continuous controller; this results in a dense set of closed orbits on a constraint manifold. A desired orbit is selected on the manifold and a Poincaré section is constructed at a fixed point on the orbit. The corresponding
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Optimal linear–quadratic control of asymptotically stabilizable systems using approximations Syst. Control Lett. (IF 2.762) Pub Date : 2020-11-13 Hans Zwart; Kirsten A. Morris; Orest V. Iftime
In this paper we study approximations to the infinite-horizon quadratic optimal control problem for linear systems that may be only asymptotically stabilizable. For linear systems, this issue only arises with infinite-dimensional systems. We provide sufficient conditions which guarantee when approximations to the optimal feedback result in the cost converging to the optimal cost. One technique for
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Boundary feedback stabilization of quasilinear hyperbolic systems with partially dissipative structure Syst. Control Lett. (IF 2.762) Pub Date : 2020-11-10 Ke Wang; Zhiqiang Wang; Wancong Yao
In this paper, we study the boundary feedback stabilization of a quasilinear hyperbolic system with partially dissipative structure. Thanks to this structure, we construct a suitable Lyapunov function which leads to the exponential stability to the equilibrium of the H2 solution. As an application, we also obtain the feedback stabilization for the Saint-Venant-Exner model under physical boundary conditions
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On the fixed-time stabilization of input delay systems using act-and-wait control Syst. Control Lett. (IF 2.762) Pub Date : 2020-11-04 Wim Michiels; Bin Zhou
We address the state feedback stabilization of linear systems with input delay using the so-called act-and-wait control strategy. The latter approach induces an analysis of the closed-loop stability based on a finite-dimensional monodromy operator, and rendering this matrix nilpotent results in fixed-time stability. We show that any controllable planar system can be stabilized in a fixed time, and
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A stochastic maximum principle for partially observed stochastic control systems with delay Syst. Control Lett. (IF 2.762) Pub Date : 2020-11-03 Shuaiqi Zhang; Xun Li; Jie Xiong
This paper deals with partially-observed optimal control problems for the state governed by stochastic differential equation with delay. We develop a stochastic maximum principle for this kind of optimal control problems using a variational method and a filtering technique. Also, we establish a sufficient condition without assumption of the concavity. Two examples that shed light on the theoretical
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ISS-like estimates for nonlinear parabolic PDEs with variable coefficients on higher dimensional domains Syst. Control Lett. (IF 2.762) Pub Date : 2020-10-21 Jun Zheng; Guchuan Zhu
This paper presents a maximum principle-based approach in the establishment of ISS-like estimates for a class of nonlinear parabolic partial differential equations (PDEs) with variable coefficients and different types of nonlinear boundary conditions on higher dimensional domains. Comparing with the existing literature, the ISS-like estimates established in this paper are independent of the nonlinear
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Hybrid boundary stabilization of linear first-order hyperbolic PDEs despite almost quantized measurements and control input Syst. Control Lett. (IF 2.762) Pub Date : 2020-10-26 Nikolaos Bekiaris-Liberis
We develop a hybrid boundary feedback law for a class of scalar, linear, first-order hyperbolic PDEs, for which the state measurements or the control input are subject to quantization. The quantizers considered are Lipschitz functions, which can approximate arbitrarily closely typical piecewise constant, taking finitely many values, quantizers. The control design procedure relies on the combination
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Robustification of nonlinear control systems vis-à-vis actuator dynamics: An immersion and invariance approach Syst. Control Lett. (IF 2.762) Pub Date : 2020-10-27 Romeo Ortega; Bowen Yi; Jose Guadalupe Romero
In this brief note we pose, and solve, the problem of robustification of controller designs where the actuator dynamics was neglected. This situation is very common in applications where, to validate the assumption that the actuator dynamics can be neglected, a high-gain inner-loop that enforces a time-scale separation between the actuator and the plant dynamics is implemented. Of course, the injection
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Adaptive synchronization of heterogeneous multi-agent systems: A free observer approach Syst. Control Lett. (IF 2.762) Pub Date : 2020-10-15 Miguel F. Arevalo-Castiblanco; Duvan Tellez-Castro; Jorge Sofrony; Eduardo Mojica-Nava
Adaptive synchronization protocols for heterogeneous multi-agent network are investigated. The interaction between each of the agents is carried out through a directed graph. We highlight the lack of communication between agents and the presence of uncertainties in each system among the conventional problems that can arise in cooperative networks. Two methodologies are presented to deal with the uncertainties:
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Generalized weak rigidity: Theory, and local and global convergence of formations Syst. Control Lett. (IF 2.762) Pub Date : 2020-10-12 Seong-Ho Kwon; Hyo-Sung Ahn
This paper proposes a generalized weak rigidity theory, and aims to apply the theory to formation control problems with a gradient descent flow law. The generalized weak rigidity theory is utilized in order to characterize desired rigid formations by a general set of pure inter-agent distances and subtended angles, where the rigid formation shape with distances and subtended angles is determined up
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Optimal output estimation for infinite-dimensional systems with disturbances Syst. Control Lett. (IF 2.762) Pub Date : 2020-10-12 Kirsten A. Morris
Often only some aspect of the state needs to be estimated, not the whole state. This problem is referred to as output estimation Also, there may be disturbances other than Gaussian noise. In such situations a Kalman filter may not be the most appropriate estimator. Two alternative approaches are to reduce the H2 or H∞ output estimation error. A derivation of both types of estimators for output estimation
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