The robustness properties of integral sliding-mode controllers are studied. This note shows how to select the projection matrix in such a way that euclidean norm resulting perturbation is minimal. It also shown when minimum attained, not amplified. selection particularly useful if control be combined with other methods further robustify against unmatched perturbations. H/sub /spl infin// taken as special case. Simulations support general analysis and show effectiveness this particular combination.

The dynamics of many physical processes can be suitably described by Port-Hamiltonian (PH) models, where the importance energy function, interconnection pattern and dissipation system is underscored. To regulate behavior PH systems it natural to adopt a Passivity-Based Control (PBC) perspective, control objectives are achieved shaping function adding dissipation. In this paper we consider PBC techniques Interconnection ( <i xmlns:mml="http://www.w3.org/1998/Math/MathML"...

We consider the problem of designing an integral sliding mode controller to reduce disturbance terms that act on nonlinear systems with state-dependent drift and input matrix. The general case both, matched unmatched disturbances affecting system is addressed. It proved definition a suitable manifold generation modes upon it guarantees minimization effect terms, which takes place when are completely rejected ones not amplified. A simulation proposed technique, applied dynamically feedback...

For mitigating the COVID-19 pandemic, much emphasis is made on implementing non-pharmaceutical interventions to keep reproduction number below one. However, using that objective ignores some of these interventions, like bans public events or lockdowns, must be transitory and as short possible because their significant economic societal costs. Here, we derive a simple mathematically rigorous criterion for designing optimal epidemic outbreaks. We find reducing one sufficient but not necessary....

The robust trajectory tracking of fully actuated Lagrange systems is studied. Exogenous perturbations as well parameter uncertainties are taken into account. A family set-valued passivity-based controllers proposed, including first-order sliding-mode schemes. existence solutions and the stability closed-loop system established in continuous time. An implicit discretization approach proposed posedness Numerical simulations illustrate effectiveness discrete-time controller.

Abstract This article analyzes the high‐gain prediction approach for nonlinear input‐delay systems. The problem is discussed in light of weighted homogeneity and input‐to‐state stability. canonical form uniformly observable systems allows tuning linear‐part spectrum by multiplicity‐induced dominancy ensuring closed‐loop system stability using descriptor method Lyapunov–Krasovskii approach. Due to trade‐off between delay gain margin, limitation high that results time‐delay overcome a cascade...

In this paper we study the closed-loop dynamics of linear time-invariant systems with feedback control laws that are described by set-valued maximal monotone maps. The class considered in work is subject to both unknown exogenous disturbances and parameter uncertainty. It shown how design conventional sliding-mode controllers can be achieved using operators (which include but not limited signum function). Two cases analyzed: continuous-time discrete-time controllers. well-posedness together...

The use of multivalued controls derived from a special maximal monotone operator are studied in this note. Starting with strictly passive linear system (with possible parametric uncertainty and external disturbances) control law is derived, ensuring regulation the output to desired value. methodology used falls passivity-based context, where we study how affects dissipation equation closed-loop system, which derive its robustness properties. Finally, some numerical examples together...

Abstract We propose an observer for a susceptible‐infectious‐recovered epidemic model. The is then uplifted into predictor to compensate time delays in the input and output. Tuning criteria are given tuning gains of predictor, while estimation‐error stability ensured using Lyapunov‐Krasovskii functionals. predictor's performance first evaluated combination with time‐optimal control. It shown that nearly recovers level delay‐free system. Finally, real data from covid epidemic.

It is well known that if the linear time invariant system x = Ax + Bu, y Cx passive associated incremental x~ Ax˜ Bũ, Cx˜, with (~ (.) - (.)*, u* , y* constant input and output to an equilibrium state x*, also passive. In this paper, we identify a class of nonlinear systems form f(x) gu, h(x) whose model Using result then prove general RLC circuits convex proper electric magnetic energy functions resistors monotonic characteristic are globally stabilizable PI control.

This paper presents a nonsmooth adaptive extremum seeker that minimizes the hydrogen consumption in fuel-cell system. The operates by estimating gradient of objective function but, unlike other seekers, it does not require dither signal to produce such estimate. absence simplifies choice parameter values for seeker, and more importantly, allows converge optimal value exactly, only small neighborhood. proper functioning proposed scheme is proved using Lyapunov analysis. strategy tested on...