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Event-triggered transmission for linear control over communication channels Forni, Fulvio ; ; et al in Automatica (2014), 50(2), 490498 We consider an exponentially stable closed loop interconnection of a continuous linear plant and a continuous linear controller, and we study the problem of interconnecting the plant output to the ... [more ▼] We consider an exponentially stable closed loop interconnection of a continuous linear plant and a continuous linear controller, and we study the problem of interconnecting the plant output to the controller input through a digital channel. We propose a family of "transmission-lazy" sensors whose goal is to transmit the measured plant output information as little as possible while preserving closed-loop stability. In particular, we propose two transmission policies, providing conditions on the transmission parameters. These guarantee global asymptotic stability when the plant state is available or when an estimate of the state is available (provided by a classical continuous linear observer). Moreover, under a specific condition, they guarantee global exponential stability [less ▲] Detailed reference viewed: 23 (1 ULg)Model recovery anti-windup for continuous-time rate and magnitude saturated linear plants Forni, Fulvio ; ; in Automatica (2012), 48(8), 15021513 In this paper two approaches are given for anti-windup design for nonlinear control systems with linear plants subject to limitations both in the magnitude and the rate of variation of the control input ... [more ▼] In this paper two approaches are given for anti-windup design for nonlinear control systems with linear plants subject to limitations both in the magnitude and the rate of variation of the control input. Both approaches are based on the so-called Model Recovery Anti-windup (MRAW) framework. The ﬁrst approach is built by treating the rate+magnitude saturation as a single dynamic nonlinearity, while in the second one, the dynamic compensator dynamics is extended with extra states to treat the two saturations separately. Both approaches lead to global stability with exponentially stable plants and local stability in all other cases. For both approaches, stability and performance guarantees are proven, numerical recipes are given and the relative merits are comparatively highlighted on a simulation example. [less ▲] Detailed reference viewed: 73 (40 ULg)Lazy sensors for the scheduling of measurement samples transmission in linear closed loops over networks Forni, Fulvio ; ; et al in 49th IEEE Conference on Decision and Control (cdc 2010) (2010) We consider an exponentially stable close-loop interconnection of a continuous linear plant and a continuous linear controller, and we study the problem of interconnecting the plant output to the ... [more ▼] We consider an exponentially stable close-loop interconnection of a continuous linear plant and a continuous linear controller, and we study the problem of interconnecting the plant output to the controller input through a network. We propose a family of "lazy sensors" whose goal is to transmit the measured plant output information as little as possible while preserving closed-loop stability. In particular, we propose three transmission policies, providing conditions on the transmission parameters. These guarantee global asymptotic stability when the plant state is available, and global practical stability when the plant state is not available. Simulation results confirm the effectiveness of the proposed strategies. [less ▲] Detailed reference viewed: 22 (8 ULg)A Family of Global Stabilizers for Quasi-Optimal Control of Planar Linear Saturated Systems Forni, Fulvio ; ; in IEEE Transactions on Automatic Control (2010), 55(5), 1175-1180 We propose a family of nonlinear state feedback global stabilizers for all planar linear systems which are globally stabilizable by bounded inputs (namely, all non exponentially unstable linear systems ... [more ▼] We propose a family of nonlinear state feedback global stabilizers for all planar linear systems which are globally stabilizable by bounded inputs (namely, all non exponentially unstable linear systems). This family is parametrized by a nonlinear function whose selection can yield quasi time-optimal responses, where the "quasi" is required to achieve local exponential stability of the closed loop. The arising trajectories are quasi-time-optimal for arbitrarily large initial conditions; so, we expect the very simple proposed nonlinear control law to be very useful for embedded control applications with strong computational constraints. [less ▲] Detailed reference viewed: 32 (11 ULg)An almost Anti-Windup scheme for plants with magnitude, rate and curvature saturation Forni, Fulvio ; ; in American Control Conference (ACC 2010) (2010) We address the anti-windup augmentation problem for plants with saturations on the magnitude, rate and curvature of the control input. To this aim, given an unconstrained closed-loop, we generate a ... [more ▼] We address the anti-windup augmentation problem for plants with saturations on the magnitude, rate and curvature of the control input. To this aim, given an unconstrained closed-loop, we generate a slightly modified strictly proper controller for which the derivatives of the control signal are available and we solve the anti-windup problem for this modified control scheme (namely, an almost anti-windup for the original closed-loop). Based on this “almost” approach, we revisit an existing Model Recovery anti-windup solution for rate and magnitude saturated plants and then we extend the results to the case of rate, magnitude and curvature saturation, by providing a Model Recovery solution to this additional problem. An example illustrates the peculiarities and the effectiveness of the proposed solutions. [less ▲] Detailed reference viewed: 16 (0 ULg)Gain-scheduled, model-based anti-windup for LPV systems Forni, Fulvio ; in Automatica (2010), 46(1), 222-225 The aim of this paper is to show that a recently proposed technique for anti-windup control of exponentially unstable plants can be easily extended to solve the corresponding robust anti-windup problem ... [more ▼] The aim of this paper is to show that a recently proposed technique for anti-windup control of exponentially unstable plants can be easily extended to solve the corresponding robust anti-windup problem for linear parameter varying systems, for which the time varying parameters are measured online. The proposed technique is minimally conservative with respect to the size of the resulting operating region (which coincides, up to an arbitrarily small quantity, with the largest set on which asymptotic stability can be guaranteed for the considered plant with the given saturation level and uncertainty characteristics), and is not limited to plants having only small uncertainties or being open-loop stable. [less ▲] Detailed reference viewed: 54 (6 ULg)Model Recovery Anti-Windup for plants with rate and magnitude saturation Forni, Fulvio ; ; in European Control Conference (2009) (2009) In this paper two alternative approaches are provided to design an anti-windup compensator for control systems subject to limitations both in the magnitude and the rate of variation of the plant input ... [more ▼] In this paper two alternative approaches are provided to design an anti-windup compensator for control systems subject to limitations both in the magnitude and the rate of variation of the plant input. For both approaches, constructive numerical recipes are given and the relative merits are highlighted. [less ▲] Detailed reference viewed: 53 (8 ULg)Globally stabilizing quasi time-optimal control of planar saturated linear systems Forni, Fulvio ; ; in 16th Mediterranean Conference on Control and Automation (2008) (2008) Detailed reference viewed: 10 (3 ULg)Model based, gain-scheduled anti-windup control for LPV systems Forni, Fulvio ; in 46th IEEE Conference on Decision and Control (cdc 2007) (2007) In this paper we show that a recently proposed technique for anti-windup control of exponentially unstable plants can be easily extended to solve the corresponding robust anti-windup problem for linear ... [more ▼] In this paper we show that a recently proposed technique for anti-windup control of exponentially unstable plants can be easily extended to solve the corresponding robust anti-windup problem for linear parameter varying systems, for which the time varying parameters are measured online. For this class of plants, it is shown that the proposed technique is minimally conservative with respect to the size of the resulting operating region: in particular, such a region is (up to an arbitrarily small quantity) exactly the largest set on which asymptotic stability can be guaranteed for the considered plant, for the given saturation level and uncertainty characteristics. [less ▲] Detailed reference viewed: 26 (6 ULg) |
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