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The explicit reference governor is a constrained control scheme that was originally introduced for generic nonlinear systems. This paper presents two explicit reference governor strategies that are specifically tailored for the constrained control of linear time-invariant systems subject to linear constraints. Both strategies are based on the idea of maintaining the system states within an invariant set which is entirely contained in the constraints. This invariant set can be constructed by exploiting either the Lyapunov inequality or modal decomposition. To improve the performance, we show that the two strategies can be combined by choosing at each time instant the least restrictive set. Numerical simulations illustrate that the proposed scheme achieves performances that are comparable to optimisation-based reference governors. [ABSTRACT FROM AUTHOR]

• Reformulation of a physiologically-based model describing ectotherms. • Spatialization of a system of ordinary differential equations describing life stages. • Mathematical description of three typical case studies of ecological interest. • Analysis of the model behavior. • Simulations in the case study of Drosophila suzukii. The mathematical description of the dynamics of ectotherm populations has a crucial role in understanding and forecasting insect pests outbreaks, as well as to support the formulation of low-impact control strategies. Even though in recent years a considerable step forward has been made in modelling the biological life cycle of many ectotherms, the modelling of spatial aspects still remain partially unexplored. This work aims to fill a gap in knowledge by modelling the environmental factors-driven spatial motion of insects considering populations which develop over time, and through their life stages. Accordingly, spatial motion is proposed by modifying an existing physiologically based model by adding a subdivision of the area of interest in interconnected subareas represented by means of graph. Besides the mathematical framework, the model behavior is theoretically analyzed by considering three common cases of spatial motion occurring in cultivated fields: trap attraction, wind transportation, and a combination of the both cases. Simulations focus on the case of Drosophila suzukii , chosen due to the large amount of biological data available in the current literature. The behavior analysis shows the great potential of the model presented in this paper in the field of pest management, agriculture, and ecology. [ABSTRACT FROM AUTHOR]

Abstract: This paper proposes a novel class of Command Governor (CG) strategies for input and state-related constrained discrete-time LTI systems subject to bounded disturbances in the absence of explicit state or output measurements. While in traditional CG schemes the set-point manipulation is undertaken on the basis of either the actual measure of the state or its suitable estimation, it is shown here that the CG design problem can be solved, with limited performance degradation and with similar properties, also in the case that such an explicit measure is not available. This approach, which will be referred to as the Feed-Forward CG (FF-CG) approach, may be a convenient alternative CG solution in all situations whereby the cost of measuring the state may be a severe limitation, e.g. in distributed or decentralized applications. In order to evaluate the method proposed here, numerical simulations on a physical example have been undertaken and comparisons with the standard state-based CG solution reported. [Copyright &y& Elsevier]

Abstract This paper addresses the tracking problem of constant references for multiple-input multiple-output linear time-invariant systems. We provide necessary and sufficient conditions for the solvability of the problem under the minimal set of assumptions that guarantee the well-posedness of every control problem requiring stability. Our approach allows to solve tracking problems for systems which are possibly nonright-invertible, simply (not asymptotically) stabilizable, and possibly with invariant zeros at the origin. Our methodology is constructive and results in the design of a stabilizing feedback matrix and a feedforward signal which solve the problem. Graphical abstract [ABSTRACT FROM AUTHOR]

Abstract: This paper proposes a fast ellipsoidal Model Predictive Control (MPC) strategy to address feedback regulation problems for constrained polytopic Linear Parameter Varying (LPV) systems subject to bounded disturbances. In order to deal with the specific non-convex structure of the state prediction tubes arising in LPV contexts, a new convexification procedure is proposed and, based on the off-line computation of a sequence of inner ellipsoidal approximations of exact one-step controllable sets, a computationally low-demanding MPC algorithm is presented. Comparisons with state-of-the-art MPC control algorithms for LPV systems are reported in a final numerical example where several methods are contrasted in terms of achievable domains of attraction, control performance, numerical burdens and memory requirements. [Copyright &y& Elsevier]