Francesco Alessandro Cuzzola

Brief An improved approach for constrained robust model predictive control

In this paper, we present a new technique to address constrained robust model predictive control. The main advantage of this new approach with respect to other well-known techniques is the reduced conservativeness. Specifically, the technique described in this paper can be applied to polytopic uncertain systems and is based on the use of several Lyapunov functions each one corresponding to a different vertex of the uncertaintys polytope.

An LMI approach to periodic discrete-time unbiased filtering

The problem of unbiased filtering for a discrete-time linear periodic system is faced by means of linear matrix inequality techniques. As leading case, we derive the synthesis conditions to obtain an unbiased filter and an unbiased fixed-lag smoother enforcing a bound on the H∞ performance on the error dynamics.

An LMI approach for H ∞ analysis and control of discrete-time piecewise affine systems

In this paper we investigate some analysis and control problems for discrete-time hybrid systems in the piece-wise affine form. By using arguments from the dissipativity theory for non-linear systems, we show that H X analysis and synthesis problems can be formulated and solved via linear matrix inequalities by taking into account the switching structure of the considered system. In this paper we address the generalized problem of controlling hybrid systems whose switching structure does not depend only on the state but also on the control input.

Analysis and control with performance of piecewise affine and hybrid systems

In this paper we investigate some analysis and control problems with performance for discrete-time hybrid systems in the piecewise affine form. By using arguments from the dissipativity theory for nonlinear systems, we show that H/sub /spl infin// analysis and synthesis problems can be formulated and solved via linear matrix inequalities that take into account the switching structure of the systems. Moreover, such procedures can be generalized in order to solve both robust control problems and analysis/synthesis with other performance indices like the generalized H/sub 2/ norm.

Compensation of nonlinearities in a current transformer for the reconstruction of the primary current

The measurement of the current in industrial electrical devices is often carried out by current transformers. The reliability of these devices is compromised when the measured current is higher than the nominal value, due to the saturation and hysteresis effects of the magnetic core. In this paper, a nonlinear model of the current transformer is identified by means of a separable least squares technique. This model is successfully employed for the estimation of the primary current starting from experimental measurements of the distorted secondary current. In this way, a fair estimate of the primary current is obtained even when its maximum intensity reaches up to 60 times (or more) its nominal value. Some sensible experimental trials are reported in order to demonstrate the effectiveness of the technique developed.

Periodic active control of vibrations in helicopters: a gain-scheduled multi-objective approach

Abstract In this paper the problem of active control of vibrations in helicopters is faced for the generic flight condition by means of gain scheduling of periodic controllers. The problem can be reformulated as the one of rejecting a periodic disturbance having known frequency acting on the output of a suitable linear time-varying dynamic model. The problem has been translated into a linear matrix inequality formulation both in order to alleviate the computational aspects and to impose a tight limit on the effort of the control variable.

Continuous-time Periodic H∞ Filtering via LMI

In this paper, the problem of estimating the state and the input of a periodic continuous-time system by means of Linear Matrix Inequality (LMI) techniques is dealt with. Two approaches are considered: the first one is applicable only to stable periodic systems, whereas the second one, more conservative but also more flexible and computationally lighter, does not suffer from the same limits.

Lagrange stability and performance analysis of discrete-time piecewise affine systems with logic states

In this paper we consider discrete-time piecewise affine systems with boolean inputs, outputs and states and show that they can be represented in a logic canonical form where the logic variables influence the switching between different submodels but not the continuous-valued dynamics. We exploit this representation for studying Lagrange stability and developing performance analysis procedures based on linear matrix inequalities. Moreover, by using arguments from dissipativity theory for non-linear systems, we generalize our approach to solve the H ∞ analysis problem.

Generalized Active Control of Vibrations in Helicopters

The problem of active control of vibrations in the main rotor of helicopters is dealt with in the individual blade control framework. We propose a controller valid for a generic e ight condition by resorting to a linear parametrically varying (LPV)controltechniquecoupled with theso-called internalmodelcontrol (IMC)principle. The problem can be reformulated as the one of rejecting a periodic disturbance having known frequency acting on the output of a suitable linear time-varying dynamic model. The main advantage of our control technique is the e exibility of the LPV ‐IMC approach: It not only can be used with the generic e ight condition, but it also can be adapted to comply with a rotor blade model having a complex structure. We obtain a unique controller that automatically gets adapted to the measured advance ratio. An alternative to this control rationale would be to resort to the gain scheduling of periodic controllers, one for each forward e ight condition. However, as indicated by our previous research, this would require keeping memory of a large number of control laws in the onboard computer. Furthermore, an H1 control strategy is considered to take into account the effects of both unmodeled dynamics and unmodeled disturbances.

Cut Scheduling Optimization in Plate Mill Finishing Area Through Mixed-Integer Linear Programming

The recent development of steel technologies for plate production introduced new control and optimization issues that modern automation systems need to take into account. In this paper, the integration in an automation system of mixed-integer linear programming, which now relies on extremely efficient algorithms, and the use of new sensors for automatic detection of defects for the optimization of production and quality are presented here.