DIIES

In this paper the problem of detecting and isolating sensor faults on a certain class of nonlinear systems is considered. A procedure to design a bank of extended H∞H∞ observers for sensor fault detection and isolation (FDI) is carried out: each observer is composed of an open loop nonlinear part replicating the system dynamics and a linear feedback action. Sufficient conditions for the synthesis of the feedback action are provided in terms of linear matrix inequality (LMI) feasibility problems. Constraints on the position of the observer poles are added to fasten the residual generation dynamics and to avoid low-damped and/or high-frequency modes. Numerical results on the longitudinal dynamics of a commercial aircraft are provided to show the practical applicability of the proposed technique.

In this paper an innovative Radio Resource Management (RRM) algorithm is proposed with the purpose of increasing High Speed Packet Access (HSPA) performances, in terms of system capacity and service quality, when the Multimedia Broadcast Multicast Services (MBMS) is supplied. The proposed RRM algorithm exploits channel quality indications to set up point-to-multipoint connections to subgroups of multicast users and to select the proper modulation and coding schemes on the downlink. The number of subgroups is determined through an optimization technique that also takes into account the user satisfaction. An exhaustive simulation campaign is conducted to compare the proposed algorithm with the most promising approaches in the literature. Comparisons aim to assess the capability of the proposed RRM algorithm to efficiently manage group oriented services by providing an increment in terms of user satisfaction.

This study describes the application of the task priority null-space behavioural technique to the coordinated control of a team of flying vehicles with hovering capabilities, such as helicopters or quadrotors, in the presence of obstacles and no-fly zones. Once a flight mission is assigned to the team in terms of a target region to reach, each flying vehicle is required to accomplish four tasks with assigned priorities. Formation flight and collisions avoidance with other vehicles and unknown or moving obstacles tasks are formulated via analytical expressions as required by the classical null-space behavioural approach. Move to target and a priori known obstacle avoidance behaviours are obtained by solving a partial differential equation problem within the flight domain. The effectiveness of the proposed technique is discussed with regards to two-dimensional and three-dimensional numerical examples.

In this paper the implementation of an Output Feedback Receding Horizon Control (RHC) algorithm for constrained uncertain discrete-time linear systems subject to norm-bounded Linear Fractional Representation (LFR) model uncertainties has been developed. Performance and effective- ness of the proposed strategy have been numerically tested by considering the control augmentation problem of an High Al- titude Performance Demonstrator (HAPD) unmanned aircraft with redundant control surfaces.