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In this paper a distributed clock synchronization algorithm is proposed. The algorithm requires gossip asynchronous communication between the nodes of the network, and because of its proportional-integral (PI) structure it is able to compensate both initial offsets and different clock speeds. Convergence of the algorithm is proved and analysed with respect to the controller parameter, while scalability issues are addressed by simulations.

The paper deals with a Model Predictive Control (MPC) algorithm applied to electrical drives. The main contribution is a comprehensive and detailed description of the controller design process that points out the most critical aspects and gives also some practical hints for implementation. As an example, the MPC is developed for a permanent magnet synchronous motor drive. Speed and current controllers are combined together, including all of the state variables of the system, instead of keeping the conventional cascade structure. This way the controller enforces both the current and the voltage limits. Both simulation and experimental results point out the validity ofthe design procedure and the potentials of the MPC in the electrical drives field.

In this paper we analyze the problem of estimating a function from different noisy data sets collected by spatially distributed sensors and subject to unknown temporal shifts. We propose a novel approach based on non-parametric Gaussian regression and reproducing kernel Hilbert space theory that exploit compact and accurate representations of function estimates. As a first result, suitable minimization of inner products in reproducing kernel Hilbert spaces is used to obtain a novel time delay estimation technique when attention is restricted only to two signals. Then, we derive both a centralized and a distributed estimator to simultaneously identify the unknown function and delays for a generic number of networked sensors subject to a restricted communication graph. Numerical simulations are used to test the effectiveness of the proposed approaches.

The employment of Real-Time Ethernet networks in factory automation systems is rapidly increasing and several commercial products, with different characteristics, are already available from various manufacturers. Most of these networks have been included in both the IEC 61158 and IEC 61784 International Standards that, in addition, define a set of Performance Indicators. In this paper we focus on two popular Real Time Ethernet networks, namely Ethernet POWERLINK and EtherCAT, and we evaluate their performance for a typically deployed factory automation configuration. Specifically, we compute the most relevant performance indicators introduced by IEC 61784 standard and two (purposely defined) additional ones, namely minimum cycle time and jitter, which are suitable for the two networks considered.