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In fast nonlinear model predictive control the sensitivitycomputation is one of the key aspects to reducecomputational burden, in fact specific automated andefficient procedures for that have been developed. Howeverthe number of sensitivity computations required toadequately approximate the nonlinear dynamics is typicallyhigh and fixed a priori. In this paper, we developa sensitivity updating scheme capable of reducing thenumber of sensitivity computations exploiting an onlinecurvature-based measure of nonlinearity of the system.The proposed strategy is applied to the sequentialquadratic programming framework with specific attentionto the Real-Time Iteration implementation. Simulationson the inverted pendulum benchmark show asignificant reduction of the number of the sensitivity updates,hence a reduction of the overall computationaltime.

IEEE 802.11 systems are drawing an ever increasing interest for wireless industrial communication, also thanks to the interesting features provided by the most recent and advanced amendments to this standard, such as IEEE 802.11n. Due to the intrinsic unreliability of the wireless medium, the current research efforts aim at improving both timeliness and reliability of such a protocol in view of its adoption for real-time applications. A significant issue in this context is represented by the reduction of the randomness that affects packet delivery times. An important benefit in this direction can be obtained by the deactivation of the standard legacy carrier sensing and backoff procedures. In this paper we show, through a simulative assessment, that a fine control of such features leads to improved real-time performance.

In the last years, IEEE 802.11 Wireless LANs (WLANs) have proved their effectiveness for a wide range of real-time industrial communication applications. Nonetheless, the enhancements at the PHY and MAC layers introduced by the IEEE 802.11n amendment have not yet been adequately addressed in the context of industrial communication. In this paper we investigate the impact of some IEEE 802.11n new features on some important performance figures for industrial applications, such as timeliness and reliability.

This paper investigates an original system for wireless control and monitoring of an agricultural machine. The system is implemented by means of an IEEE 802.11-based soft realtime communication architecture which enables the connection of the machine with off-the-shelf mobile devices, like widespread tablet PCs, that could hence replace traditional ad-hoc developed operator panels. The harsh surrounding environment, however, introduces severe requirements. Hence, focusing on the wireless communication behavior, the paper yields a thorough performance analysis derived by extensive experimental campaigns. By investigating the outcomes of these measurement sessions, the paper assesses some causes of performance degradation, and provides viable and easy to implement solutions to improve the overall system behavior.