Antonio Pistorio

Sentinella: Smart Monitoring of Photovoltaic Systems at Panel Level

The monitoring of photovoltaic (PV) systems is important for the optimization of their efficiency. In this paper, a low-cost smart multisensor architecture equipped with voltage, current, irradiance, temperature, and inertial sensors, for the monitoring (at the panel level) of a PV system, is presented with the aim of detecting the causes of efficiency losses. The system is based on a Wireless Sensor Networks with sensing nodes installed on each PV panel. The acquired data are then transferred to a service center where dedicated paradigms continuously perform the assessment of electrical efficiency as well the estimation of correlated causes, at the single panel level. In this paper, the detection of critical faults (temporary and permanent shadowing, dirtying, and anomalous aging) is addressed. The methodology adopted to estimate efficiency losses and related causes is based on the comparison between the measured efficiency of each PV panel and the nominal one estimated in the real operating conditions. Moreover, the anomalous aging estimation is based on the five parameter model approach that exploits a dedicated minimization paradigm to analyze the mismatch between the nominal current-voltage model of the PV panel and the measured one. The main advantage of the proposed approach is the continuous monitoring of PV plants and the assessment of possible causes of power inefficiency at the PV panel level, allowing for the implementation of a really efficient distributed fault diagnosis system. The experimental results are presented along with the analysis of the uncertainty affecting the measurement system.

Multidisciplinary investigation on a lava fountain preceding a flank eruption: The 10 May 2008 Etna case

A multidisciplinary approach integrating a wide data set ranging from bulk rock compositions of the erupted products to volcanic tremor, long-period events, and tilt and gravity signals is used to investigate the source depth and magma dynamics of the 10 May 2008 lava fountain at Southeast crater (SEC) of Mount Etna. The investigation was undertaken in the framework of the previous 2007 explosive activity as well as the subsequent effusive eruption beginning 13 May 2008 and lasting up to July 2009. All the data concur in indicating that the 10 May lava fountain was generated by the fragmentation of a foam layer trapped at the top of a shallow reservoir, about 1500–1700 m below the summit of SEC. The shift from the episodic strombolian/lava fountain activity occurring in 2007 at SEC to the more powerful 10 May 2008 lava fountain is explained by the intrusion of a new more primitive magma into the shallow reservoir. Data also indicate that an attempted magma intrusion east of the summit area occurred during the 10 May fire fountain. This event caused the fracturing and weakening of the surrounding rocks and created a preferential pathway for the penetration of the magma that, only 3 days later, started to feed the 2008–2009 effusive eruption.

A smart wireless sensor network for AAL

This paper deals with a novel system to assist weak people in exploring indoor environment. The system is based on a WSN and smart paradigms which extract a suitable information from data collected through the multi-sensor architecture. Such information is then provided to the user for a safe and efficient exploitation of the environment and to the supervisor for a suitable assessment and management of hazard situations.

RESIMA: A new WSN based paradigm to assist weak people in indoor environment

This paper deals with the RESIMA architecture developed to assist people in performing daily activity in indoor environment. As respect to solutions presented in the SOTA, RESIMA is a smart multi-parametric assistive system which performs a high resolution monitoring of the user position in the spatial-temporal domain as well as a deep inertial monitoring of the user status, thus assuring a reliable and continuous form of assistance to weak users. The system is based on a Wireless Sensor Network and smart paradigms which extract relevant information from data collected through the multi-sensor architecture. The paper mainly focuses on the multi-sensor system architecture and smart paradigms used to implement user localization. Positioning system accuracy of about 3 cm has been obtained while the system shows good reproducibility and reliability.

SENTINELLA: A WSN for a smart monitoring of PV systems at module level

Monitoring a PV plant has a remarkable impact on its efficiency. In this context, Wireless Sensor Networks (WSNs) can be a low cost, but reliable solution to perform the real-time monitoring task. The main objective of this work is the realization of a WSN that allows to monitor at panel level the efficiency of Photovoltaic (PV) panels, to provide data useful to investigate on causes of efficiency losses and to detect inertial events possibly related to attempts of theft or tampering but also to mechanical striking events. Nodes of the WSN, which are installed on each PV module, are equipped with voltage, current, irradiance, temperature and inertial sensors. Acquired data are then transferred to a management center which is in charge of estimating efficiency losses and correlated causes, tampering and inertial events at the level of the single module. In particular, this paper is focused on a solution for the automatic estimation of efficiency losses of a PV module and related causes.

A contactless inkjet printed passive touch sensor

A new planar contactless passive all-inkjet printed touch sensor realized by low cost printing technology on a PET substrate is discussed. The device exploits a capacitive readout strategy while the contactless operation is based on the LC resonance method which converts changes of C into the frequency domain. Advantages of the proposed solution reside both in the technological process and contactless readout. Main outcomes of the low cost inkjet technology adopted is the rapid prototyping of really cheap disposable sensors. The passive and contactless readout strategy enables the use of the touch sensor in applications where the device cannot coexist with power sources and conditioning/reading circuit such as uses in hazardous environments.

Low-Cost Inkjet Printing Technology for the Rapid Prototyping of Transducers

Recently, there has been an upsurge in efforts dedicated to developing low-cost flexible electronics by exploiting innovative materials and direct printing technologies. This interest is motivated by the need for low-cost mass-production, shapeable, and disposable devices, and the rapid prototyping of electronics and sensors. This review, following a short overview of main printing processes, reports examples of the development of flexible transducers through low-cost inkjet printing technology.

A Low-Cost Accelerometer Developed by Inkjet Printing Technology

In this paper, an inkjet-printed sensor in the mesoscale is presented with the aim to investigate its behavior as an accelerometer in the low-frequency domain (up to 20 Hz), which properly fits with the need of typical applications in the field of human and seismic monitoring. The accelerometer consists of a Polyethylene terephthalate membrane clamped by four spring legs to a fixed support. The sensing readout strategy is implemented through four strain gauges directly printed onto the flexible substrate. The advantages of the approach proposed are mainly related to the adopted low-cost direct printing technology, which allows for the realization of cheap and customizable devices. The sensor behavior has been deeply investigated. The device responsivity and resolution are 9.4 mV/g and 0.126 g, respectively, at 10 Hz, and 41.0 mV/g and 0.003 g, respectively, at 35 Hz. The performances obtained encourage the development of the all-inkjet-printed sensor proposed, especially taking into account its low cost and disposable features.

A low cost multi-sensor approach for early warning in structural monitoring of buildings and structures

Early warning systems (EWS) for the structural monitoring of buildings and structures have a notable impact for the safety of the same structures and of the populations. These systems have significantly increased with the availability of wireless sensor networks (WSNs) which represent a low cost, but a reliable solution, to perform the real-time monitoring task. The main goal of this work is the realization of a customized multi-sensor node, based on a WSN, suitable for the implementation of a distributed EWS for the structural monitoring of buildings and structures. The proposed solution uses two inclinometers and one triaxial accelerometer, a microcontroller platform and a ZigBee communication tool for data communications. To allow a context-adaptive architecture of the developed system, three operating mode have been defined: stand-alone, continuous data transfer, and mixed mode. The storage capability of acquired data was also implemented.

Investigation of a Nonlinear Energy Harvester

The use of nonlinear architectures for energy harvesting can significantly improve the efficiency of the conversion mechanism, as respect to the use of linear devices, especially when the mechanical energy is distributed over a wide frequency bandwidth. This is the case of energy harvesting form wideband vibrations. In this paper, performances of a piezoelectric energy harvester exploiting a snap-through buckling configuration are investigated. The device is supposed to switch between its stable states, where two piezoelectric transducers are positioned to implement the mechanical-to-electric conversion mechanism. A simple theoretical two-state model of the device is presented along with a complete experimental characterization aimed at investigating the mechanical and electrical behaviors of the device. The device is demonstrated to be capable of scavenging energy from vibration sources in the range 0.5–5 Hz, but could be exploited up to 15 Hz with an acceptable loss of efficiency. The bandwidth of the device is compatible with applications where the vibrations occur at low frequencies, e.g., in the case of a running human. In this paper, we demonstrate the viability of our setup for harvesting energy from mechanical vibrations. The device is seen to generate power up to