The Industry 4.0 has led to a significant transformation in manufacturing and industrial processes, characterized by increased connectivity and widespread digitalization. This revolution is driven by the convergence of IT (Information Technology) paradigms with OT (Operational Technology) domains. Virtualization technology plays a crucial role in this integration, thanks to its characteristics of agility, scalability, and efficiency. This work investigates the virtualization of Programmable Logic Controllers (PLCs) and it is focused on the need for evaluating their performance. PLCs are essential components of industrial automation and are being virtualized to increase flexibility, reduce hardware dependencies, and enable seamless integration with IT infrastructures. This work proposes a methodology for evaluating the execution time of a benchmark program and the PLC real-time behavior. Experiments on a real use case demonstrate that the PLCs implemented in containers may be 50 times faster than the real ones in executing data elaboration, while no significant differences were observed in real-time communication. In any case, virtual PLCs are characterized by greater jitter with respect to real PLCs.

The demand for enhanced flexibility in automation systems, dictated by initiatives as the Industry 4.0 in Europe or the Industrial Internet Consortium in the United States, can be satisfied inheriting solutions of the information technology (the so called IT-OT convergence). Other than communication and cloud technologies, virtualization will play a relevant role in the next future. The use of lightweight virtualization, e.g., in the form of containers for implementing the edge computing paradigm, is a promising tool to dynamically provide services depending on the actual production needs. However, requirements of industrial automation applications are different from those of office-like counterparts. For this reason, methodologies for evaluating obtainable performance are needed. In this work, an industrial-grade framework, the Siemens Industrial Edge, is considered. A reference testbed is setup to evaluate latencies when information is exchanged between two user applications. Experiments demonstrate that round trip time in the order of 10 ms is feasible, compatible with the requirements of both process control systems and supervision applications.

LPWAN, an acronym for Low Power Wide Area Network, addresses all the wireless communication solutions aiming at maximize the lifetime of battery powered end devices by means of high-sensitivity radios and sporadic data transactions. Among the different members of the LPWAN family, LoRaWAN is an emerging solution satisfying requirements of many Internet of Things (IoT) related applications. LoRa WAN supports both public and private deployments, operating in unlicensed frequency bands. Handling critical messages, e.g., originated after emergency events in industrial plants, is out of the original LoRaWAN scope. For this reason, the LoRa-REP replication scheme was proposed to increase reliability and to reduce latency of confirmation. In this work, obtainable performance are further improved allowing frame overlaps in time and frequency, exploiting LoRa virtual channels. In particular, Software Defined Radio paradigm is exploited for implementing a proof-of-concept to be used in real-world trials. The preliminary results, supported by simulations as well, are discusses, confirming the feasibility and effectiveness of the proposed approach.

Low Power Wide Area Networks (LPWANs) are wireless technologies well accepted in the Internet of Things (IoT) scenarios because they operate in both public and private infrastructure using unlicensed frequency bands. Differently from other wireless standards, the LPWAN target applications are low-rate, sporadic-transmission, low-energy systems. Surely, fast response time and high reliable communication are out of the original LPWAN scope. In this work, a first investigation about the use LoRaWAN (one the most diffused LPWAN protocols) for notification of emergency messages across industrial plants is reported. The opportunity of using recently proposed low-cost repeaters, and the creation of a clever replication pattern of radio messages are the keys of the proposed approach. The results of the preliminary analytical feasibility assessment are presented, confirming the possibility to increase success ratio of notification and respective confirmation in case of emergencies.

The LoRaWAN technology, an example of low power wide area network, is considered a possible IoT-derived solution for realizing private cellular (single-hop) communications in the industrial domain. However, despite LoRaWAN promises long range and dense environments with many obstacles (as the industrial ones), it may suffer from coverage issue. Additionally, the inverse relationship between data rates and range may be unacceptable for many industrial applications. In this article, an innovative LoRaWAN range extender (based on an enhanced LoRaWAN node) is described, and its integration in the infrastructure of industrial Internet of Things (IIoT)-enabled industrial wireless networks is presented. A frame relay strategy is suggested, thus avoiding to tradeoff the highest data rates against an increased sensitivity. The feasibility of the solution is formally verified and the features of the realized proof-of-concept prototype, based on commercially available hardware, are discussed. The experimental results, obtained with a purposely designed test bench, show the effectiveness of the proposed approach. In particular, the range extender is transparent for legacy LoRaWAN networks as confirmed by correct relaying of uplink and downlink for different types of LoRaWAN message.

In this paper a novel and simple CMOS integrated interface is presented. The circuit is suitable for typical gas sensor applications being able to reveal: a) high resistive values over a wide-range (more than five orders of magnitude, ranging from hundreds of kilohm up to tens of gigohm); b) relatively low value capacitances (few picofarad) and their variations. The proposed front-end utilizes, as active blocks, operational amplifiers that have been implemented, at transistor level, as suitable OTA showing low input voltage offset and relatively high slew-rate characteristics. With respect to the most topologies in the literature, the proposed interface, based on an oscillating architecture, is very simple and allows to obtain good performances all over a high dynamic range without any initial calibration. System sensitivity has been set to 0.1 ms/MOmega. Experimental measurements, performed on chip, fabricated in a standard and low-cost CMOS technology (AMS 0.35 mum), have shown a good linearity confirming the front-end validity in a large frequency range.