Information and operational technologies merge into the so-called industrial Internet of Things, which is one of the basic pillars of the Industry 4.0 paradigm. Roughly speaking, yet-to-come services ...will be offered in the automation scenario by industrial devices having an internet connection for sharing data in the cloud. Currently, most efforts are in the development of protocols able to ensure horizontal interoperability among heterogeneous applications. Consequently, poor attention is devoted to time-related performance. In this paper, a new, full software, platform-independent approach is proposed for experimentally evaluating the delay in transferring information across local and intercontinental routes by applications leveraging on messaging middleware. The application is realized using the node-RED web-based framework, due to its availability on different platforms; the widely accepted message queue telemetry transport protocol has been chosen thanks to its low overhead and complexity. For sake of completeness, five different, private and public, brokers are used. The adopted industrial-grade hardware, complemented by global positioning system time reference, permits an overall synchronization and timestamping accuracy of a few milliseconds. The vast measurement campaign highlighted that, generally, quality of service (QoS) type 1 offers low end-to-end delay (average value less than 0.5 s) with reduced variability (0.1 s). However, the maximum end-to-end one-way delay ranges from 1 s for QoS 0 to less than 1.5 s for fully acknowledged QoS 2.
The control of industrial processes is an important theme covered by electrical engineering courses. The implementation of practical activities in laboratories with physical systems and devices ...complements the theory about control and automation addressed in lectures and enables apprentices to face real situations and problems present in industrial environments. This paper discusses the use of a didactic pilot plant by the students of University of São Paulo in an electrical engineering undergraduate discipline based on the project-based learning approach. The students performed simultaneous experiments with the following control systems: water temperature in the plant, water level in two reservoirs, and water flow rate through the plant, and also monitored the variables of the processes through a supervisory system. The answers of a questionnaire applied to the students after each project and the results registered in technical reports illustrate their performance in the discipline and provide a positive feedback on the use of the industrial plant as a didactic tool.
This paper proposes the development of an artificial neural network multilayer perceptron, implemented in a Foundation Fieldbus environment, to calculate the flow rate of natural gas by using an ...orifice plate in a closed pipe. The principal benefit of using neural networks lies in their low computational cost and simplicity of implementation, which allows just standard blocks to be used, making the technology independent of the Foundation Fieldbus system manufacturer. To perform the calculation, the proposed methodology relies on static pressure, temperature and differential pressure measurements, which are typically available in industrial plants. The developed methodology generates highly accurate results, and this approach can be implemented at a relatively low cost for Foundation Fieldbus system users.
•I would like to thank the reviewers for their comments to improve my paper. I have reviewed it and tried to follow the recommendations.•I have shortened the introduction and taken Refs. 14,15 off. In addition, I complemented the conclusion.•Please, find the answers for your questions in blue inside the document named “Letter_for_reviewers” I have attached to EES website.
The draft document of the new IEEE 802.15.4e specification assumes receiver initiated transmission (RIT) to reduce energy consumption of wireless sensors by turning off the radio periodically, even ...if they operate in mesh topology. The original contribution from this paper is developing and evaluating the RIT strategies intended for street lighting systems using wireless sensor networks to control and monitor public lighting systems. This paper presents a new configuration strategies for the RIT mechanism based on mapping weights assigned to devices when routing the gradient, which provides better performance when compared to the energy consumed by the network, average end-to-end delay and end-to-end delivery rate. The experiments were performed using the simulation tool ns-2. Results show that the developed strategies make the use of RIT in urban networks feasible, according to the requirements specified in RFC 5548.
Wireless sensor networks enable a variety of application scenarios due to their flexibility, the wide range of hardware solutions, as well as their simplicity. However, new challenges arise that make ...applications viable, such as power consumption, robust communication, limited storage and processing. One of the main elements among communication and power consumption optimization aspects is related to the protocol stack and especially the medium access layer, due to the nature of the wireless environment. Thus, this article proposes a multi-channel mechanism for asynchronous receiver-initiated MAC for low-power WSN. The proposed protocol reduces energy consumption due to message contention and idle listening through an initial recognition mechanism and an efficient multichannel mechanism based on knowledge of the best channel in each node of the network. For validation of the protocol, evaluations were made for consumption, latency and rate of delivery of the network in a web application, comparing the multichannel asynchronous protocol to the synchronous protocol. The results show that the synchronous protocol presents slight superiority in communication performance, whereas the asynchronous protocol presents lower consumption.
Public street lighting system consists of devices distributed in points of light and a supervision and control application. The system architecture is modular and expandable. In developing the work ...the C# language is adopted to develop the operation and monitoring via standard CyberOPC and XML file types are applied to the device description and definition of the network topology. This paper describes the validation proposed and the results obtained attests that this applied methodology is feasible and can be applied to other public lighting systems.
•Public street lighting system consists of points of light and a supervision.•The architecture of the proposed system is modular and expandable.•The system follows standard technologies.•The results obtained attests that this applied methodology is feasible.
This paper proposes RITMC, an asynchronous multichannel receiver-initiated MAC for low-power WSN. Through a comparison with already existing solutions, the RITMC tries to mitigate the message ...containment and the effect of Idle Listening through an initial recognition mechanism proposed by the A-MAC protocol, in addition to a multichannel mechanism and a more efficient diagnostic. In order to validate the proposed protocol, evaluations were made to the consumption of each node sensor, the network traffic for each link, the latency and the delivery rate of the network in a web application. The results show that the proposed RITMC minimizes energy consumption, besides improving communication and implementation when compared to the analyzed protocols.
The use of modern field devices in the automation industry has gained increased importance, since these devices offer a great opportunity to integrate self-diagnosis into an asset management ...environment. The need for asset management occurs during plant operation, where it is carried out by means of fine tuning, calibration, maintenance and changes of configuration to avoid undesired downtimes. Furthermore, in other areas of knowledge, specifically in mobile computing, many applications have been developed, but are still scarce when the subject is the solving of automation industry issues. This work is placed in the context of constructing an interface between these two worlds: mobile computing and industrial automation, in order to propose an integration architecture using a secure channel addressed by the CyberOPC to access an industrial plant from a mobile device aiming to perform activities related to asset management in Profibus PA networks. The proposed architecture was validated through simulations and real tests that resulted in an effective means of communicating with field devices allowing access to diagnostics and calibrations.
Display omitted
► Instable wireless communication nature. ► Appropriated routing protocol for urban networks. ► Acknowledgment mechanism based on selecting other neighbors’ nodes. ► Proposed protocol ...produces tolerated end-to-end delay values for this type of network.
This work is part of a research project that analyzes and develops efficient technologies for street lighting systems, and it describes a wireless sensor network system used for controlling and monitoring electrical variables. The street lighting system is composed by an urban network, where delivery rate (with priority related to other aspects), latency, energy efficiency, and fault tolerance are the non-functional requirements. Based on these requirements, this work presents a new network routing mechanism with acknowledgment, named GGPSR. The main purpose is to provide new means to reach high delivery rates in urban networks, with tolerated end-to-end delay values for this type of network. The mechanism consists of selecting nodes from neighbors others than the previously selected in order to find a path towards the destination. Simulation results demonstrate the algorithm fulfills the mentioned requirements.
Routing for wireless sensor networks based on gradient is a simple, reliable solution resulting in low information costs for the network package, as well as for the node itself. It is used for ...convergent traffic, where sensor nodes send messages to the sink node. Due to message transmission failures inherent to wireless sensor networks, researches in this area agree that point-to-point message confirmation in these networks is essential. This work proposes solutions for gradient-based routing using a confirmation mechanism for different neighbors, where four protocol variations are evaluated for sensor networks applications in order to monitor and control electrical variables. Results demonstrate that the protocol based on the longest distance has a satisfactory package delivery rate in severe conditions specified to the application. Furthermore, results show in which situations each routing protocol variation better suits the target application.
► Instable wireless communication nature. ► Appropriated routing protocol for urban networks andconvergent traffic. ► Acknowledgment mechanism based on selecting other neighbors’ nodes. ► Proposed protocol produces tolerated end-to-end delay values for this type of network.