Cookies Policy
The website need some cookies and similar means to function. If you permit us, we will use those means to collect data on your visits for aggregated statistics to improve our service. Find out More
Accept Reject
  • Menu
Interest
Topics
Details

Details

Publications

2023

Radio Interference of Wireless Networks and the Impact of AR/VR Applications in Industrial Environments

Authors
Dionísio, R; Ribeiro, F; Metrôlho, J;

Publication
Electronics (Switzerland)

Abstract
The use of wireless communications systems on the factory shop floor is becoming an appealing solution with many advantages compared to cable-based solutions, including low cost, easy deployment, and flexibility. This, combined with the continuous growth of low-cost mobile devices, creates opportunities to develop innovative and powerful applications that, in many cases, rely on computing and memory-intensive algorithms and low-latency requirements. However, as the density of connected wireless devices increases, the spectral noise density rises, and, consequently, the radio interference between radio devices increase. In this paper, we discuss how the density of AR/VR mobile applications with high throughput and low latency affect industrial environments where other wireless devices use the same frequency channel. We also discuss how the growing number of these applications may have an impact on the radio interference of wireless networks. We present an agnostic methodology to assess the radio interferences between wireless communication systems on the factory floor by using appropriate radio and system models. Several interference scenarios are simulated between commonly used radio systems: Bluetooth, Wi-Fi, and WirelessHART, using SEAMCAT. For a 1% probability of interference and considering a criterion of C/I = 14 dB, the simulations on an 80 m × 80 m factory shop floor show that low-bandwidth systems, such as Bluetooth and WirelessHART, can coexist with high-bandwidth and low-latency AR/VR applications running on Wi-Fi mobile terminals if the number of 11 Wi-Fi access points and 80 mobile AR/VR devices transmitting simultaneously is not exceeded. © 2022 by the authors.

2022

Machinery Retrofiting for Industry 4.0

Authors
Torres, P; Dionisio, R; Malhao, S; Neto, L; Goncalves, G;

Publication
INNOVATIONS IN MECHATRONICS ENGINEERING

Abstract
The paper presents an approach for the retrofitting of industrial looms on the shop floor of a textile industry. This is a real case study, where there was a need to update the equipment, providing the machines with communication features aligned with the concept of Industry 4.0. The work was developed within the scope of the research project PRODUTECH-SIF: Solutions for the Industry of the Future. Temperature, Inductive, Acoustic and 3-axis Accelerometers sensors were installed in different parts of the machines for monitorization. Data acquisition and processing is done by a SmarBox developed on a cRIO 9040 from National Instruments. A SmartBox processes data from one to four looms, allowing these old machines to have communication capacity and to be monitored remotely through the factory plant's MES/ERP. Communication can be done through the OPC UA or MQTT architecture, both protocols aligned with the new trends for industrial communications. The sensor data will be used to feed production and manufacturing KPIs and for predictive maintenance. The approach presented in this paper allows industries with legacy equipment to renew and adapt to new market trends, improving productivity rates and reduced maintenance costs.

2022

Learning Environment Digital Transformation: Systematic Literature Review

Authors
Lolic, T; Stefanovic, D; Dionisio, R; Dakic, D; Havzi, S;

Publication
Proceedings on 18th International Conference on Industrial Systems – IS’20 - Lecture Notes on Multidisciplinary Industrial Engineering

Abstract

2022

A Review of Intelligent Sensor-Based Systems for Pressure Ulcer Prevention

Authors
Silva, A; Metrolho, J; Ribeiro, F; Fidalgo, F; Santos, O; Dionisio, R;

Publication
COMPUTERS

Abstract
Pressure ulcers are a critical issue not only for patients, decreasing their quality of life, but also for healthcare professionals, contributing to burnout from continuous monitoring, with a consequent increase in healthcare costs. Due to the relevance of this problem, many hardware and software approaches have been proposed to ameliorate some aspects of pressure ulcer prevention and monitoring. In this article, we focus on reviewing solutions that use sensor-based data, possibly in combination with other intrinsic or extrinsic information, processed by some form of intelligent algorithm, to provide healthcare professionals with knowledge that improves the decision-making process when dealing with a patient at risk of developing pressure ulcers. We used a systematic approach to select 21 studies that were thoroughly reviewed and summarized, considering which sensors and algorithms were used, the most relevant data features, the recommendations provided, and the results obtained after deployment. This review allowed us not only to describe the state of the art regarding the previous items, but also to identify the three main stages where intelligent algorithms can bring meaningful improvement to pressure ulcer prevention and mitigation. Finally, as a result of this review and following discussion, we drew guidelines for a general architecture of an intelligent pressure ulcer prevention system.

2022

Bragg Grating Tuning Techniques for Interferometry Applications

Authors
Dionísio, R;

Publication
Optical Interferometry - A Multidisciplinary Technique in Science and Engineering

Abstract
Fiber Bragg grating is widely used in optical fiber applications as a filter or a sensor due to its compact size and high sensitivity to physical conditions, such as temperature and strain. The purpose of this chapter is to describe the implementation and characterization of two tuning methods for optical fiber Bragg gratings, varying the temperature or the length of the fiber. Among the methods using mechanical deformation, compression of the fiber by bending a flexible sheet aggregated with the Bragg grating has shown very interesting tuning results, reaching 19.0 nm with minimum reflection bandwidth variation over the entire tuning range. Stretching the fiber has presented several drawbacks, including breaking of the fiber and a lower tuning range of 4.9 nm. Temperature tuning technique presents good linearity between tuning range and temperature variation but at the cost of a low tuning range (0.4 nm) and a permanent high current electrical source.