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- Simulation optimization: a new job release approach for Industry 4.0Publication . Fernandes, Nuno O.; Thurer, Matthias; Pinho, Tatiana; Torres, Pedro; Silva, Sílvio do CarmoThe rise of Industry 4.0 has highlighted simulation optimisation as a decision-making tool for scheduling complex-manufacturing systems, specifically when resources are expensive and multiple jobs compete for the same resources. In this context, simulation optimisation provides an important mean to predict, evaluate and improve the short-term performance of the manufacturing system. An important scheduling function is controlled job release; jobs (or orders) are not released immediately to the shop floor, as they arrive to the production system, but release is controlled to stabilize work-in-process, reduce manufacturing lead times and meet customer delivery requirements. While there exists a broad literature on job release, reported release procedures typically use simple rules and greedy heuristics to determine which job to select for release. While this is justified by its simplicity, the advent of Industry 4.0 and its advanced scheduling techniques question its adequateness. In this study, an integer linear programming model is used to select jobs to be released to the shop floor. While there are some recent studies that use a similar procedure, these studies assume the release decision for a given set of jobs is optimized in discrete time intervals. In contrast, in this study, we analyse the impact of different triggering intervals. Experimental results for a pure flow shop support our contention that simulation optimisation as a decision-making tool for job release is likely to be too important to be overlooked
- Industrial IoT devices and cyber-physical production systems: review and use casePublication . Rubio, Eva Masero; Dionísio, Rogério Pais; Torres, PedroThe present paper describes the state of the art related to IIoT Devices and Cyber-Physical systems and presents a use case related to predictive maintenance. Industry 4.0 is the boost for smart manufacturing and demands flexibility and adaptability of all devices/machines in the shop floor. The machines must become smart and interact with other machines inside and outside the industries/factories. The predictive maintenance is a key topic in this industrial revolution. The reason is based on the idea that smart machines must be capable to automatically identify and predict possible faults and actuate before they occur. Vibrations can be problematic in electrical motors. For this reason, we address an experimental study associated with an automatic classification procedure, that runs in the smart devices to detect anomalies. The results corroborate the applicability and usefulness of this machine learning algorithm to predict vibration faults.
- Cyber-physical production systems supported by intelligent devices (smartboxes) for industrial processes digitalizationPublication . Torres, Pedro; Dionísio, Rogério; Malhão, Sérgio; Neto, Luis; Ferreira, Ricardo; Gouveia, Helena; Castro, Helderndustry 4.0 paradigm is a reality in the digitization of industrial processes and physical assets, as well as their integration into digital ecosystems with several suppliers of the value chain. In particular, Industry 4.0 is the technological evolution of embedded systems applied to Cyber-Physical Systems (CPSs). With this, a shift from the current paradigm of centralization to a more decentralized production, supported by Industrial Internet of Things (IIoT), is implied. The work reported in this paper focuses on the development of smart devices (SmartBoxes), based on low-cost hardware such as Raspberry Pi and also platforms certified for industrial applications, such as NI CompactRIO. Both platforms adopted the OPC-UA architecture to collect data from the shop-floor and convert it into OPC-UA Data Access standard for further integration in the proposed CPPS. Tests were also performed with the MQTT protocol for monitorization. Each SmartBox is capable of real-time applications that run on OPC-UA and MQTT, allowing easy interaction between supervisory systems and physical assets.
- Magnetoresistive sensors and piezoresistive accelerometers for vibration measurements: a comparative studyPublication . Dionísio, Rogério Pais; Torres, Pedro; Ramalho, Armando; Ferreira, Ricardohis experimental study focuses on the comparison between two different sensors for vibration signals: a magnetoresistive sensor and an accelerometer as a calibrated reference. The vibrations are collected from a variable speed inductor motor setup, coupled to a ball bearing load with adjustable misalignments. To evaluate the performance of the magnetoresistive sensor against the accelerometer, several vibration measurements are performed in three different axes: axial, horizontal and vertical. Vibration velocity measurements from both sensors were collected and analyzed based on spectral decomposition of the signals. The high cross-correlation coefficient between spectrum vibration signatures in all experimental measurements shows good agreement between the proposed magnetoresistive sensor and the reference accelerometer performances. The results demonstrate the potential of this type of innovative and non-contact approach to vibration data collection and a prospective use of magnetoresistive sensors for predictive maintenance models for inductive motors in Industry 4.0 applications.
- Desenvolvimento e teste de uma smartbox versátil para o chão de fábricaPublication . Torres, Pedro; Dionísio, Rogério PaisO surgimento de várias inovações tecnológicas permitiu a digitalização e a transformação da indústria, acompanhando o paradigma da Indústria 4.0. Tecnologias ligadas à robótica, aos sensores inteligentes, ao fabrico assistido por computador, à Internet das Coisas ou à Inteligência Artificial permitem a interligação entre os mundos físicos e virtuais. A interoperação entre todos estes domínios do saber é o princípio para transformar o processo de produção e criar uma fábrica inteligente. O foco deste artigo centra-se no desenvolvimento e teste de uma smartBox, capaz de comunicar eficientemente com os equipamentos no chão de fábrica e integrá-los em plataformas de IIOT (Industrial Internet of Things). À smartBox estão acopladas cartas e módulos de sensores e atuadores adequados às especificidades de cada máquina. esta tem de ser capaz de operar em tempo-real, ter uma boa performance e escalabilidade e bons canais de comunicação. O hardware da smartBox tem, por isso, de ser robusto, flexível, escalável, funcional, suportar diferentes tecnologias e permitir atualizações futuras, características essenciais a uma disseminação do conceito de Indústria 4.0 no chão de fábrica. Atualmente, existe no mercado uma diversidade de plataformas de hardware capazes de suportar o desenvolvimento da smartBox e servir de Gateway com qualquer equipamento no chão de fábrica. Por sua vez, os controladores lógicos programáveis e as suas plataformas de programação atuais são cada vez mais versáteis e intuitivos de programar, facilitando o processo de desenvolvimento, no sentido em que cada equipamento do chão de fábrica tem a sua especificidade, processo e tecnologia. Dado que muitas instalações industriais têm alguns anos de existência, por vezes as linhas de comunicação andam a par com as linhas de potência e é necessário prestar atenção às questões das interferências e formas de as minimizar. Nesse caso, os protocolos de comunicação a utilizar devem corresponder aos requisitos necessários em comunicações industriais, tal como a redundância, tolerância a interferências, reduzida latência, e minimizar as retransmissões e a perda de pacotes de dados. Nesse âmbito, apresentamos um caso de estudo em que é analisada a vibração de um motor elétrico; testamos duas soluções distintas para a smartBox: uma é baseada num sistema de aquisição de dados da National Instruments, onde o software LabVIEW é usado para adquirir, processar e armazenar os dados num servidor OPC (Object Linking and Embedding for Process Control). A outra solução incorpora as plataformas Arduino e EtherCAT. As características de ambas as propostas são analisadas e comparadas.
- Aplicação de técnicas de machine learning para classificação da aptidão dos solos para o regadioPublication . Geraldes, João; Marques, Sílvia Gouveia; Torres, Pedro; Duarte, A.C.Aplicação de técnicas de Machine Learning para classificação da aptidão dos solos para o regadio.
- Workload control and optimised order release: an assessment by simulationPublication . Fernandes, Nuno O.; Thürer, Matthias; Pinho, Tatiana; Torres, Pedro; Silva, Sílvio do CarmoAn important scheduling function of manufacturing systems is controlled order release. While there exists a broad literature on order release, reported release procedures typically use simple sequencing rules and greedy heuristics to determine which jobs to select for release. While this is appealing due to its simplicity, its adequateness has recently been questioned. In response, this study uses an integer linear programming model to select orders for release to the shop floor. Using simulation, we show that optimisation has the potential to improve performance compared to ‘classical’ release based on pool sequencing rules. However, in order to also outperform more powerful pool sequencing rules, load balancing and timing must be considered at release. Existing optimisation-based release methods emphasise load balancing in periods when jobs are on time. In line with recent advances in Workload Control theory, we show that a better percentage tardy performance can be achieved by only emphasising load balancing when many jobs are urgent. However, counterintuitively, emphasising urgency in underload periods leads to higher mean tardiness. Compared to previous literature we further highlight that continuous optimisation-based release outperforms periodic optimisation-based release. This has important implications on how optimised-based release should be designed.
- Robotic system navigation developed for hip resurfacing prosthesis surgeryPublication . Torres, Pedro; Gonçalves, Paulo; Martins, Jorge M.M.This paper discusses the design of a navigation system developed to assist surgeons in the procedures of Hip Resurfacing prosthesis surgeries. In conventional surgery, mechanical jigs are used to obtain a correct alignment for the metal prosthesis, however it is a very time consuming process. In order to solve this problem emerges a new robotic system, named HipRob. The system is composed by a pre-operative sub-system for planning the prosthesis correct alignment and a flexible robot to be co-manipulated by the surgeon during the drilling procedures on the femur head. The real-time navigation of this robotic system is based on the registration between the femur model, constructed from the CT scan, and the surface constructed with ultrasound images, acquired during the surgical procedures. Experimental results, performed in a femur phantom, show that the robot location errors are around 2 mm.
- O projeto INOVC+ no Instituto Politécnico de Castelo BrancoPublication . Rigueiro, Constança; Sampaio, Carlos; Farinha, Luís; Torres, PedroO Inov C+: Ecossistema de Inovação Inteligente da Região Centro é um programa estratégico especial de criação de novos produtos e serviços resultantes de I&D+I. É um programa de valorização de conhecimento científico e tecnológico que consiste na implementação de um inúmero de iniciativas para a criação de um sistema articulado entre a ciência e a tecnologia e as empresas para a Região Centro. Este projeto pretende contribuir para a afirmação da região centro como uma referência nacional de projeção internacional. Incorporar uma oferta completa de recursos, infraestruturas e atividades contribuindo para o desenvolvimento sustentável e da competitividade da Região Centro. O INOVC+ está a ser implementado na região centro, nomeadamente na região de Aveiro, Coimbra, Leiria, Viseu Dão e Lafões, Beira e Serra da Estrela, Beira Baixa, Oeste e médio Tejo. Com este projeto pretende-se maximizar o potencial de transferência de conhecimento das instituições de ensino, envolver as empresas e entidades não empresariais do sistema regional de I&I. Enfim, criar um networking que contribua para tornar o tecido empresarial mais inovador e as instituições de ensino superior mais empresariais. Nesta publicação pretende-se fazer um breve sumário do projeto e seus objetivos globais, bem como a apresentação, descrição dos trabalhos realizados e resultados alçados nas atividades principais no Instituto Politécnico de Castelo Branco.
- On the development of a component model for the realization of Industry 4.0Publication . Neto, Luís; Gonçalves, Gil; Torres, Pedro; Dionísio, Rogério PaisThe fourth industrial revolution promotes Industrial Cyber Physical Systems (ICPS) as the key to achieve smart, efficient, flexible and self-organizing production plants. In a shop floor there are heterogeneous physical and logical assets that form the ICPS. But without proper communication and composition techniques the integration of these assets in ICPS is compromised. Component Based Software Engineering (CBSE) is a discipline of growing relevance for ICPS because integration and composition issues have been extensively researched in the software domain. Under the Reference Architecture for Industry 4.0 (RAMI 4.0), the Industry 4.0 Component Model inherits aspects of CBSE to specify how several industrial plant assets can form an ICPS. The technological aspects for physical assets digitalization and integration have been explored, but the I4.0 Component model lacks proposals and use cases for dealing with industrial software components. In this work we discuss the development of the Smart Component Model as a proposal for integration of software components in ICPS. Furthermore, we focus on how prediction and monitoring applications could be converted in I4.0 Components and integrated in ICPS. To sustain our proposals, we describe a real industrial case study where these developments are being applied.