Using a mobile robot for hazardous substances detection in a factory environment

Dupla diplomação com a UTFPR - Universidade Tecnológica Federal do ParanáIndustries that work with toxic materials need extensive security protocols to avoid accidents. Instead of having fixed sensors, the concept of assembling the sensors on a mobile robot that performs the scanning through a defined path is cheaper, configurable and adaptable. This work describes a mobile robot, equipped with several gas sensors and LIDAR, that follows a trajectory based on waypoints, simulating a working Autonomous Guided Vehicle (AGV). At the same time, the robot keeps measuring for toxic gases. In other words, the robot follows the trajectory while the gas concentration is under a defined value. Otherwise, it starts the autonomous leakage search based on a search algorithm that allows to find the leakage position avoiding obstacles in real time. The proposed methodology is verified in simulation based on a model of the real robot. Therefore, three path plannings were developed and their performance compared. A Light Detection And Ranging (LIDAR) device was integrated with the path planning to propose an obstacle avoidance system with a dilation technique to enlarge the obstacles, thus, considering the robot’s dimensions. Moreover, if needed, the robot can be remotely operated with visual feedback. In addition, a controller was made for the robot. Gas sensors were embedded in the robot with Finite Impulse Response (FIR) filter to process the data. A low cost AGV was developed to compete in Festival Nacional de Robótica (Portuguese Robotics Open) 2019 - Gondomar, describing the robot’s control and software solution to the competition.As indústrias que trabalham com materiais tóxicos necessitam de extensos protocolos de segurança para evitar acidentes. Ao invés de ter sensores estáticos, o conceito de instalar sensores em um robô móvel que inspeciona através de um caminho definido é mais barato, configurável e adaptável. O presente trabalho descreve um robô móvel, equipado com vários sensores de gás e LIDAR, que percorre uma trajetória baseada em pontos de controle, simulando um AGV em trabalho. Em simultâneo são efetuadas medidas de gases tóxicos. Em outras palavras, o robô segue uma trajetória enquanto a concentração de gás está abaixo de um valor definido. Caso contrário, inicia uma busca autônoma de vazamento de gás com um algoritmo de busca que permite achar a posição do gás evitando os obstáculos em tempo real. A metodologia proposta é verificada em simulação. Três algoritmos de planejamento de caminho foram desenvolvidos e suas performances comparadas. Um LIDAR foi integrado com o planejamento de caminho para propôr um sistema de evitar obstáculos. Além disso, o robô pode ser operado remotamente com auxílio visual. Foi feito um controlador para o robô. Sensores de gás foram embarcados no robô com um filtro de resposta ao impulso finita para processar as informações. Um veículo guiado automático de baixo custo foi desenvolvido para competir no Festival Nacional de Robótica 2019 - Gondomar. O controle do veículo foi descrito com o programa de solução para a competição

Obtenção de óxidos mistos SiO2-ZrO2 por método sol-gel e avaliação da sua atividade catalítica na reação de transesterificação do óleo de soja

O biodiesel é o segundo biocombustível mais consumido no mundo. Atualmente ele é obtido a partir dos óleos de palma, soja e canola que representam quase 90% do custo de produção. Visando reduzir este custo, novos catalisadores têm sido projetados para serem empregados em processos com matérias-primas mais baratas, ricas em ácidos graxos livres. Óxidos mistos à base de ZrO2 são catalisadores conhecidos e podem apresentar características promissoras para a catálise ácida do biodiesel. Além disso, por se tratar de um catalisador heterogêneo, este óxido pode ainda ser recuperado e reutilizado. Neste estudo, óxidos mistos SiO2-ZrO2 foram obtidos a partir de uma solução comercial de Na2SiO3 (45%) e ZrOCl2 pelo método sol-gel. A influência da presença do surfactante brometo de cetiltrimetilamônio (CTAB) no meio reacional foi avaliada. Os materiais obtidos foram analisados por DSC e tratados termicamente em diferentes temperaturas (550, 600, 650 e 900 °C) e caracterizados por DRX, FTIR e MEV. O desempenho catalítico foi testado na reação de transesterificação do óleo de soja com metanol para a obtenção de biodiesel, com a conversão da reação avaliada por RMN-H. A análise térmica indica estabilidade térmica dos componentes até 850 °C. Após o tratamento térmico a 900 °C, as análises de DRX confirmam a cristalização da fase tetragonal da ZrO2. O FTIR indica que há a formação de algumas heteroligações Si-O-Zr durante a precipitação dos óxidos. As micrografias mostram que as partículas são formadas por aglomerados amorfos. As isotermas de adsorção dos óxidos tratados termicamente a 550 e 600 °C são do tipo IV, típicas de materiais mesoporos. Já os óxidos submetidos a 900 °C apresentam isotermas do tipo III, característica de materiais não porosos. Nenhuma das amostras apresentou atividade catalítica na reação de transesterificação do óleo de soja com metanol nas condições empregadas.Biodiesel is the second biofuel most used in the world. Currently, it is obtained of palm, soybean and canola oil, which represents up to 80% of the production cost. Aiming to reduce this cost, new catalysts have been developed to be used in processes with rich free fatty acids low cost feedstocks. ZrO2-based mixed oxides are known catalysts and its properties may present promising characteristics for acid catalysis of biodiesel. Furthermore, this oxide is a heterogeneous catalyst, and it can be recovered and recycled. In this study ZrO2-SiO2 mixed oxides are obtained by sol-gel method starting of a commercial Na2SiO3 solution (45%) and ZrOCl2. The influence of cetiltrimetilamonium bromide in the reactive medium is also investigated. The obtained material was analyzed by DSC and thermally treated at different temperatures (550, 600, 650 and 900 ° C). After that, it was characterized by RXD, FTIR and SEM. The catalytic activity was tested for the reaction of transesterification of soybean oil with methanol and the conversion was measured by H-RMN. The thermal analysis indicates thermal stability up until 850 °C. After thermal treatment at 900 °C de RXD analysis confirmed the tetragonal ZrO2 phase crystallization. The FTIR indicates the heterolinkages Si-O-Zr formation during the precipitation. The micrographs show particles formed by amorphous aggregates. The adsorption isotherms of mixed oxides treated at 550 and 600 °C are classified like type IV, typically of mesoporous materials. In the other hand, oxides submitted at 900 °C temperature have type III isotherms, characteristics of non-porous materials. None of the samples presented catalytic activity under the employed conditions

Volume estimation of an indoor space with LiDAR scanner

Three-dimensional scanning is a task of great importance for our modern society and has brought great advance when it comes to precision of inventory. These sensors measure and map the material surface continuously, allowing real-time inventory monitoring. As this process is very complex, most technologies are expensive, and even low-cost ones are a good investment option for the average user. Therefore, this work presents the simulation of a lowcost Time-of-Flight based 3D scanning system, that after a voxelization process, performs the volume estimation of an object filled indoor space. The system consists of a 2D LIDAR scanner that performs a 180º degrees sweep through a stepper motor.info:eu-repo/semantics/publishedVersio

Low-cost 3D LIDAR-based scanning system for small objects

Three-dimensional scanning is a task that is highly important for our modern society and this is translated by a wide area of knowledge that contains numerous approaches to this task. As this process is non-trivial, most of the technologies are expensive, with even the low-cost ones being a great investment for the regular user. Therefore, this work presents a low-cost LIDAR-based 3D scanning system that can perform 3D scans of small objects and reconstruct their digital STL models. The system consists of one rotating platform and a scanning arcshaped structure, which both are actuated by stepper motors.The project that gave rise to these results received the support of a fellowship from ”la Caixa” Foundation (ID 100010434). The fellowship code is LCF/BQ/DI20/11780028. This work also has been supported by FCT – Fundação para a Ciência e Tecnologia within the Projects UIDB/50014/2020 and UIDB/05757/2020.info:eu-repo/semantics/publishedVersio

A comparison of A* and RRT* algorithms with dynamic and real time constraint scenarios for mobile robots

There is an increasing number of mobile robot applications. The demanding of the Industry 4.0 pushes the robotic areas in the direction of the decision. The autonomous robots should actually decide the path according to the dynamic environment. In some cases, time requirements must also be attended and require fast path planning methods. This paper addresses a comparison between well-known path planning methods using a realistic simulator that handles the dynamic properties of robot models including sensors. The methodology is implemented in SimTwo that allows to compare the A* and RRT* algorithms in different scenarios with dynamic and real time constraint scenarios.This work is financed by the ERDF – European Regional Development Fund through the Operational Programme for Competitiveness and Internationalisation - COMPETE 2020 Programme within project POCI-01-0145-FEDER-006961, and by National Funds through the FCT – Fundac¸ao para ˜ a Ciencia e a Tecnologia (Portuguese Foundation ˆ for Science and Technology) as part of project UID/EEA/50014/2013.info:eu-repo/semantics/publishedVersio

Robot@factory lite competition: a digital twin approach for the AGV

Robotics competitions are environments that foster teamwork, AI, and technology development by encouraging students, researchers, and academics to test their solutions against each other. These competitions often challenge the competitors’ prototypes with tasks specifically designed to benchmark them with the current optimal solutions. During the prototype stages of a robot, the development costs and time spent are often higher than other stages, as changes in the prototype are frequent. Simulation is often used to reduce these variables as it allows flexibility in all development stages before transitioning to the real scenario. However, a digital twin can be used to increase even further flexibility and effectiveness. Digital twins are virtual representations of real assets, providing replication and prediction of real scenario events, and real-time monitoring of the real object. Thus, this paper presents the development of a digital twin of an automatic guided vehicle (AGV) to the Robot@Factory Lite competition and the tests performed to validate the approach.The project that gave rise to these results received the support of a fellowship from ”la Caixa” Foundation (ID 100010434). The fellowship code is LCF/BQ/DI20/11780028. This work is financed by National Funds through the Portuguese funding agency, FCT - Fundação para a Ciência e a Tecnologia within project UIDB/50014/2020.info:eu-repo/semantics/publishedVersio

Robot at factory 4.0: an auto-referee proposal based on artificial vision

The robotization and automation of tasks are relevant processes and of great relevance to be considered nowadays. This work aims to turn the manual action of assigning the score for the robotic competition Robot at Factory 4.0 by an automatic referee. Specifically, the aim is to represent the real space in a set of computational information using computer vision, localization and mapping techniques. One of the crucial processes to achieve this goal involved the adaptive calibration of the parameters of a digital camera through visual references and tracking of objects, which resulted in a fully functional, robust and dynamic system that is capable of mapping the competition’s objects accurately and correctly performing the referee’s tasks.This work is financed by National Funds through the Portuguese funding agency, FCT - Funda¸c˜ao para a Ciˆencia e a Tecnologia, within projects LA/P/0063/2020 and POCI-01-0247-FEDER-072638, co-funded by FEDER through COMPETE 2020. Authors acknowledge 5DPO RobotAtFactory team for making their time and robot available to conduct tests. The project that gave rise to these results received the support of a fellowship from “la Caixa” Foundation (ID 100010434). The fellowship code is LCF/BQ/DI20/11780028info:eu-repo/semantics/publishedVersio

A realistic simulation environment as a teaching aid in educational robotics

The experimental component is an essential method in Engineering education. Sometimes the availability of laboratories and components is compromised, and the COVID-19 pandemic worsened the situation. Resorting to an accurate simulation seems to help this process by allowing students to develop the work, program, test, and validate it. Moreover, it lowers the development time and cost of the prototyping stages of a robotics project. As a multidisciplinary area, robotics requires simulation environments with essential characteristics, such as dynamics, connection to hardware (embedded systems), and other applications. Thus, this paper presents the Simulation environment of SimTwo, emphasizing previous publications with models of sensors, actuators, and simulation scenes. The simulator can be used for free, and the source code is available to the community. Proposed scenes and examples can inspire the development of other simulation scenes to be used in electrical and mechanical Engineering projects. © 2022 IEEE.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CeDRI (UIDB/05757/2020 and UIDP/05757/2020) and SusTEC (LA/P/0007/2021). Thadeu Brito was supported by FCT PhD grant SFRH/BD/08598/2020 and Joao Braun received the ˜ support of a fellowship from ”la Caixa” Foundation (ID 100010434) with code LCF/BQ/DI20/11780028.info:eu-repo/semantics/publishedVersio

Three-dimensional scanning system based on a low-cost infrared sensor

Nowadays, with the availability of 3D printers, the scanners for objects are becoming increasingly present since they allow to replicate objects by 3D printing, especially for small scale sizes. However, the majority of these technologies are expensive, due to the complexity of this task. Therefore, this work presents a prototype of a low-cost 3D scanning system for small objects using a point cloud to stereolithography approach where it was already validated in simulation in previous work. This concept has a restriction that the objects must have a uniform shape, i.e, without discontinuities. The architecture is composed of two stepper motors, due to their precision, a rotating plate to allow 360 degrees scans and another rotating structure that allows the infrared distance sensor to scan the object from bottom to top (90 degrees). The prThis work has been supported by FCT - Fundação para a Ciência e Tecnologia within the Project Scope: UIDB/05757/2020. The project that gave rise to these results received the support of a fellowship from ”la Caixa” Foundation (ID 100010434). The fellowship code is LCF/BQ/DI20/11780028.info:eu-repo/semantics/publishedVersio

A reflexão como um instrumento de formação no PFCM

O Programa de Formação Contínua em Matemática para Professores dos 1.º e 2.º Ciclos do Ensino Básico (PFCM), com o objectivo de melhorar o ensino e as aprendizagens em Matemática e desenvolver atitudes mais positivas face a esta área do saber, pretende responder às necessidades dos professores participantes, partindo de questões relativas à concretização do currículo de Matemática na sala de aula e tendo um carácter continuado ao longo do ano lectivo. O PFCM constitui, assim, um instrumento de apoio e ajuda aos professores participantes na sua prática lectiva (planificação do trabalho, condução da aula, reflexão sobre o que foi feito) de modo a melhorar as suas actuações profissionais e, consequentemente, as aprendizagens matemáticas dos seus alunos. No anterior ano lectivo, o plano de formação desenvolvido pela Escola Superior de Educação de Bragança (ESEB), embora possibilitasse a abordagem de qualquer conteúdo de formação previsto, centrou-se em alguns domínios, nomeadamente, na clarificação ou aprofundamento de temas matemáticos, na discussão dos tipos e natureza das tarefas (exercícios, explorações, problemas, investigações; jogos, projectos), em aspectos da comunicação matemática, na utilização de materiais curriculares, e na construção dos portefólios, valorizando os registos escritos e reflexão. Nesta comunicação pretendemos discutir, com base na observação participante e na análise documental, situações e episódios ocorridos nas salas de aula que fundamentem aspectos do ensino e aprendizagem da Matemática destacados pelo plano de formação da ESEB e evidenciados quer pelos formadores quer pelos professores participantes, dando especial relevância à reflexão (pessoal e partilhada) sobre as experiências profissionais