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- Manufacture wing models to analyze air fluid flow in wind tunnel using a 3D printerPublication . Ariati, Ronaldo; Rocha, João; Ribeiro, J.E.Aerodynamics is a field that is very present in our daily lives, but we are unaware of it. One of the best examples of this is our car, which was not designed at random. This study of aerodynamics has been very important in recent years in several areas, namely motor racing and aeronautics, which is so useful for us when we want to travel. This study consists of developing prototypes of aircraft wings for wind tunnel simulation and numerical simulations due to the high demand to be able to better develop cars, aircraft, and all means involving aerodynamics. The prototypes were created using the SolidWorks CAD software, and additive printing was done in a 3D printer using PLA filament.
- Manufacture and development of a 3D printing handle for laparoscopic applicationPublication . Ariati, Ronaldo; Rocha, Catarina; Ribeiro, J.E.; Rocha, Joãoapproximately a century ago and due to its advantages, such as the rapid recovery of patients, it has become the focus of several studies for the improvement of the equipment and the technique. However, the equipment has a serious ergonomic problem in its configuration, which causes several musculoskeletal problems for surgeons causing, for example, muscle pain, temporary paresthesia, and fatigue, among other long-term pathologies. The study and development of new handle models and the reduction of the forces required for their manipulation are of fundamental importance in the field of laparoscopy. In this sense, this work presents the integration of the product development method of Pahl and Beitz (2007) and the DSR (Design Science Research) method for the development of a laparoscopic instrument, to be applied in tweezers and scissors, that meets the ergonomic requirements presented in the literature.
- 2nd. International Workshop on Additive Manufacturing and Sustainability (IWAM): book of proceedingsPublication . Rocha, João; Ribeiro, J.E.; Santos, Jorge; Lima, Rui A.In recent years, the manufacturing processes have undergone a profound transformation, driven by the rapid evolution of additive manufacturing (AM) technologies. What began as a tool primarily for prototyping through stereolithography has now expanded into a versatile and innovative field capable of producing functional, end-use components across a wide range of industries. From fused deposition modeling (FDM) to selective laser melting (SLM) and beyond, AM has unlocked new possibilities in design, material utilization, and production efficiency. Today, additive manufacturing encompasses an extensive array of materials, including metals, polymers, paper, and even biological tissues, enabling applications that span from the mechanical industry to the biomedical sector. One of the most compelling aspects of additive manufacturing is its potential to drive sustainability in modern production processes. Unlike traditional subtractive methods, which often generate significant material waste, AM builds components layer by layer, minimizing excess material and promoting resource efficiency. Furthermore, the ability to use eco-friendly and recyclable materials aligns with global efforts to reduce environmental impact. AM also supports the production of complex, customized parts on demand, reducing the need for large inventories and long-distance transportation, thereby lowering carbon emissions. By optimizing resource use and enabling more efficient production cycles, additive manufacturing is emerging as a cornerstone of sustainable manufacturing practices. This proceeding book arrests the latest advancements, challenges, and opportunities in the field of additive manufacturing, with a particular focus on its transformative potential and contributions to sustainability. The works presented here reflect the interdisciplinary nature of AM, showcasing innovative techniques, materials, and applications that are shaping the future of manufacturing. From cutting-edge research to real-world case studies, this collection aims to inspire further exploration and collaboration, driving the adoption of additive manufacturing as a key enabler of sustainable industrial progress. We invite readers to probe into these pages and discover how AM is not only redefining manufacturing but also paving the way for a more sustainable and efficient future.
- Construction of an optimized 3D Printer, programmed by Arduino and designed in SolidWorks softwarePublication . Trindade, Raul Manuel; Lopes, Isabel Maria; Santos, Jorge; Rocha, JoãoThe 3D printer is a prototyping machine capable of producing three-dimensional objects, distributed in 3D software, which are built after layer through an additive process. This project aims to develop a low-cost open-source 3D Printer controlled by Arduino. It also aims to deepen the topic of rapid prototyping and provide the community, internal and external, of the Polytechnic Institute of Bragança (IPB), with a base for developing these printers so as to benefit from the study of new technologies and their replication. The most common and economical model, of a 3D printer, uses the technique of modeling by fusion and deposition (FDM - Fused Deposition Modeling), which is the base technology of our project. At the beginning of the project, we were proposed to design a 3D printer. In this there was the electronic/programming part already validated, with the need to build the mechanical part of it. Thus, we proposed to continue the base of the existing project, having carried out all the mechanical modeling of the printer and validating the design of the various parts that had to be raised in order to meet the various requirements this one demanded. There was also a survey of suppliers of various parts on the market from which an extensive list of references, suppliers, values, quantities, and forms of acquisition was drawn up. In order to make the final physical assembly possible, they were machined as aluminum parts, obtaining structural strength and reliability of the set. Aluminum parts were marked in order to able to use the “leftovers” existing in the mechanical workshop and thus manage to reduce and consolidate the final cost of the project.[3].
- Integration of design failure mode and effects analysis (DFMEA) and design science research (DSR) to ergonomic design of a laparoscopic handlePublication . Lira Nuñez, David; Rocha, JoãoThe problems associated with laparoscopic surgery and the surgeon’s musculoskeletal health have been studied since the beginning of the century. The fatigue, pain, static and forced body postures, and pressure areas are some of the problems that can be caused by the handles lack of ergonomics. For this reason, this work has the objective to develop an ergonomic handle for laparoscopic surgery applying the Design Science Research (DSR) method integrated with the Engineering Design approach of Pahl & Beitz, using Design Failure Mode and Effects Analysis (DFMEA) technique. The main result of this work was the prototype of a laparoscopic handle that follows the several guidelines presented in the literature for a correct ergonomic handle
- Análise do stick de hóquei em patins para futuro reforço estruturalPublication . Fernandes, Joana Filipa Teixeira; Queijo, Luis; Rocha, Joãopatins, daí ter surgido o interesse pelo estudo do remate deste desporto. O objetivo deste estudo foi criar condições para analisar o comportamento do stick durante um remate de hóquei em patins. Para tal, recorreu-se a técnicas videográficas de alta velocidade sendo realizadas filmagens de todo o remate. Estas filmagens foram feitas no Laboratório de Tecnologia Biomédica – ESTIG. Os ensaios experimentais realizados, tiveram por base um mecanismo de testes de stick de hóquei em patins desenvolvido no âmbito deste estudo. Desenvolvido o mecanismo, foi necessário fazer a simulação do mesmo, utilizando- se o programa SolidWorks® Dassault Systems ver.2015/2016 - Simulation, antes de se passar à construção, uma vez que era necessário saber se o material a utilizar – aço de construção AISI 1020, suportaria os esforços mecânicos que lhe seriam aplicados. Feitos os ensaios, foi necessário tratar as imagens para de seguida se poderem apresentar os resultados obtidos. Analisando as imagens obtidas em alta-velocidade, foi possível obter uma melhor perceção do comportamento do stick em função da força que lhe é aplicada. De acordo com os cálculos feitos, é de esperar que, com melhorias no mecanismo, nomeadamente na mola e no rolamento, os resultados sejam mais similares aos descritos na literatura. O remate que o mecanismo proporcionou assemelhou-se ao executado por atletas. Os resultados obtidos nos ensaios podem ser fundamentais para o estudo dos futuros materiais a aplicar nos sticks de hóquei em patins, permitindo o seu reforço estrutural.
- Optimization of hemp (Cannabis sativa L.) mechanical and physical propertiesPublication . Bueno, Guilherme Irigoyen; Ribeiro, J.E.; Costa, Roberto Germano; Rocha, JoãoNatural fibers are an alternative to the traditional synthetic fibers used for industrial applications and as reinforcement of composites material. Compared to synthetic fibers, the advantages of using natural fibers are their renewability, recyclability, low density, availability in large amounts and low cost [1]. Hemp fiber is used in many applications, it is particularly attractive to reinforcement of composites materials [2]. In this context, a mechanical and physical characterization has been made with hemp fibers grew in Bragança and Mirandela, regions from Portugal, in different conditions of nitrogen fertilization, sowing density, extraction method, and grew location. The objective of the study was to assess the effects of these parameters for optimizing the mechanical properties of hemp fibers. Tensile strength and Young's modulus were determined according to ASTM C1557 [3], density tests were made using a water pycnometer. Average value for tensile strength was 565.3 ± 167.0 MPa, average density was 1.65 ± 0.25 g cm-3 and average Young’s modulus was 92.4 ± 7.4 GPa. A statistical analysis of all parameters was made using ANOVA. The influence of all parameters was determined, the most influent parameter was extraction method and the combined effect of sowing density and nitrogen fertilization, with high influence in specific tensile strength and tensile strength, respectively. Optimal parameters for higher tensile strength were obtained for sowing density of 100 Kg ha-1, nitrogen fertilization of 50 Kg ha-1, extracted with water, cultivated in Bragança. Lower density values were obtained for sowing density of 25 Kg ha-1, nitrogen fertilization of 100 Kg ha-1, extracted with water, cultivated in Bragança. Higher Young's Modulus was determined for fibers from Bragança, with sowing density of 50 Kg ha-1, nitrogen fertilization of 50 Kg ha-1 and extracted with water.
- Conceção e projeto de um centro de maquinagem CNC de 5 eixosPublication . Cachada, Ana; Queijo, Luis; Rocha, JoãoResumo Este trabalho consistiu em conceber e projetar um centro de maquinagem CNC com 5 eixos adequado à maquinagem de materiais macios, como por exemplo poliuretano. Este centro maquinagem deve apresentar uma volumetria de trabalho máxima de 0,5x0,5x0,5 m3. O desenvolvimento deste trabalho passou pela análise de diversas estruturas, passiveis de serem utilizadas como estrutura base de um centro de maquinagem com 5 eixos, cálculo dos esforços a que a estrutura está sujeita, cálculo das velocidades de trabalho e cálculo da massa máxima dos materiais a maquinar. Definidas as condições iniciais do modelo foi necessário selecionar os perfis a utilizar na estrutura da máquina-ferramenta e ainda todos os elementos integrantes dos sistemas de movimentação linear e rotativa, como fusos, motores, rolamentos, engrenagens, polias, entre outros. Além dos elementos standard selecionados foi essencial proceder à conceção de elementos de ligação e suporte criados especificamente para o equipamento, como apoios para os motores e fusos, cantoneiras, entre outros. Posteriormente, realizaram-se simulações estáticas para verificar se todos os componentes suportam os esforços que lhe são impostos e perceber quais as deformações sofridas por estes. Através da análise das deformações e dos deslocamentos mínimos conseguidos foi possível determinar qual a exatidão do equipamento. Por fim, com base em orçamentos e preços estimados foi efetuada uma estimativa de custo total do equipamento.
- Estudo da influência do calçado sobre o músculo gastrocnémio através de eletromiografiaPublication . Mota, Ana Carolina Costa; Ribeiro, Andreia; Sampaio, Cátia; Vieira, Dalila; Rocha, JoãoEste trabalho foi realizado no âmbito da unidade curricular Tecnologias de Reabilitação pertencente ao mestrado de Tecnologias Biomédicas do Instituto Politécnico de Bragança. Teve como principal objetivo analisar os estímulos musculares através da eletromiografia durante a marcha com diferentes tipos de calçado. O calçado utilizado possuía diferentes solas e onde se pretendia verificar qual exigia menor esforço muscular durante a marcha. Para tal recorreu-se ao software BIOPAC, presente no Laboratório de Tecnologias Biomédicas, para a recolha dos sinais eletromiográficos. A marcha foi efetuada numa passadeira a velocidade constante de 3km/h. Segundo a literatura, a força total existente na contração muscular e o número de fibras musculares ativadas durante a marcha estão diretamente relacionadas com a amplitude do sinal eletromiográfico. Os principais resultados obtidos neste estudo foram que com a utilização de sandálias com tacão registou-se um valor máximo de amplitude e de área e ainda que no caso das sandálias sem tacão possuem valores inferiores de amplitude e área. Os resultados obtidos podem conter erros devido à influência do movimento dos cabos, que têm como função a transferência dos dados adquiridos nos sensores para o suporte digital (computador), pois pode-se estar a adicionar ruído ao sinal. Outro fator que pode contribuir para um resultado menos fiável foi o facto de não se ter limpo a pele com álcool, bem como a colocação dos elétrodos não ter sido precisa. De notar ainda que os elétrodos utilizados foram da marca DAHLHAUSEN (Ag/AgCl), os quais podem não ter sido a melhor escolha para o estudo efetuado. O erro da passadeira também pode exercer uma influência sobre os resultados.
- Análise de um stick de hóquei em patins em remate para futuro desenvolvimento de soluções de reforço estruturalPublication . Fernandes, Joana Filipa Teixeira; Queijo, Luis; Rocha, JoãoDo ponto de vista da engenharia, existe pouca informação sobre o hóquei em patins [1], daí ter surgido o interesse pelo estudo do remate deste desporto. O objetivo desta investigação foi criar condições para analisar o comportamento do stick durante um remate de hóquei em patins, recorrendo a técnicas videográficas. Através da análise das imagens obtidas em alta-velocidade, foi possivel obter uma melhor perceção do comportamento do stick em função da força que lhe é aplicada.