Search Results (83)

Over millions of years of evolution, nature provided tools to optimize different functions in animals and plants. Different strategies observed in nature serve as models for solving complex engineering problems. Additive manufacturing (AM), also known as 3D printing, enables us to produce shapes that would not be possible with traditional subtractive manufacturing. In this way, it is possible to produce complex detailed shapes using an automatic process. Biomimetics involves drawing inspiration from nature and applying it to solve specific engineering challenges, often with the goal of optimization and enhanced performance. Three-dimensional printing enables the replication of complex natural shapes, opening new avenues for innovation. In this paper, we review the state of the art in biomimetics, including studies on mechanical properties, design strategies, manufacturing techniques, and the use of composites. Full article

The application of CAD/CAM technologies in modern production has revolutionized manufacturing processes, leading to significant improvements in precision, efficiency, and flexibility. These technologies enable the design and manufacturing of complex geometries with high accuracy, reducing errors and material waste. CAD/CAM integration streamlines workflows, enhances productivity, and facilitates rapid prototyping, accelerating the time-to-market for new products. Additionally, it supports customization and scalability in production, allowing for cost-effective small-batch and large-scale manufacturing. Without a 3D model of the product, it is not possible to use the advantages of applying advanced CAD/CAM technologies. Recognizing 3D models from engineering drawings is essential for modern production, especially for outsourcing companies in fluctuating market conditions, where the production process is organized with 2D workshop drawings on paper. This paper proposes a novel methodology for reconstructing 3D models from 2D engineering drawings, specifically those in DXF file format, leveraging a genetic algorithm. A core component of this approach is the representation of the 2D drawing as a symmetric adjacency matrix. This matrix serves as the foundational data structure for the genetic algorithm, enabling the evolutionary process to effectively optimize the 3D reconstruction. The experimental evaluation, conducted on multiple engineering drawing test cases (including both polyhedral and cylindrical geometries), demonstrated consistent convergence of the proposed GA-based method toward topologically valid and geometrically accurate 3D wireframe models. The approach achieved successful reconstruction in all cases, with fitness scores ranging from 1.1 to 112.2 depending on model complexity, and average execution times from 2 to 100 s. These results confirm the method’s robustness, scalability, and applicability in real-world CAD environments, while establishing a new direction for topology-driven 3D reconstruction using evolutionary computation. Full article

Knowledge visualization has gained significant research attention for its potential to facilitate knowledge construction through interactive graphics while minimizing cognitive load during information processing. However, limited research has examined the integration of knowledge visualization within highly interactive mixed-reality environments and its effects on user experiences and science, technology, engineering, and mathematics (STEM) sustainability. Drawing on the cognitive-affective model of immersive learning, this study investigates how learners’ user experiences, elicited by mixed-reality features and usability, influence their sustainable engagement with STEM learning through knowledge-visualization tools framed within the stimulus–organism–response model. A novel mixed-reality learning system was developed, with the user interface designed using concept maps to graphically visualize concept nodes and their interconnected relationships. A total of 136 learners from two high schools in China participated in an experiment on frictional physics using this novel system. Using structural equation modeling, the collected data were analyzed with partial least squares. The findings demonstrate that mixed-reality features of knowledge visualization (featured by 3D graphics, interface design, and operational functions), as well as usability (featured by the perceived usefulness of the concept map, perceived ease of use, and perceived usefulness of the system), have positive significant impacts on user experience (represented by satisfaction, perceived enjoyment, and attitude). Subsequently, positive user experiences have positive significant impacts on learners’ sustained intention to engage with STEM education. Further mediating analysis provides empirical evidence that positive user experiences, acting as a psychological enabler, mediate the relationship between system design and behavioral intention. The research model explains 65.2% of the variance for system usability, 53.4% for satisfaction, 51.5% for perceived enjoyment, 54.9% for attitude, and 63.2% for continuance intention. By fostering positive user experiences in STEM learning, this study offers valuable insights for educators and practitioners seeking to implement effective interactive knowledge visualizations to support sustainable STEM education and immersive learning. Full article

This research paper explores the impact of immersive virtual reality (IVR) on the teaching of conceptual design in engineering and architecture fields, focusing on the use of interactive 3D drawing tools in virtual and augmented reality environments. The study analyzes how IVR influences spatial understanding, idea communication, and immersive 3D sketching for industrial and architectural design. Additionally, it examines user perceptions of virtual spaces prior to physical construction and evaluates the effectiveness of these technologies through surveys administered to mechanical engineering students utilizing VR/AR headsets. A structured methodology was developed for students enrolled in an industrial design course, comprising four phases: initial theoretical instruction on ephemeral architecture, immersive 3D sketching sessions using Meta Quest 2 and Microsoft HoloLens 2 VR/AR headsets, detailed CAD modeling based on conceptual sketches, and immersive virtual tours to evaluate user perception and design efficacy. Ad hoc questionnaires specifically designed for this research were employed. The results indicate a positive reception to IVR, emphasizing its ease of use, intuitive learning process, and effectiveness in improving motivation, academic performance, and student engagement during the conceptual design phase in graphic engineering education. Full article

This paper presents an engineering design-based investigation of a historical invention: a single-cylinder horizontal high-pressure steam engine with a Corliss valve gear designed by Arnold Throp. The research, grounded in engineering drawing, has enabled an understanding of the operation of this invention based on a 3D CAD model derived solely from original plans published in the Model Engineer magazine in 1982 and reproduced by Julius de Waal in 2018. Contributing to the field of industrial archeology, our novel research utilizes CAD, engineering drawing, and mechanical engineering principles to revitalize historical inventions. Our methodology allows for a detailed analysis of the design and function of these significant technological advancements, ensuring their legacy is preserved. However, challenges were encountered during the geometric modeling process due to missing dimensions for certain components and errors in others. To address these issues, dimensional, geometric, and kinematic constraints (degrees of freedom) had to be applied to ensure that the 3D CAD model was coherent and functional, and an interference analysis also had to be conducted. Ultimately, symmetry was discovered in the governor’s structure and the arrangement of the four valves within the cylinder block, particularly in the mechanism that operates the inlet valves. This symmetry is essential to ensure that forces and movements are distributed evenly during the steam exchange within the cylinder, allowing for more balanced work, reduced vibrations, and the optimization of the overall efficiency of the invention. Full article

The massive integration of renewable electricity places significant regulatory pressure on urban power grids. This has also promoted the development of virtual power plant technology. The air conditioning systems of public buildings, as one of the main cores of virtual power plants, have flexible regulation capability that is difficult to quantify accurately, leading to slow development in practical engineering applications. This study proposes quantifying the flexible regulation capability of public building air conditioning systems based on heat and light transfer coefficient (HTC and LTC). Taking a public building in Shanghai as an example, this study combines 3D modeling and simulation and sliding window and correlation analysis techniques to investigate changes in influencing factors under different time periods, levels of insulation performance, and window-to-wall ratios. Drawing an analogy with energy storage batteries, two quantification indicators, response time (RT) and response energy loss (RL), are proposed and combined with heat and light transmission systems for nonlinear fitting. Finally, a sensitivity analysis of the impact of external environment and building performance is conducted. The results of sliding window and correlation analysis show that surface irradiance has the highest correlation with air conditioning energy consumption (over 0.8). However, through linear and nonlinear fitting, it was found that HTC can better characterize the two key indicators of RT and RL in air conditioning flexible adjustment, with fitting degrees (R²) of 80% and 72%, respectively. The results obtained from this study can provide a quantitative reference for quantification and response control research into the flexible regulation capability of public building air conditioning systems. Full article

The main idea of this work is based on the latest achievements in the commercialization of sodium-ion (Na-ion) batteries, which constitute a basis of analysis for military applications as energy storage systems. Technical, engineering, and ecological aspects were analyzed to find the optimal solution for using Na-ion batteries for military purposes. When selecting batteries for military applications, the following criteria are required: (a) they are more durable than standard batteries, (b) resistant to fire, (c) cannot explode, (d) cannot emit heat so as not to reveal their position, (e) equipped with safety elements and protective circuits to ensure safety, and (f) have the highest possible energy density, defined as the ratio of capacity to weight. The advantages and challenges of Na-ion batteries are discussed and compared to typical lithium-ion batteries, and also lithium iron phosphate, Ni-Cd, and Ni-MH batteries. The prospects for expanding the practical applications of Na-ion batteries in the military are presented. The unique properties of Na-ion batteries, such as their lower risk of ignition, more excellent thermal stability, and ability to work in extreme conditions, are essential from the point of view of military operations. Additionally, when considering environmental and logistical aspects, sodium-ion batteries may offer more sustainable and cost-effective solutions for the military. Therefore, this work aims not only to present the technological potential of these systems but also to draw attention to their strategic importance for the future of military operations. Battery discharge can result from leaving current receivers switched on or even from a drop in temperature. The discharge current should not exceed 1/10 of the battery capacity (1C). Discharging below the discharge voltage may result in irreversible damage. Sodium-ion batteries are safer to use than their lithium counterparts and allow for discharge to 0 V, eliminating the possibility of uncontrolled thermal discharge due to a short circuit (explosion, ignition), which is particularly important in the military. Full article

This paper presents an alternative method of producing 3D calligraphy products that have been created using integrated modern technologies, specifically reverse engineering and CNC machining. Traditionally, calligraphy is performed by hand on any suitable medium, such as on a wall or even on wood, which has drawbacks, i.e., it is time consuming and requires an original drawing or blueprint. To address these drawbacks, this new method utilizes integrated reverse engineering and CNC machining techniques to produce 3D calligraphy products without the need for an original drawing or blueprint, significantly reducing time consumption. Full article

This study performed a 3D CFD analysis on a GP3 rotary engine to determine the stroke and flow characteristics and examine the thermal- and flow-related design factors’ validity. The 3D CFD analysis was performed using the CONVERGE program, utilizing the automatic grid generation function based on the 3D engine design drawing, which is suitable for a rotating rotary engine geometry. The target species and error tolerance were selected based on the GRI-Mech 3.0 full reaction mechanism to validate the reaction model and define a reasonable range of target species and error tolerances. The RNG k-ε turbulence and SAGE combustion models were also employed to analyze the four-stroke characteristics for the GP3 engine by visualizing the internal flow. The various outcomes confirmed the rotary engine’s unique characteristics and were reasonably interpreted to validate the engine design factors. In particular, the EGR phenomenon in the intake and exhaust port overlap area and the interference phenomenon in the port overlap area between adjacent cylinders are unique to the engine, and were rationally analyzed to more accurately predict the engine’s performance. The results of this study regarding the flame quenching regions indicated power and efficiency, and the emission characteristics can be used to validate the design parameters. Full article

The construction industry in Kuwait is experiencing a transformative shift with the adoption of Building Information Modeling (BIM) technologies, particularly BIM 6D for sustainability analysis and 7D for facility management. This study investigates the integration of these dimensions to address sustainability challenges in Kuwait’s construction sector, aligning practices with the United Nations’ Sustainable Development Goals (SDGs). Through qualitative interviews with 15 stakeholders—including architects, engineers, and contractors—and analysis of industry reports, policies, and case studies, the research identifies both opportunities for and barriers to BIM adoption. While BIM offers significant potential for lifecycle analysis, waste reduction, and energy efficiency, its adoption remains limited, with only 27% of construction waste recycled. Challenges include high initial costs, a shortage of skilled personnel, and resistance to change. The study highlights actionable strategies, including enhanced regulatory frameworks, university curriculum integration, and professional training programs led by the Kuwait Society of Engineers, to address these barriers. It also emphasizes the critical role of collaboration among government bodies, industry leaders, and institutions like the Kuwait Institute for Scientific Research. Drawing from successful international BIM projects, the findings offer a practical framework for improving sustainability in arid regions, positioning Kuwait’s experience as a model for other Middle Eastern and North African countries. This research underscores the transformative role of BIM technologies in advancing global sustainable construction practices and achieving a more efficient and eco-friendly future. Full article

Building information modeling (BIM) has proven to be a valuable technology in the fields of architecture, construction management, and maintenance management. However, its full implementation in structural engineering remains unfulfilled due to the persistent use of outdated design methods. Insufficient automation in the design process could lead to structural defects, construction rework, and structural clashes, each of which can have significant financial implications. Given the inherent complexity of large-scale construction projects, manual structural design and detailing are challenging tasks and are prone to human errors. This paper presents a novel BIM framework that leverages BIM, Industry Foundation Classes (IFC), Python scripting, the IfcOpenShell library, and Octave programming to automate the design of reinforced concrete (RC) slabs, benefiting design professionals and contractors by integrating automated processes into project workflows. The framework achieved a 40% reduction in design time and a 25% decrease in human errors, as demonstrated through case studies. In this study, a 3D structural model in BIM software is firstly created, extracting slab geometrical data that are linked to Microsoft (MS) Excel/.csv and Octave spreadsheets via Python and IfcOpenShell. Midspan and end span moment coefficients and floor perimeter data following Indian standards are then gathered in Octave, and this information is further processed with Python scripts. Octave programming is used to determine the most accurate, reliable, and economical design for the slab and its detailing. This design information is then pushed back to BIM software via FreeCAD using Python coding, which can be used to develop bar bending scheduling and 2D drawings of the reinforcement details. The proposed framework is validated through case studies, demonstrating its effectiveness in reducing design time, minimizing human errors, and improving overall project efficiency. The core finding of this research is an automated approach that offers a cost-effective and accurate solution to the limitations of traditional RC slab design, addressing structural errors and reducing rework through seamless BIM integration. This research presents a novel contribution to the integration of structural design, construction processes, and operational aspects within BIM. The findings highlight the potential for further advancements in BIM adoption, particularly in addressing the lag in structural engineering applications compared to architecture. Full article

The long-standing practice of document-based engineering has resulted in the accumulation of a large number of engineering documents across various industries. Engineering documents, such as 2D drawings, continue to play a significant role in exchanging information and sharing knowledge across multiple engineering processes. However, these documents are often stored in non-digitized formats, such as paper and portable document format (PDF) files, making automation difficult. As digital engineering transforms processes in many industries, digitizing engineering documents presents a crucial challenge that requires advanced methods. This research addresses the problem of automatically extracting textual content from non-digitized legacy engineering documents. We introduced an optical character recognition (OCR) system for text detection and recognition that leverages transformer-based generative deep learning models and transfer learning approaches to enhance text recognition accuracy in engineering documents. The proposed system was evaluated on a dataset collected from ships’ engineering drawings provided by a U.S. agency. Experimental results demonstrated that the proposed transformer-based OCR model significantly outperformed pretrained off-the-shelf OCR models. Full article

While our world consistently presents complicated, interdisciplinary problems with STEM foundations, most pre-university curricula do not encourage drawing on multidisciplinary knowledge in the sciences and engineering to create solutions. We developed an instructional approach, Iterative Science and Engineering (ISE), that cycles through scientific investigation and engineering design and culminates in constructing a solution to a local environmental challenge. Next, we created, revised, and evaluated a six-week ISE curricular program, Invasive Insects, culminating in 6th–9th-grade students building traps to mitigate local invasive insect populations. Over three Design-Based Research (DBR) cycles, we gathered and analyzed identical pre and post-test data from 554 adolescents to address the research question: what three-dimensional (3D) science and engineering knowledge do adolescents demonstrate over three DBR cycles associated with a curricular program following the Iterative Science and Engineering instructional approach? Results document students’ significant statistical improvements, with differential outcomes in different cycles. For example, most students demonstrated significant learning of 3D science and engineering argument construction in all cycles—still, students only significantly improved engineering design when they performed guided reflection on their designs and physically built a second trap. Our results suggest that the development, refinement, and empirical evaluation of an ISE curricular program led to students’ design, building, evaluation, and sharing of their learning of mitigating local invasive insect populations. To address complex, interdisciplinary challenges, we must provide opportunities for fluid and iterative STEM learning through scientific investigation and engineering design cycles. Full article

Metallization, a process for applying anti-corrosion coatings, has advantages over hot-dip galvanizing, such as reduced thermal stress and the ability to work “in situ”. This process consists of the projection of a protective metal as coating from a wire as application material, and this wire is obtained by multi-stage wiredrawing. For the metallization process, a zinc–aluminum alloy wire obtained by this process is used. This industrial process requires multiple stages/dies of diameter reduction, and determining the optimal sequence is complex. Thus, this work focuses on developing models with the aim of designing and optimizing the wiredrawing process of zinc–aluminum (ZnAl) alloys, specifically ZnAl15%, used for anti-corrosion applications. Both analytical models and numerical models based on the finite element method (FEM) and implemented by computer-aided engineering (CAE) software Deform 2D/3D v.12, enabled the prediction of the drawing stress and drawing force in each drawing stage, producing values consistent with experimental measurements. Key findings include the modeling of the material behavior when ZnAl15% wires were subjected to the tensile test at different speeds, with strain rate sensitivity coefficient m = 0.0128, demonstrating that this type of alloy is especially sensitive to the strain rate. In addition, the optimal friction coefficient (µ) for the drawing process of this material was experimentally identified as µ = 0.28, the ideal drawing die angle was determined to be 2α = 10°, and the alloy’s deformability limit has been established by a reduction ratio r ≤ 22.5%, which indicates good plastic deformation capacity. The experimental results confirmed that the development of the proposed models can be feasible to facilitate the design and optimization of industrial processes, improving the efficiency and quality of ZnAl15% alloy wire production. Full article

Biomimetics is the science of imitating nature’s designs and processes to create innovative solutions for various fields, including dentistry and craniofacial reconstruction. In these areas, biomimetics involves drawing inspiration from living organisms/systems to develop new materials, techniques, and devices that closely resemble natural tissue structures and enhance functionality. This field has successfully demonstrated its potential to revolutionize craniofacial procedures, significantly improving patient outcomes. In dentistry, biomimetics offers exciting possibilities for the advancement of new dental materials, restorative techniques, and regenerative potential. By analyzing the structure/composition of natural teeth and the surrounding tissues, researchers have developed restorative materials that mimic the properties of teeth, as well as regenerative techniques that might assist in repairing enamel, dentin, pulp, cementum, periodontal ligament, and bone. In craniofacial reconstruction, biomimetics plays a vital role in developing innovative solutions for facial trauma, congenital defects, and various conditions affecting the maxillofacial region. By studying the intricate composition and mechanical properties of the skull and facial bones, clinicians and engineers have been able to replicate natural structures leveraging computer-aided design and manufacturing (CAD/CAM) and 3D printing. This has allowed for the creation of patient-specific scaffolds, implants, and prostheses that accurately fit a patient’s anatomy. This review highlights the current evidence on the application of biomimetics in the fields of dentistry and craniofacial reconstruction. Full article