Search Results (30)

Parallel-Computing Topology Optimization (PCTO) has gained importance, especially with the advancement of additive manufacturing (AM), due to its ability to tackle high-dimensional, high-resolution challenges. PCTO is highly relevant to sustainable manufacturing processes and technologies, enabling resource-efficient designs, reduced emissions, and advancements in Industry 4.0 integration. However, PCTO poses difficulties for newcomers or researchers, mainly because of its reliance on non-traditional computing environments and the limited availability of high-performance computing (HPC) resources. Addressing this, the study introduces TopADDPi, a Raspberry Pi-based cluster system, which has been purpose-built to facilitate learning and research in PCTO. It provides detailed instructions for assembling and configuring a Raspberry Pi cluster, with a focus on cost-effectiveness and ease of use. The study thoroughly investigates how different hardware and software configurations affect computing efficiency. In addition, through extensive numerical testing, the performance, energy consumption, and environmental impact of the Raspberry Pi cluster are benchmarked against conventional computing systems. The findings demonstrate the cluster’s advantages in handling parallel computing, its indispensable role in debugging, its remarkable energy efficiency, and its significantly reduced carbon footprint compared to conventional systems. These attributes establish the Raspberry Pi cluster as an invaluable tool for both educational and research applications in structural engineering, offering an affordable, sustainable, and indispensable solution for PCTO. Full article

This paper presents the world’s smallest two-phase flux-switching motor (FSM), featuring a four-pole stator and a two-pole rotor with a non-uniform air gap design. The FSM offers several advantages, including a compact size, simple structure, and ease of manufacturing, making it suitable for future micromachine applications. The motor has an outer stator diameter of 8 mm, an outer rotor diameter of 4 mm, and a stack length of 5 mm. This research employs a topological method and JMAG-Designer Ver.22.0 electromagnetic analysis software to enhance the rotor design for high output torque and low torque ripple. The final design achieves an average torque of 174 μN-m and a torque ripple of 40%, which is lower than those of any two-phase motor reported in the literature. The two-phase FSM has been fabricated, assembled, and tested to demonstrate its feasibility. Full article

With the advancement of lead–bismuth fast reactors, there has been increasing attention directed towards the design of and manufacturing technology for electromagnetic pumps employed to drive liquid lead–bismuth eutectic (LBE). These electromagnetic pumps are characterized by a simple structure, effective sealing, and ease of flow control. They exploit the excellent electrical conductivity of liquid metals, allowing the liquid metal to be propelled by Lorentz forces generated by the traveling magnetic field within the pump. To better understand the performance characteristics of electromagnetic pumps and master the techniques for integrated manufacturing and performance optimization, this study conducted fundamental research, development of key components, and the assembly of the complete pump. Consequently, an annular linear induction pump (ALIP) suitable for liquid lead–bismuth eutectic was developed. Additionally, within the lead–bismuth thermal experimental loop, startup and preheating experiments, performance tests, and flow-head experiments were conducted on this electromagnetic pump. The experimental results demonstrated that the output flow of the electromagnetic pump increased linearly with the input current. When the input current reached 99 A, the loop achieved a maximum flow rate of 8 m³/h. The efficiency of the electromagnetic pump also increased with the input current, with a maximum efficiency of 5.96% during the experiments. Finally, by analyzing the relationship between the flow rate and the pressure difference of the electromagnetic pump, a flow-head model specifically applicable to lead–bismuth electromagnetic pumps was established. Full article

The research work presents a novel voxel-type soft amphibious robot based on an assembly of origami flexiballs. The geometric and elastic constitutive models of the origami flexiball are theoretically established to elucidate its intricate deformation mechanism. Especially, the zero-energy storage phenomenon and the quasi-zero-stiffness characteristic are revealed to prove that the origami flexiball is suitable for serving as soft robotic components. As a proof of concept, fourteen origami flexiballs are interconnected to form a quadruped robot capable of walking or crawling in both underwater and terrestrial environments, including flat surfaces and sandy terrain. Its adaptability across multiple environments is enhanced by the origami polyhedra-inspired hollow structure, which naturally adjusts to underwater conditions such as hydrostatic pressure and currents, improving stability and performance. Other advantages of the voxel-type soft amphibious quadruped robot include its ease of manufacture using 3D printing with accessible soft elastic materials, ensuring rapid and cost-effective fabrication. We anticipate its potentially versatile applications, including underwater pipeline inspections, offshore maintenance, seabed exploration, ecological monitoring, and marine sample collection. By leveraging metamaterial features embodied in the origami polyhedra, the presented voxel-type soft robot exemplifies an innovative approach to achieving complex functionalities in soft robotics. Full article

Shape-memory alloys have various applications in different fields including medicine, robotics, aeronautics, and micro-electromechanical systems. This paper discusses shrink-fit joints formed by shape-memory alloy elements and their application for the axial fixation of mechanical components. The use of shape-memory alloys gives the shrink-fits some specific features: ease of assembly, insensitivity to tooling and human error, chemical resistance, low cost, etc. The friction force created between the components is experimentally investigated as a function of two parameters—the substrate diameter and the surface roughness (Ra) of one of the joined elements. The results of the experiments are presented analytically and graphically. Conclusions are drawn regarding the behavior of the studied shrink-fits. They can be beneficial to any engineering project making it less sensitive to manufacturing variations. Full article

Build-up-edge (BUE), high-temperature machining and tool wear (TW) are some of the problems associated with difficult-to-machine materials for high-temperature applications, contributing significantly to high-cost manufacturing and poor tool life (TL) management. A detailed review of non-traditional machining processes that ease the machinability of INCONEL^®, decrease manufacturing costs and suppress assembly complications is thus of paramount significance. Progress taken within the field of INCONEL^® non-conventional processes from 2016 to 2023, the most recent solutions found in the industry, and the prospects from researchers have been analysed and presented. In ensuing research, it was quickly noticeable that some techniques are yet to be intensely exploited. Non-conventional INCONEL^® machining processes have characteristics that can effectively increase the mechanical properties of the produced components without tool-workpiece contact, posing significant advantages over traditional manufacturing. Full article

A flow-through biosensor system for the determination of uric acid was developed on the platform of flow-through electrochemical cell manufactured by 3D printing from poly(lactic acid) and equipped with a modified screen-printed graphite electrode (SPE). Uricase was immobilized to the inner surface of a replaceable reactor chamber. Its working volume was reduced to 10 μL against a previously reported similar cell. SPE was modified independently of the enzyme reactor with carbon black, pillar[5]arene, poly(amidoamine) dendrimers based on the p-tert-butylthiacalix[4]arene (PAMAM-calix-dendrimers) platform and electropolymerized 3,7-bis(4-aminophenylamino) phenothiazin-5-ium chloride. Introduction of the PAMAM-calix-dendrimers into the electrode coating led to a fivefold increase in the redox currents of the electroactive polymer. It was found that higher generations of the PAMAM-calix-dendrimers led to a greater increase in the currents measured. Coatings consisted of products of the electropolymerization of the phenothiazine with implemented pillar[5]arene and PAMAM-calix-dendrimers showing high efficiency in the electrochemical reduction of hydrogen peroxide that was formed in the enzymatic oxidation of uric acid. The presence of PAMAM-calix-dendrimer G2 in the coating increased the redox signal related to the uric acid assay by more than 1.5 times. The biosensor system was successfully applied for the enzymatic determination of uric acid in chronoamperometric mode. The following optimal parameters for the chronoamperometric determination of uric acid in flow-through conditions were established: pH 8.0, flow rate 0.2 mL·min⁻¹, 5 U of uricase per reactor. Under these conditions, the biosensor system made it possible to determine from 10 nM to 20 μM of uric acid with the limit of detection (LOD) of 4 nM. Glucose (up to 1 mM), dopamine (up to 0.5 mM), and ascorbic acid (up to 50 μM) did not affect the signal of the biosensor toward uric acid. The biosensor was tested on spiked artificial urine samples, and showed 101% recovery for tenfold diluted samples. The ease of assembly of the flow cell and the low cost of the replacement parts make for a promising future application of the biosensor system in routine clinical analyses. Full article

Modern economic, social and environmental challenges require a new type of construction that ensures resilience, low construction costs and ease of maintenance. Material production, manufacturing of structural elements and final assembly should minimise the environmental impacts, such as greenhouse emissions and waste production. This review aims to identify the key routes of research and development required to address the environmental challenges the construction industry faces. It outlines recent advances and highlights the rising opportunities. The strategies with great perspectives include 3D concrete printing, prefabrication and modular construction, mortarless construction, development and utilization of sustainable, smart and composite materials, renewable energy systems and automation technologies including the Digital Twin technology. Hybrid approaches that combine traditional and novel construction methods present the greatest potential. Overall, collaboration between stakeholders is crucial in driving innovation and successfully implementing these advancements. Full article

Product engineering involves the design and development of new products or the improvement of existing products to efficiently meet market needs and ensure high quality. Design for Excellence (DfX) concepts, such as Design for Manufacturing, Design for Assembly, Design for Reliability, Design for User Experience, Design for Testability, and Design for Security, are essential in product engineering. These concepts enhance manufacturability, ease of assembly, and serviceability, thereby improving overall product performance and user experience. Integrating sustainability principles into product engineering practices is crucial due to growing concerns about environmental sustainability. Sustainability involves responsible resource use, waste and emission reduction, and consideration of social and economic impacts. Adopting sustainable practices is essential for addressing global challenges like climate change, resource depletion, and pollution. Consequently, sustainability has become a significant factor for businesses and government policies worldwide. Product engineering possesses significant potential for contributing to sustainability goals. In this view, this paper discusses a new approach called “Design for Sustainability (DfS)” that focuses on developing sustainable products. The paper discusses the various steps involved in implementing DfS in the product engineering process, highlighting its importance and benefits. By implementing DfS practices, businesses can create innovative and marketable products that minimize environmental impact while meeting consumer demands. Full article

Design for manufacturing, assembly, and disassembly is critical in manufacturing. Failing to consider this aspect can lead to inefficient performance and material overuse, which significantly impact cost and construction time. Production with a high capability for recycling is a method to help conserve natural resources. This article is compiled with a review method and has evaluated the recent and related articles that consider design for production, design for assembly and disassembly, design for recycling and reuse, and sustainable design. This review, moreover, aims to focus more on the relationship between using a design approach for production and assembly in the ease of recycling and preservation of raw materials and reuse of materials. The survey for the design methods conducive to achieving ease of recycling is one of the crucial issues that fill the gap in the literature in this respect. Google Scholar was selected as a database, and the keywords “DFMA”, “design”, “facility of recycling”, “recycling”, “EoL”, and “product design” were considered to collect related articles. At first, 115 articles were identified, and 26 articles with a high focus on the subject were selected. Finally, nine articles were considered for final evaluation, 33% of which focused on the design approach for assembly. Many of the issues evaluated are about reducing the number of components and reducing complexity in design, materials, environmental impact, manufacturing cost and time, repair, reuse, end-of-life, remanufacturing, recycling, and non-recyclable waste. According to the mentioned materials, compiling a category of crucial information along with sustainable design indicators and approaches, as well as identifying and explaining the strategic actions of the researchers in this field, will benefit the experts and help them to obtain better insight into environmentally friendly production. This, moreover, helps to substantiate a circular economy by increasing the percentage of recycling materials and parts with various methods and reducing costs and the use of raw materials. Full article

Pneumatic actuators are of great interest for device miniaturization, microactuators, soft robots, biomedical engineering, and complex control systems. Recently, multi-material actuators have become of high interest to researchers due to their comprehensive range of suitable applications. Three-dimensional (3D) printing of multi-material pneumatic actuators would be the ideal way to fabricate customized actuators, but so far, this is mostly limited to deposition-based methodologies, such as fused deposition modeling (FDM) or Polyjetting. Vat-based stereolithography is one of the most relevant high-resolution 3D printing methods but is only rarely utilized in the multi-material 3D printing of materials. This study demonstrated multi-material stereolithography using combinations of materials with different Young’s moduli, i.e., 0.5 MPa and 1.1 GPa, for manufacturing pneumatic actuators and microactuators with a resolution as small as 200 μm. These multi-material actuators have advantages over single-material actuators in terms of their deformation controllability and ease of assembly. Full article

Steel structures that benefit from having lightweight, ductility, and seismic behaviors are capable of improving the overall performance of civil engineering in environmental protection, project quality, process management, and ease of construction, making the procedure more feasible for builders. The application of steel structure techniques has been widely used in bridges, tall buildings, and complex projects around the world. Increasing demand for planning and design has led to structural projects upgrading in structural complexity and geometrical irregularity. However, steel structure projects are still limited by the principal disadvantage of susceptibility to deformation. Therefore, the challenges of the assembly and manufacturing process for steel structures are important. In this paper, to achieve full-loop tracking and control of the assembly and manufacturing process, we propose an integrated approach to undertake the aforementioned challenges via digital twin technology, which combines three modules: (1) deformation detection, (2) pose estimation and optimization, and (3) deformation correction and pose control. This proposed methodology innovatively merges gravitational deformation analysis with geometrical error analysis. Furthermore, the validity of this method’s implementation is demonstrated by the New Shougang Bridge project. The results show that the assembly precision satisfies the standard of less than H/4000, nearing H/6000. Moreover, the elevation difference is less than 20 mm, which satisfies the control precision of the geometric pose. The new method that we propose in this paper provides new ideas for structural deformation control and high-precision assembly, as it realizes dynamic deformation sensing, real-time deviation analysis and manufacturing, and efficient optimization of the assembly process. Full article

Globalization in the field of industry is fostering the need for cognitive production systems. To implement modern concepts that enable tools and systems for such a cognitive production system, several challenges on the shop floor level must first be resolved. This paper discusses the implementation of selected cognitive technologies on a real industrial case-study of a construction machine manufacturer. The partner company works on the concept of mass customization but utilizes manual labour for the high-variety assembly stations or lines. Sensing and guidance devices are used to provide information to the worker and also retrieve and monitor the working, with respecting data privacy policies. Next, a specified process of data contextualization, visual analytics, and causal discovery is used to extract useful information from the retrieved data via sensors. Communications and safety systems are explained further to complete the loop of implementation of cognitive entities on a manual assembly line. This deepened involvement of cognitive technologies are human-centered, rather than automated systems. The explained cognitive technologies enhance human interaction with the processes and ease the production methods. These concepts form a quintessential vision for an effective assembly line. This paper revolutionizes the existing industry 4.0 with an even-intensified human–machine interaction and moving towards cognitivity. Full article

The shape complexity capability of additive manufacturing (AM) is currently the main thrust of the design for AM (DFAM) research. In order to aid designers embracing that complexity-for-free characteristics of AM, many design approaches have been put forth. However, AM does not only benefit parts’ designs: its capability can be harnessed at assembly level to design performant and innovative products. Most of the few contributions on the topic are concerned with part consolidation of existing assemblies, but other advantages such as assembly-free mechanisms, multi-material components, or even component embedding can also improve product design complexity. This paper aims to put forth a thorough DFAM framework for new product development (made of multiple parts) and which consider all the assembly-related characteristics of AM. It considers what can be called AM-based architecture minimization, which includes, among others, part consolidation and assembly-free mechanisms as well. Within context of an ‘AM-factory’, in which the most appropriate machine(s) is/are selected for easing a whole assembly manufacturing before the detailed geometric definition is committed. For the sake of completeness, a methodology based on functional flows has also been investigated for the parts’ design. A gripper as case study has been introduced to illustrate the framework. Full article

Mathematical modeling and data-driven methodologies are frequently required to optimize industrial processes in the context of Cyber-Physical Systems (CPS). This paper introduces the PipeGraph software library, an open-source python toolbox for easing the creation of machine learning models by using Directed Acyclic Graph (DAG)-like implementations that can be used for CPS. scikit-learn’s Pipeline is a very useful tool to bind a sequence of transformers and a final estimator in a single unit capable of working itself as an estimator. It sequentially assembles several steps that can be cross-validated together while setting different parameters. Steps encapsulation secures the experiment from data leakage during the training phase. The scientific goal of PipeGraph is to extend the concept of Pipeline by using a graph structure that can handle scikit-learn’s objects in DAG layouts. It allows performing diverse operations, instead of only transformations, following the topological ordering of the steps in the graph; it provides access to all the data generated along the intermediate steps; and it is compatible with GridSearchCV function to tune the hyperparameters of the steps. It is also not limited to $(X,y)$ entries. Moreover, it has been proposed as part of the scikit-learn-contrib supported project, and is fully compatible with scikit-learn. Documentation and unitary tests are publicly available together with the source code. Two case studies are analyzed in which PipeGraph proves to be essential in improving CPS modeling and optimization: the first is about the optimization of a heat exchange management system, and the second deals with the detection of anomalies in manufacturing processes. Full article