Manufacturing Solutions Research Articles

A novel optimization approach for bio-design of therapeutic compression stockings with pressure fit

For physical-based compression therapeutic modalities, especially compression stockings (CSs), their pressure performances are necessarily evaluated by the standardized cylinder leg mannequins before biological applications. However, the insufficient pressure supply caused by morphological shape diversities between circular leg mannequins and irregular bio-bodies limits the clinical effectiveness and user compliance of CSs. Therefore, an operable and efficiency approach for optimization bio-design and digital development of CSs with enhanced compression performances needs to be proposed. The present study has adopted three-dimensional (3D) body scanning and reverse engineering technologies for lower limb cross-sectional geometric characterization and morphological classification. The irregularity of biological leg circumferential slices was determined and clustered as four levels relating to individual curvature variations. Sequentially, a new pressure prediction model was constructed through characterized geometric variations for bio-based bodies, then its acceptability was validated with good agreement by wearing trials (mean prediction accuracy was 2.53 ± 0.52 mmHg). Thus, the digital pressure reshaped development guidance was obtained based on the classified irregular levels and established pressure prediction models. Consequently, this study provides a novel reliable optimization bio-design solution for manufacturing of therapeutic compression textiles and facilitates the medical efficacy and precision of compression therapy in practical use.

Near‐Nozzle Mixing for Additive Manufacturing of Cementitious Mortar: A Homogeneity Study

AbstractThis paper investigates the Near‐nozzle Mixing (NNM) technique for 3D printing cementitious mortar, focusing on achieving continuous and homogeneous material properties. The NNM's ability to print Natural Sand Mortar (NSM), Recycled Aggregate Mortar (RAM), and Lightweight Mortar (LWM) was assessed. Fresh and hardened properties of each mortar were examined, emphasizing standard deviation (STD) and coefficient of variation (CV) to measure material homogeneity. Fresh properties included slump flow, yield stress, air void volume, density, and water‐to‐cement ratio, while hardened properties covered compressive strength, flexural strength, hardened density, and thermal conductivity. Results showed low CV values for all mortar types, indicating high consistency and homogeneity. NNM showed is capability to print of various materials with customized properties. NSM showed the highest compressive strength, RAM balanced strength and sustainability, and LWM provided the best thermal insulation. The study highlights NNM's versatility and potential for construction applications requiring tailored properties, proving it a promising additive manufacturing solution. The research serves as a foundation for future studies on graded multi‐material printing.

Off the Grid: A new strategy for material-jet 3D printing with enhanced sub-droplet resolution

Drop-on-Demand additive manufacturing could offer a facile solution for scalable on-site manufacturing. With an increasing number of functional materials available for this technology, there are growing opportunities for applications, such as electronics. Here we report on a novel printing strategy, Off-the-Grid (OtG), which enables refined positioning of individual droplets and enhanced resolution compared to the traditional printing strategy. We demonstrate successful printing of structures with feature position control smaller than a single droplet size, and hence enhanced shape fidelity for intricate designs. This strategy is extended to filled patterns, enabling improved layer coverage and customisable inter-layer droplet positioning to control surface morphology. The OtG strategy is applied to produce functional designs, such as conformable circuitry and miniaturized antennae, and is transferable to different materials, from metal nanoparticle and polymeric inks on inkjet platforms, to molten metals on a MetalJet printer. These results could advance exploitation of AM in electronics, wearable electronics, medical devices, and metamaterials.

Experimental investigation of 3D printed infill structures for crash absorbing applications

In recent years additive manufacturing technologies have rapidly evolved and are now an effective tool adopted for final components production. 3D printing techniques allow to realize complex geometries that are difficult if not impossible to fabricate by means of conventional production methods. This peculiarity can be exploited to design and manufacture infill structures that can be used in various engineering applications. Combining lightweight 3D printed infill structures with conventional laminate carbon-epoxy composites can be an efficient way to realize light and stiff components that find their optimal use in crash absorbing applications. Plain polymers and fiber reinforced polymers composites represent an interesting solution for additive manufacturing, offering light weight and ductility of the polymeric matrix with the possible enhancement of mechanical properties with the addition of fibers. This work focuses on the study of commercially available 3D printed infill structures via compression tests on cubic samples, deepening understanding about different densities and different strain rates effects on material’s behavior.

A Model for Probiotic Fermented Food Production

The past few decades have demonstrated how important the human gut microbiota is for human health. Because of this, the use of microbiota-modulating dietary interventions such as probiotics and prebiotics is growing in popularity amongst consumers, food manufacturers, healthcare professionals, and regulators. In particular, there is interest in making a wider variety of foods with probiotic properties. However, as a solution for food manufacturers to produce fermented foods compatible with the “probiotic foods” label definition, we used an impedometric analysis to identify the survival and growth capacity of microbial strains in specific environmental contexts. Using this approach, manufacturers can more effectively select the strains with the highest growth rate for use in probiotic fermented food production trials. To provide a proof of concept, we tested three Lacticaseibacillus rhamnosus probiotic strains growing in milk at different temperatures. We quantified the probiotic’s growth using species-specific primers and quantitative real-time PCR. Overall, our results demonstrate the feasibility of this type of model in facilitating the production of probiotic fermented foods by allowing manufacturers to select strains able to grow under specific conditions. Our model can be used to develop, increase, and target the beneficial health properties of a multitude of fermented foods produced worldwide.

A Survey on Social Manufacturing: A Paradigm Shift for Smart Prosumers

The intelligent manufacturing is a complex engineering system, and the cyber–physical systems (CPSs) and the industrial Internet are the preliminary infrastructures. When cyber–physical–social systems (CPSSs) are formed by extending CPS into the social aspect, Societies 5.0 era is coming. In the Societies 5.0 era, social manufacturing (SM) is an innovative manufacturing solution for intelligent manufacturing. In this article, a survey on SM is introduced. It includes the definition and theory of SM, and comparison between SM and other manufacturing paradigms. Moreover, the key supporting technologies are presented, which can be used to realize SM, such as blockchain, 3-D printing, and big data. Then, the applications of SM to industries are illustrated. The SM has broad application prospects in the high-end customized, distributed manufacturing, and other intelligent manufacturing. Finally, the challenges and future trends are discussed.

Shock Isolation of Light Vehicle Suspension by Modified Eye Leaf Spring

Background: Rickshaws are a popular and inexpensive mode of transportation in Bangladesh for short-distance travel. However, the eye leaf spring in a typical rickshaw suspension system does not provide adequate shock isolation. The coil spring-damper suspension system is more effective, but is costly and not affordable for most manufacturers. Thus, the goal is to modify the eye leaf spring to be inexpensive but a safe and comfortable suspension. Aim: The study aimed to modify the material and structure of the leaf spring to limit the stiffness and the shock energy within a certain range suitable for the rickshaw’s suspension. The focus of the study was on modifying the spring structure, which could be cost-effective. Methods: In this study, flexible bolted joints and EVA sheets have been used to change the spring structure. The study compared the performance of the modified spring with the typical eye leaf spring. Results: The modified eye leaf spring provided improved shock isolation and a more comfortable ride compared to the typical eye leaf spring. The changes made to the spring, such as the use of flexible bolted joints and EVA sheets, limited the stiffness and shock energy within a certain range suitable for the rickshaw’s suspension. The modified spring was also found to be cost-effective. Conclusion: The study has demonstrated the feasibility of using a modified eye leaf spring for light vehicle suspensions, specifically for rickshaws. The modifications made to the spring structure, such as using flexible bolted joints and EVA sheets, provided improved shock isolation, a more comfortable ride, and cost-effectiveness. The modified spring offers an inexpensive solution for manufacturers to produce rickshaws with a safer and more comfortable suspension system.

Can industry 5.0 technologies overcome supply chain disruptions?—a perspective study on pandemics, war, and climate change issues

AbstractIndustry 5.0 (I5.0) is the next industrial revolution that will leverage human intervention in collaboration with intelligent, logical, and smart machines to attain even more user-preferred and resource-efficient manufacturing and supply chain solutions. The main aim of this article is to study I5.0 technologies in supply chains when these are affected by disruptive phenomena such as those created by wars, climate change or pandemics. A systematic literature review methodology was conducted to understand the present knowledge connected with this theme. This study summarises 194 research articles from the period 2009 to 2022 to understand the present knowledge connected with this theme. The research findings show a significant gap related to the adoption of I5.0 technologies to prevent or overcome supply chain disruptions. 194 articles, including journal and review articles, were identified in the literature. The study provides a novel and insightful concept related to I5.0 within the context of supply chain disruptions. The potential applications of I5.0 and Industry 4.0 are elaborately discussed in three areas, namely: (1) disruptions in supply chains due to pandemics; (2) disruptions in supply chains due to war; and (3) disruptions in supply chains due to climate change. Finally, this study highlights research implications and proposes future research avenues that will contribute to further exploring the adoption of I5.0 technologies to prevent, manage and overcome disruptions in supply chains.

CAD-Based Robot Programming Solution for Wire Harness Manufacturing in Aeronautic Sector

Wire harness manufacturing in the aeronautic sector is highly manual work, with production defined by multiple references and small batches. Although complete automation of the production process is not feasible, a robot-assisted approach could increase the efficiency of the existing production means. This paper presents a novel dual-arm robotic solution for workbench configuration and cable routing during the initial steps of wire harness manufacturing. Based on the CAD information of the wire harness, the proposed framework generates trajectories in real-time to complete the initial manufacturing tasks, dividing automatically the whole job between both robots. The presented approach has been validated in a production environment using different wire harness references, obtaining promising results and metrics.

Automated production of gene-modified chimeric antigen receptor T cells using the Cocoon Platform

Autologous cell-based therapeutics have gained increasing attention in recent years because of their efficacy at treating diseases with limited therapeutic options. Chimeric antigen receptor (CAR) T-cell therapy has demonstrated clinical success in hematologic oncology indications, providing critically ill patients with a potentially curative therapy. Although engineered cell therapies such as CAR T cells provide new options for patients with unmet needs, the high cost and complexity of manufacturing may hinder clinical and commercial translation. The Cocoon Platform (Lonza, Basel, Switzerland) addresses many challenges, such as high labor demand, process consistency, contamination risks and scalability, by enabling efficient, functionally closed and automated production, whether at clinical or commercial scale. This platform is customizable and easy to use and requires minimal operator interaction, thereby decreasing process variability. We present two processes that demonstrate the Cocoon Platform's capabilities. We employed different T-cell activation methods—OKT3 and CD3/CD28 Dynabeads (Thermo Fisher Scientific, Waltham, MA, USA)—to generate final cellular products that meet the critical quality attributes of a clinical autologous CAR T-cell product. This study demonstrates a manufacturing solution for addressing challenges with manual methods of production and facilitating the scale-up of autologous cell therapy.

A new integrated strategy for optimising the maintenance cost of complex systems using reliability importance measures

ABSTRACT With the aging of production systems, failure modes become more common resulting in additional maintenance costs. To reduce these costs excess, flexible and smart maintenance strategies should be considered. This article proposes an integrated condition-based maintenance method associating opportunistic and importance measure concepts (IMC). The objective of an IMC-based model is to determine the contribution of the system’s components according to their criticality degree for reliability improvement and maintenance planning. The identification of the best maintenance planning consists of determining the expected minimal cost that guarantees the repair actions of a group of critical components in one shot. Therefore, determining IMC values is not so easy for complex systems, it requires knowing their operational structure, the determination of the reliability value of each configuration and finally calculating each component's IMC degree and ranking them for the prioritisation selection. For testing the proposed method, an industrial case study has been used, regarding a complex system whose components fail at random times. The system undergoes minimal repairs if one or more components fail accidentally or by decision after inspection actions. The numerical results show that the developed approach incurs minimal maintenance costs, and can be integrated as a decision-aid solution for manufacturers.

Knowledge Sharing and Lean Manufacturing in Companies: An Empirical Investigation

Manufacturing companies seeking to be competitive in the market must, in particular, accomplish time saving through precisely planned production processes. One of the main routes to reaching higher production efficiency is Lean Manufacturing (LM) by way of the methods and tools that it brings. However, the key to successful implementation of LM is the employees’ approach to knowledge sharing, an essential component for continuous improvement. This paper is an empirical study whose purpose is to answer the following question: Is knowledge sharing more widely adopted (and if so, how exactly) by companies who have implemented Lean Manufacturing, compared to those who have not?As a result of literature studies, six types of knowledge sharing were identified, related to the way knowledge is shared (formal and informal knowledge sharing), knowledge sharing strategies (codification and personalization strategies) and the scope of knowledge that the company focuses on in its core business (broad and deep knowledge).The relation between the use of LM and knowledge sharing types was examined based on a questionnaire survey conducted among 219 small, medium and large manufacturing enterprises operating in North-West Poland. The data analysis was performed using the ANOVA and post hoc tests.The results demonstrated a significant correlation between the companies’ use of the Lean Manufacturing concept and certain types of knowledge sharing. In particular, it was observed that, compared to the other companies, the companies showing wider use of LM practiced formal ways of knowledge sharing, used the knowledge codification strategy, and were more focused on development and dissemination of broad rather than specialized knowledge. The results also demonstrated that the knowledge sharing approach adopted by the companies was largely determined by other approaches and management methods. It also means that the processes related to knowledge sharing are components of Lean Manufacturing solutions applied in practice.

M. Holland Company offers Mfinity™ line of sustainable resins

On September 12, M. Holland Company, an international distributor of thermoplastic resins and ancillary materials, announced Mfinity™, a proprietary brand of compounds containing up to 100% recycled content in commodity and engineering materials. The new brand is intended as a practical solution for clients, brand owners and original equipment manufacturers (OEMs) looking for custom solutions to help meet their sustainability goals.

Framing School Governance and Teacher Professional Development Using Global Standardized School Assessments

The OECD’s education agenda has been marked since the 1990s by monitoring quality and manufacturing problems and solutions for the so-called knowledge economy. Among the instruments used by the OECD is “PISA for Schools” (Pisa-S), an assessment applied directly to schools worldwide since 2011. In Portugal, it was implemented in 2019 under the designation of “PISA for schools in the municipalities” (PISA-M), claiming to create opportunities for collaborative work between schools to promote the success of local educational policies and the quality of student learning. Taking PISA-M as a policy instrument and building on Coburn problem-framing typology, in this article, the revision of PISA-S to PISA-M is reread to analyze the regulatory rationale for the educational system that PISA-M encodes. This research draws on data from OECD PISA/PISA-S/PISA-M websites and two public hearings with the Portuguese PISA-M coordination in the Portuguese parliament and with education unionists, and in existing research relating to PISA-S. Overall, PISA-M appears to be an instrument to reframe local school governance and teacher professional development practices by capturing problematizations and solutions raised on education, teachers’ development, and how school education should be ordered and coordinated at a municipal scale.

Design thinking-driven development of a modular X-Band antenna using multi-material 3D printing

This study presents the development of a modular parasitic patch antenna using 3D printing and the Design Thinking (DT) methodology. The antenna structure, manufactured with insulating polycarbonate and conductive silver lines, incorporates a reflector, main antenna, and parasitic patch. The study demonstrates the successful application of DT and Design for Manufacture and Assembly (DfMA) principles in optimizing manufacturing efficiency and assembly effectiveness. Simulations and measurements confirm the satisfactory performance of the 3D printed antenna, with a minimum reflection coefficient of -15 dB, efficiency reaching up to 75%, and gain falling within the range of conventionally fabricated antennas. The integration of insulator and conductor materials in 3D printing facilitates the manufacturing of complex structures, while the modular design enables easy installation and customization. This research contributes to the advancement of 3D printing technology for microwave applications, offering cost-effective and efficient manufacturing solutions for industrial antenna production.

Recent Progress in Hybrid Additive Manufacturing of Metallic Materials

Additive Manufacturing (AM) is an advanced technology that has been primarily driven by the demand for production efficiency, minimized energy consumption, and reduced carbon footprints. This process involves layer-by-layer material deposition based on a Computer-Aided Design (CAD) model. Compared to traditional manufacturing methods, AM has enabled the development of complex and topologically functional geometries for various service parts in record time. However, there are limitations to mass production, the building rate, the build size, and the surface quality when using metal additive manufacturing. To overcome these limitations, the combination of additive manufacturing with traditional techniques such as milling and casting holds the potential to provide novel manufacturing solutions, enabling mass production, improved geometrical features, enhanced accuracy, and damage repair through net-shape construction. This amalgamation is commonly referred to as hybrid manufacturing or multi-material additive manufacturing. This review paper aimed to explore the processes and complexities in hybrid materials, joining techniques, with a focus on maraging steels. The discussion is based on existing literature and focuses on three distinct joining methods: direct joining, gradient path joining, and intermediate section joining. Additionally, current challenges for the development of the ideal heat treatment for hybrid metals are discussed, and future prospects of hybrid additive manufacturing are also covered.

Enhanced high-temperature mechanical properties of laser-arc hybrid additive manufacturing of Al-Zn-Mg-Cu alloy via microstructure control

Recently, rapid and cost-effective additive manufacturing solutions for lightweight aluminum alloys with excellent high-temperature mechanical properties have been increasingly in demand. In this study, we combined laser-arc hybrid additive manufacturing with solution and artificial aging treatments to achieve Al-Zn-Mg-Cu alloy with favorable high-temperature strength via microstructure control. Hydrogen pores became the major defect in the as-deposited and heat-treated specimens. The continuous distribution of eutectics with hard-brittle characteristics at the grain boundaries was destructed following heat treatment. High-density η′ precipitates were uniformly dispersed in the heat-treated Al-Zn-Mg-Cu alloy, whereas appeared coarsened and dissolved at 473 K, owing to the rapid diffusion of Zn and Mg. The average 0.2% yield strength (318 ± 16 MPa) and ultimate tensile strength (362 ± 20 MPa) at 473 K after heat treatment were enhanced by approximately 58% and 51%, respectively, compared to those of the as-deposited specimen. In addition, the η′ precipitates contributed to lattice distortions and strain fields, which prevented dislocation motion and increased slip deformation resistance at high temperatures. The as-deposited specimen exhibited intergranular fracture at 473 K, with cracks preferring to propagate along the aggregated eutectics. However, crack propagation proceeded in the sections with more pores in the heat-treated specimen. Our approach may provide a valid option for achieving aluminum alloys with excellent high-temperature mechanical properties.

Dissimilar linear friction welding of Ni-based superalloys

Linear friction welding is a solid-state, near-net shape manufacturing method for metallic alloys which is characterised by complex deformation and metallurgical actions at the weld interface. However, a lack of understanding of the welding parameter interaction and subsequent welding mechanisms is hindering the joint integrity enhancement of dissimilar linear friction welding. In this study, we investigated the influence of various process parameters on macro/micro-formation, microstructural evolution, and properties to establish optimal welding conditions for the sound linear-friction-welded joint integrity of dissimilar superalloys, IN718, and the powder metallurgy FGH96. Increased oscillation frequency or decreased applied pressure promoted continuous dynamic recrystallisation and grain refinement, although discontinuous dynamic recrystallisation remained dominant. Enhanced dissolution of the strengthening phases (γ′ phase on the FGH96 side and δ phase on the IN718 side) was observed from the thermomechanically affected zone to the interface. The subsequent correlation between the microstructure and mechanical properties indicated that solid–solution strengthening was the dominant mechanism for enhancing interfacial bonding, which was promoted by mutual material deformation on both sides. Accordingly, to achieve synergistic plastic deformation in dissimilar linear friction welding, an optimisation strategy of welding parameter combination was proposed and validated by investigating hot compressive dissimilar Ni-based superalloys. The results of simulations of sub-size workpieces showed that using linear friction welding to manufacture bimetallic bladed disks, from conception to completion, was feasible. The paper offers an integrated solution for the full-scale manufacturing of an IN718/FGH96 blisk using linear friction welding based on microstructure–property interactions and relevant simulations, which can ideally serve as the basis for future bimetallic bladed disk manufacturing.

Direct Ink Writing of Nanocellulose and PEDOT:PSS for Flexible Electronic Patterned and Supercapacitor Papers

AbstractPrinted electronic paper identifies its interest in flexible organic electronics and sustainable and clean energy applications because of its straightforward production method, cost‐effectiveness, and positive environmental impact. However, current limitations include restricted material thickness and the use of supporting substrate for printing. Here, 2D and 3D electronic patterned paper are fabricated from direct ink writing (DIW) nanocellulose and PEDOT:PSS‐based materials using syringe deposition and 3D printing. The conductor patterns are integrated in the bulk of the paper, while non‐conductive sections are used as support to form free‐standing paper. The strong interface between the patterns of electronic patterned paper gives mechanical stability for practical handling. The conductive paper‐based electrode has 202 S cm−1 and is capable of handling electric current up to 0.7 A, which can be used for high‐power devices. Printed supercapacitor papers show high specific energy of 4.05 Wh kg−1, specific power of 4615 W kg−1 at 0.06 A g−1, and capacitance retention above 95% after 2000 cycles. The new design structure of electronic patterned papers presents a solution for additive manufacturing of paper‐based composites for supercapacitors, wearable electronics, or sensors for smart packaging.

Laser–Direct Current arc Hybrid Additive Manufacturing of Cu-Cr-Zr Alloy: Microstructure Evaluation and Mechanical Properties

Recently, there has been a growing requirement for rapid and cost-effective additive manufacturing solutions for copper alloys with favorable mechanical properties. In this research, laser–direct current arc hybrid additive manufacturing (LAHAM) was employed to fabricate Cu-Cr-Zr alloy. By way of multi-scale characterization including SEM, EBSD and TEM, the effect of scanning speed on the microstructure was systematically investigated in detail. Moreover, an evaluation of mechanical properties was carried out. The results indicated that columnar grains grew across layers with the growth direction tending to the center of the molten pool. When the scanning speed increased from 250 mm/min to 350 mm/min, the proportion of high-angle grain boundaries exceeded 69% and reached a maximum of 79% at 300 mm/min. A large amount of Cr phase was precipitated from the Cu matrix. Both submicron and nanoscale Cr precipitates were observed. Statistically, the area proportion of Cr precipitates was up to 26.3% at 300 mm/min. The changes of heat input and remelting effects were the main reasons for the change in the precipitate level. As a result, the mechanical properties of the Cu-Cr-Zr alloy were enhanced via precipitation strengthening. When the scanning speed was 250 mm/min, the Cu-Cr-Zr alloy sample exhibited an ultimate tensile strength of 311.3 ± 7.8 MPa with an elongation of 38.6 ± 5.6%.