Rapid Prototyping Research Articles

Bubble-Free Frontal Polymerization of Acrylates via Redox-Initiated Free Radical Polymerization.

Thermal frontal polymerization (FP) of acrylate monomers mixed with conventional peroxide initiators leads to significant bubble formation at the polymerizing front, limiting their practical applications. Redox initiators present a promising alternative to peroxide initiators, as they prevent the formation of gaseous byproducts during initiator decomposition and lower the front temperature, thereby enabling bubble-free FP. In this study, we investigate the FP of acrylate monomers of varying functionalities, including methyl methacrylate (MMA), 1,6-hexanediol diacrylate (HDDA), and trimethylolpropane triacrylate (TMPTA), using N,N-dimethylaniline/benzoyl peroxide (DMA/BPO) redox couple at room temperature and compare their front behavior, pot life, and bubble formation with those of same resin systems mixed with a conventional peroxide initiator, Luperox 231. The use of redox couples in FP of acrylates shows promise for rapid, energy-efficient manufacturing of polyacrylates and can enable new applications such as 3D printing and composite manufacturing.

Prototype for Multi-UAV Monitoring–Control System Using WebRTC

Most unmanned aerial vehicle (UAV) ground control station (GCS) solutions today are either web-based or native applications, primarily designed to support a single UAV. In this paper, our research aims to provide an open, universal framework intended for rapid prototyping, addressing these objectives by developing a Web Real-Time Communication (WebRTC)-based multi-UAV monitoring and control system for applications such as automated power line inspection (APOLI). The APOLI project focuses on identifying damage and faults in power line insulators through real-time image processing, video streaming, and flight data monitoring. The implementation is divided into three main parts. First, we configure UAVs for hardware-accelerated streaming using the GStreamer framework on the NVIDIA Jetson Nano companion board. Second, we develop the server-side application to receive hardware-encoded video feeds from the UAVs by utilizing a WebRTC media server. Lastly, we develop a web application that facilitates communication between clients and the server, allowing users with different authorization levels to access video feeds and control the UAVs. The system supports three user types: pilot/admin, inspector, and customer. Our research aims to leverage the WebRTC media server framework to develop a web-based GCS solution capable of managing multiple UAVs with low latency. The proposed solution enables real-time video streaming and flight data collection from multiple UAVs to a server, which is displayed in a web application interface hosted on the GCS. This approach ensures efficient inspection for applications like APOLI while prioritizing UAV safety during critical scenarios. Another advantage of the solution is its integration compatibility with platforms such as cloud services and native applications, as well as the modularity of the plugin-based architecture offered by the Janus WebRTC server for future development.

Development of ANN model for predicting mechanical properties of 3D printed PEEK polymer using FDM and optimization of process parameters for better mechanical properties

Additive manufacturing (AM) has evolved from a proven technology to a rapid prototyping tool with great potential. This technology is widely used in many industries such as automotive, aerospace, and medical; fused deposition modeling (FDM) is a popular 3D printing technique for producing PEEK (polyether ether ketone) parts, including implant prosthetic teeth. In this study, artificial neural network (ANN) modeling, parametric optimization, and experimental examination of PEEK 3D printing were conducted to enhance 3D printing processes. In this study, four critical process factors (infill density, layer height, printing speed, and infill pattern) influence the surface roughness, mechanical strength, and elastic modulus of the printed samples. Utilizing a 4–12–3 network design, this study demonstrates that an ANN model with an average error of less than 5% is optimal for all three responses. Furthermore, the study employed a teaching and learning based optimization algorithm (TLBO) and a non-dominated sorting genetic algorithm (NSGA) to optimize the printing process to obtain improved mechanical properties. The findings highlight TLBO’s ability to minimize surface roughness to 6.01 μm and NSGA’s capability to maximize the elastic modulus to 1253.35 MPa and ultimate tensile strength to 65.55 MPa. Microstructural studies supported the results obtained through parametric analysis and optimization.

Three–dimensional matrices for enhanced coral settlement through design for additive manufacturing

Purpose The effects of climate change have been contributing to coral reef degradation. Artificial reefs are one method being used to counteract this destruction. However, the most common artificial approaches, such as sunken vehicles and prefabricated cement reefs, do not allow adequate coral development. This paper aims to demonstrate how designers, using additive manufacturing and computational design techniques, can create artificial reefs that better mimic natural reef structures. Design/methodology/approach This research focuses on developing three-dimensional matrices through computational design using additive manufacturing to achieve better coral settlement. A “Nature Centered Design” approach was followed, with the corals at the center of the design project. Samples with different geometries and roughness, produced using paste-based extrusion with porcelain and porcelain with oyster shell, were tested in a controlled environment to investigate the settlement preference of soft corals. Findings The rapid prototyping of samples confirmed the preference of corals to settle to complex surfaces compared to smooth surfaces. Porcelain showed comparable results to Portland cement, suggesting further testing potential. A closer resemblance to the natural and intricate forms found in coral reefs was achieved through computational design. Originality/value This paper proposes a new approach combining rapid prototyping with coral’s biological responses to enhance the understanding of their surface settlement preference. The Nature Centered Design approach, with additive manufacturing and computational design, made it possible to create an innovative working model that could be customized depending on the implementation area or intended coral species, validating the design approach as a method to support environmental conservation.

3D printing carbon from aqueous all aromatic polyimides

All-aromatic polyimides serve as versatile precursors for carbon formation due to their high aromatic content and repeating unit planarity, which synergistically enables pyrolysis to ordered carbon. Recent publications disclosed facile synthetic methods for additive manufacturing (3D printing) of all-aromatic polyimides using a pendant salt approach for ultraviolet-assisted direct ink write (DIW) additive manufacturing. This manuscript describes the introduction of pendant sodium sulfonate functionality to the poly(amic acids), and water-soluble all-aromatic polyimide precursors displayed suitable rheological properties for DIW at room temperature and vat photopolymerization (VP) at 50 °C. These aqueous solutions enabled the formation of microporous polyimide structures with a direct freeze-casting method and dense structures with gradual heating under inert atmosphere to 200 °C and subsequent thermal post-processing to 400 °C. Furthermore, polyimide 3D structures function as efficient carbon precursors when pyrolyzed at 2000 °C under inert atmosphere. Raman spectroscopy revealed carbonized 3D structures with characteristic graphitic and disordered carbon bands, which was indicative of polycrystalline, disordered glassy carbon. Furthermore, electrical conductivity measurements suggest opportunities for the formation of 3D conductive structures.

Melting and solution mixing in the production of photocatalytic filaments for 3D printing

3D printing is a fast-growing technology with benefits like rapid prototyping and versatile design capabilities. However, Fused Deposition Modeling (FDM) needs improvement due to limited material options. This study proposes a method for producing photocatalytic prototypes using 3D printing/FDM, focusing on environmental applications like contaminant degradation. Key steps included filament production through melt and solution mixing, defining geometries, 3D printing functional prototypes, and characterizing materials chemically, thermally, microscopically, and mechanically. The photocatalytic capacity was evaluated via tetracycline degradation, showing 45–60% efficiency for ZnO filaments and up to 65% for TiO2 filaments. ZnO-functionalized parts maintained 80% removal capacity after 10 reuse cycles without activation, indicating reduced leaching and photo corrosion. This study advances 3D printing/FDM research for environmental applications, providing a methodology for producing effective photocatalytic prototypes.

Design an RF Up-Down Convertor using Software Defined Radio and GNU Radio

There is a need to design of RF Up/Down- converter for (from C/Ku to/from L band) signals required for several applications. The proposed work presents a design of an RF Up/Down Converter that makes use of GNU Radio and Software-Defined Radios (SDRs). The converter helps in frequency translation between the C/Ku and L bands, leading to a cost-effective and versatile solution for RF signal processing. By using open-source GNU Radio software, the proposed system enhances accessibility, enabling its deployment in diverse applications, from satellite communication to radar systems. The converter’s unique features include real-time processing capabilities, customization through an intuitive graphical interface, and Python scripting. This idea presents the design considerations, signal processing techniques, and performance evaluation of the RF Up/Down Converter. The advantages of an open-source solution over other available alternatives are in terms of cost, flexibility, and rapid prototyping. Simulation and hardware results demonstrate the efficacy of the proposed work.

Rapid Prototyping as a Low-Cost Push Factor to Promote the Adoption of IoT Technology in the Healthcare: A Case Study

Rapid Prototyping as a Low-Cost Push Factor to Promote the Adoption of IoT Technology in the Healthcare: A Case Study

Characterisation and manufacturing methods of material extrusion 3D printing composite filaments based on polylactide and nanohydroxyapatite

As the pace of scientific research and technological advancement accelerates, there is an increasing demand for rapid on-site prototyping with specific materials. Additive manufacturing through material extrusion 3D printing has emerged as an economically viable solution to this need. The production of custom filaments for this process frequently depends on low-volume filament manufacturing lines. A significant challenge in such production processes is maintaining the quality of the filament throughout its entire length, as this has a considerable impact on the quality of the final printed object. To ensure consistent quality, it is essential to monitor and manage a range of essential properties, including diameter consistency, material homogeneity and compound ratio. This study presents the implementation of a real-time filament quality monitor (R-FQM), which provides detailed insight into the longitudinal characteristics of the filament during the manufacturing process and its crystallinity analysis. In conjunction with a new proof-of-concept drawing process for reducing filament diameter by multi stage drawing die solid-state extrusion, this approach addresses the challenge of maintaining filaments quality. Several PLA-based filaments were produced for research purposes: pure PLA and composites containing 5 and 10wt% nanohydroxyapatite. Produced composite filaments had significantly greater diameter variation compared to pure PLA (largest for 5% filler ± 0.29mm). The diameter of the resulting filaments was reduced in the range of 2.5-1.4mm using the SSE approach. In addition to the R-FQM method, the filaments were characterised by structural, thermal and mechanical property analysis. The analyses showed that the 10% hydroxyapatite content in the filament subjected to the SSE process can lead to significant weakening of the material. However, all the filaments were suitable for 3D printing for biomedical applications. The research carried out demonstrated the complementarity of the R-FQM method with classical methods, confirming the effectiveness of the approach described.

A 3D printing-based hybrid manufacturing method for high-strength polymeric medical implant fabrication

This paper presents a novel 3D printing-based hybrid manufacturing method to fabricate high-strength polymeric medical implants. Poly-ether-ether-ketone (PEEK) and polyether sulfone (PES) are blended to make filament for use with the fused filament fabrication technique to print custom designed implants. After printing and annealing, PES is removed by leaching to create interconnected porous PEEK structure with suitable pore size and porosity for bone tissue ingrowth. The proposed method provides a versatile approach to fabricating medical implants that are both mechanically strong and microstructurally inducive to osseointegration. The polymeric implants are also X-ray transparent to allow post-surgery evaluations using an imaging method. An intervertebral spacer implant example is used to demonstrate the proposed fabrication method.

Material selection and design of intake blades for aircraft engines based on additive manufacturing

Abstract The intake blades of aircraft engines are mainly used to capture and guide external air into the engine and are the foundation of engine operation. Their materials and design are related to the performance level and reliability of the entire engine. The “additive” 3D printing manufacturing method has the advantages of high precision, low cost, less material waste, strong design, and a short research and development cycle. This article proposes the use of GH4169 high-temperature alloy as the 3D printing material for the service requirements of aircraft engine intake blades, constructs a 3D printing model, and designs and realizes the 3D printing of engine intake blades.

Influence of Printing Parameters to optimize mechanical properties in additive manufacturing – A Review

Abstract Additive manufacturing (3D printing) is a revolutionary technology with widespread applications among various industries. It is a cost effective and fast prototyping technology of 20th century, the parts produced by 3D printing are not only used for pre-production samples but also for replacement of functional parts in various applications. Various methods of 3D printing technologies viz., Fused Deposition, Resin printing etc., are available, however Fused Deposition Modelling (FDM) technique is very popular since it is promising and cost effective. There are two major aspects needs to be considered in preparing a sample from 3D printing, i.e., selection of material and printing parameter. With the advancement of material technology from time to time, the efficient and quality products that are produced with this technology. The present study explores the impact of various parameters that affect mechanical properties of 3D printed Polylactic Acid (PLA) in horizontal orientation.

A Practical Guide to 3D Printing for Chemistry and Biology Laboratories.

Three-dimensional (3D) printing promises a revolution in laboratory creativity by enabling rapid prototyping, broader availability of scientific apparatuses, and transformative scientific workflows. We believe all chemistry and biology laboratories should equip themselves with one or more 3D printers and a critical mass of scientists trained to operate them. This overview surveys the techniques, intricacies, and pitfalls associated with 3D printing of functional parts, including measurements, computer-aided design, slicing, limitations of 3D printing, troubleshooting, tips for tricky filaments, and 3D printer maintenance. A flow cells are essential tools in chemistry and biology laboratories, we discuss techniques relevant to the construction of watertight 3D-printed parts. Finally, we articulate a set of principles required for reporting 3D-printed innovations to improve the field's reproducibility and encourage iterative improvements by other scientists. Ideally, authors, peer reviewers, and editors will adopt these principles. We hope these protocols inspire a new generation of publications applying 3D printing in chemistry and biology-especially highly reproducible inventions with the requisite detail and associated documentation. Such reports will facilitate broad adoption and creative iteration of the most innovative designs, thus accelerating discovery in chemistry and biology. © 2024 The Author(s). Current Protocols published by Wiley Periodicals LLC.

Direct electrodeposition on conductive polymer structures for microwave device manufacturing

This work introduces a method that merges Additive Manufacturing (AM) with Direct Electrodeposition to efficiently produce microwave (MW) components. Using material extrusion (MEX) with conductive polymers and an improved direct copper deposition approach, this method streamlines the manufacturing process, bypassing the need for intermediate conductive layers. By minimizing the distance electrical currents travel within the conductive polymer, we obtain homogeneous copper deposits directly on the polymer with low roughness and excellent adhesion. The practical application of our technique is showcased through the radiative performance evaluation of a millimeter wave horn antenna manufactured using our approach, demonstrating similar electromagnetic performances with respect to a commercially available reference. The method proposed in this paper results in lightweight, material-efficient components with increased design flexibility, opening up possibilities for rapid prototyping and fabrication of new MW devices.

Nature-inspired approach for enhancing the fracture performance of 3D printed strain-hardening cementitious composites (3DP-SHCC)

3D printing technology enhances design flexibility, enables the creation of complex geometrical structures, facilitates rapid prototyping, and allows the fabrication of micro- and macroscopic structures. This study investigates the use of 3D concrete printing to create Bouligand structures inspired by mantis shrimp. Bouligand-printed strain-hardening cementitious composites (SHCC) with different pitch angles (15°, 30°, 45°, 60°, 75°, and 90°) are fabricated and compared with traditional parallel-printed and mold-cast SHCC. The fracture behavior of these specimens is investigated through three-point bending tests on notched beams. The results reveal that Bouligand-printed specimens exhibit enhanced flexural strength, fracture energy, and fracture toughness, ranging from 0.97 to 1.29 times, 0.99 to 1.63 times and 0.87 to 1.47 times that of the mold-cast specimens, respectively. Bouligand-printed specimens with a pitch angle of 30° exhibits the highest flexural strength, fracture energy, and fracture toughness. The Bouligand-printed SHCC enhance toughness through the synergistic effects of crack twisting and bridging. A finite element model integrating cohesive elements with the concrete plastic damage model is developed to numerically replicate the experimental process. This study highlights the potential of 3D concrete printing for the fabrication of biomimetic concrete structures with superior fracture performance.

An investigation of prototype development using 3D printer: A digital fabrication approach

Abstract Additive manufacturing (AM) is a widely used technique in several industries for rapid prototyping and layer-by-layer fabrication of a new product. The influence of printer settings and print quality is essential for the performance of products in a variety of applications. The popularity of manufacturing using 3D printing is growing rapidly. In view of this, an investigation is carried out on the 3D printing techniques, their applications, and prototype materials for complex mechanical parts such as an impeller. The present study thoroughly considers the fundamental techniques in 3D printing technology, materials, and recent advancements applied to the current application and accepted trends. The 3D printing technology is advantageous as it accepts a wide range of designs, allows customized manufacturing, minimizes waste, builds intricate structures, and creates prototypes rapidly. Layer height of 0.2 mm, speed of 90 mm/s, and infill density of 80% were determined as the optimal print settings considering time, material cost, and properties. Considering the flexural qualities, the optimized values of layer height, print speed, and infill density were 0.15 mm, 70 mm/s, and 50%, respectively. It was observed that the uniform elongation (UEL) and ultimate stress (UTS) of a component increase as the layer thickness increases for the considered layers.

Fourier Surfaces Reaching Full-Color Diffraction Limits.

Optical Fourier surfaces (OFSs), characterized by sinusoidally profiled diffractive optical elements, can outperform traditional binary-type counterparts by minimizing optical noise through selectively driving diffraction at desired frequencies. While scanning probe lithography (SPL), gray-scale electron beam lithography (EBL), and holographic inscriptions are effective for fabricating OFSs, achieving full-color diffractions at fundamental efficiency limits is challenging. Here, an integrated manufacturing process is presented, validated theoretically and experimentally, for fully transparent OFSs reaching the fundamental limit of diffraction efficiency. Leveraging holographic inscriptions and soft nanoimprinting, this approach effectively addresses challenges in conventional OFS manufacturing, enabling scalable production of noise-free and maximally efficient OFSs with record-high throughput (1010-1012 µm2h-1), surpassing SPL and EBL by 1010 times. Toward this end, a wafer-scale OFSs array is demonstrated consisting of full-color diffractive gratings, color graphics, and microlenses by the one-step nanoimprinting, which is readily compatible with rapid prototyping of OFSs even on curved panels, demanding for transformative optical devices such as augmented and virtual reality displays.

The Effect of Gastric Acid and Material Type on the Surface Roughness of Additive and Subtractive Manufacturing Resins.

The aim of this study is to examine the effect of gastric acid on the surface roughness of additive and subtractive manufacturing resin. In this study, two subtractive manufacturing CAD-CAM resin nanoceramic (CerasmartTM270 (CS), LavaTM Ultimate (LU)) and two additive manufacturing 3D printing permanent resin (VarseoSmile Crownplus (VSP), Crowntec (CT)) was used. CS and LU samples were turned into 10 mm diameter cylinders with a scraper and cut into 2 mm slices on the cutting device. CT and VSP samples were produced on a 3D printer (2mm thickness-10mm diameter) (n:15). All samples were exposed to a cycle of 60 seconds of gastric acid, 5 seconds of distilled water, and 30 minutes of artificial saliva, 6 times a day for 10 days. Surface roughness mean (Ra) and depth (Rz) was measured with a contact profilometer at baseline and after gastric acid cycling. Data were analyzed using SPSS (22.0), One way ANOVA, post-hoc Tukey's and Independent-t test (p <.05). Ra-Rz values of CT and VSP were significantly higher than CS and LU at baseline and after the gastric acid cycle (p <.05). After the gastric acid cycle, the Ra-Rz values of all materials increased significantly compared to the baseline (p <.05) but the Ra values of all materials were at a clinically acceptable level (<0.2µm). Although additive manufacturing 3D printing permanent resins offered higher roughness values, they weren't at a clinically unacceptable level. Therefore, they can be an alternative to subtractive manufacturing CAD-CAM resin nanoceramics.

Rapid Prototyping Technology: A Driving Force in Product Design Innovation

Abstract: This paper explores the transformative impact of rapid prototyping on product design processes across various industries. Rapid prototyping, characterized by its ability to quickly create physical models from digital designs, significantly enhances the iterative design phase, facilitating early testing and validation of concepts. RP includes the integration of technologies such as 3D printing, computer-aided design (CAD), and additive manufacturing in accelerating product iterations, reducing time-to-market, and fostering innovation. Rapid prototyping (RP) has emerged as a transformative approach in product development, significantly enhancing design processes across various industries. Sectors including automotive, consumer electronics and healthcare show how rapid prototyping streamlines communication among stakeholders, enhances user feedback incorporation, and reduces production costs

Framework for developing entrepreneurial business models: Theory and practical application

A framework for developing entrepreneurial business models is crucial for guiding entrepreneurs from conceptualization to practical application in a dynamic market environment. This review outlines a comprehensive framework that integrates theoretical concepts with practical approaches to help entrepreneurs create robust and adaptable business models. The framework is grounded in a synthesis of contemporary entrepreneurship theories and practical insights drawn from case studies of successful ventures. It begins with a theoretical exploration of foundational business model components, including value proposition, customer segments, revenue streams, and cost structures. By leveraging established models such as the Business Model Canvas and the Lean Startup methodology, the framework provides a structured approach for entrepreneurs to design and validate their business models. A key component of the framework is its emphasis on iterative development and validation. Entrepreneurs are encouraged to employ lean principles, such as rapid prototyping and customer feedback loops, to refine their business models. This iterative process helps in adapting to market changes and customer needs, reducing risk, and improving the likelihood of success. The framework also incorporates strategic analysis tools to evaluate market opportunities, competitive landscape, and potential challenges. Practical application is emphasized through detailed guidelines and tools for each stage of business model development. This includes methodologies for conducting market research, identifying key resources and partnerships, and establishing operational processes. Additionally, the framework addresses the importance of financial planning and risk management, offering practical advice on funding strategies and contingency planning. The paper also highlights the significance of contextual factors, such as industry trends, regulatory environment, and technological advancements, in shaping business models. By incorporating these elements, the framework provides a holistic approach to entrepreneurial business model development. In conclusion, the proposed framework serves as a valuable guide for entrepreneurs seeking to develop and implement effective business models. It combines theoretical insights with practical tools and strategies, enabling entrepreneurs to navigate the complexities of the business landscape and achieve sustainable success. This approach not only enhances the strategic planning process but also fosters innovation and adaptability in an ever-evolving market environment.