Rapid Prototyping Applications Research Articles

Enhancing Furniture Manufacturing with 3D Scanning

Product design and manufacturing leverage 3D scanning for various applications. This study aims to investigate the effectiveness of 3D scanning in furniture production by surveying the literature and showcasing four real-world case studies. The literature review reveals that 3D data acquired from real-world objects have applications in research, rapid prototyping, restoration, and preservation of antique furniture, optimizing CNC machining processes, and measuring furniture components for quality control. The case study descriptions demonstrated the circumstances, rationale, and methodology for 3D scanning. All the case studies analyzed stem from the collaboration between the Laboratory for Product Development and Design at the Faculty of Mechanical Engineering at the University of Sarajevo and various furniture production enterprises from Bosnia and Herzegovina. The conclusions highlight that 3D scanning in the furniture sector is advantageous for developing computer-aided design models from early-stage design prototypes, validating the dimensional accuracy of manufactured components by comparing with CAD models, safeguarding and reconstructing vintage furniture, and remanufacturing formerly produced goods that lack complete technical records (reverse engineering).

Improving the Performance of Photoactive Terpene-Based Resin Formulations for Light-Based Additive Manufacturing.

Photocurable liquid formulations have been a key research focus for the preparation of mechanically robust and thermally stable networks. However, the development of renewable resins to replace petroleum-based commodities presents a great challenge in the field. From this perspective, we disclose the design of photoactive resins based on terpenes and itaconic acid, both potentially naturally sourced, to prepare photosets with adjustable thermomechanical properties. Biobased perillyl itaconate (PerIt) was synthesized from renewable perillyl alcohol and itaconic anhydride via a scalable solvent-free method. Photoirradiation of PerIt in the presence of a multiarm thiol and photoinitiator led to the formation of networks over a range of compositions. Addition of nonmodified terpenes (perillyl alcohol, linalool, or limonene) as reactive diluents allowed for more facile preparation of photocured networks. Photosets within a wide range of properties were accessed, and these could be adjusted by varying diluent type and thiol stoichiometry. The resins showed rapid photocuring kinetics and the ability to form either brittle or elastic materials, with Young's modulus and strain at break ranging from 3.6 to 358 MPa and 15 to 367%, respectively, depending on the chemical composition of the resin. Glass transition temperatures (Tg) were influenced by thioether content, with temperatures ranging from 5 to 43 °C, and all photosets displayed good thermal resistance with Td,5% > 190 °C. Selected formulations containing PerIt and limonene demonstrated suitability for additive manufacturing technologies and high-resolution objects were printed via digital light processing (DLP). Overall, this work presents a simple and straightforward route to prepare renewable resins for rapid prototyping applications.

The effect of triglycerol diacrylate on the printability and properties of UV curable, bio-based nanohydroxyapatite composites

3D printable biopolymer nanocomposites composed of hydroxyapatite nanoparticles and functionalized plant-based monomers demonstrate potential as sustainable and structural biomaterials. To increase this potential, their printability and performance must be improved. For extrusion-based 3D printing, such as Direct Ink Writing (DIW), printability is important for print fidelity. In this work, triglycerol diacrylate (TGDA) was added to an acrylated epoxidized soybean oil:polyethylene glycol diacrylate resin to increase hydrogen bonding. Greater hydrogen bonding was hypothesized to improve printability by increasing the ink's shear yield strength, and therefore shape holding after deposition. The effects of this additive on material and mechanical properties were quantified. Increased hydrogen bonding due to TGDA content increased the ink's shear yield stress and viscosity by 916% and 27.6%, respectively. This resulted in improved printability, with best performance at 3 vol% TGDA. This composition achieved an ultimate tensile strength (UTS) of 32.4 ± 2.1 MPa and elastic modulus of 1.15 ± 0.21 GPa. These were increased from the 0 vol% TGDA composite, which had an UTS of 24.8 ± 1.8 MPa and a modulus of 0.88 ± 0.06 GPa. This study demonstrates the development of bio-based additive manufacturing feedstocks for potential uses in sustainable manufacturing, rapid prototyping, and biomaterial applications.

Investigation of the Hydrolytic Degradation Kinetics of 3D-Printed PLA Structures under a Thermally Accelerated Regime.

The application of biobased and biodegradable polymers, such as polylactide (PLA), in fused deposition modeling (FDM) 3D-printing technology creates a new prospect for rapid prototyping and other applications in the context of ecology. The popularity of the FDM method and its significance in material engineering not only creates new prospects for the development of technical sciences on an industrial scale, but also introduces new technologies into households. In this study, the kinetics of the hydrolytic degradation of samples obtained by the FDM method from commercially available PLA filaments under a thermally accelerated regime were analyzed. The investigation was conducted at the microstructural, supramolecular, and molecular levels by using methods such as micro-computed tomography (micro-CT), wide-angle X-ray diffraction (WAXD), viscosimetry, and mass erosion measurements. The obtained results clearly present the rapid structural changes in 3D-printed materials during degradation due to their amorphous initial structure. The complementary studies carried out at different scale levels allowed us to demonstrate the relationship between the observed structural changes in the samples and the hydrolytic decomposition of the polymer chains, which made it possible to scientifically understand the process and expand the knowledge on biodegradation.

PCGen: A Fully Parallelizable Point Cloud Generative Model.

Generative models have the potential to revolutionize 3D extended reality. A primary obstacle is that augmented and virtual reality need real-time computing. Current state-of-the-art point cloud random generation methods are not fast enough for these applications. We introduce a vector-quantized variational autoencoder model (VQVAE) that can synthesize high-quality point clouds in milliseconds. Unlike previous work in VQVAEs, our model offers a compact sample representation suitable for conditional generation and data exploration with potential applications in rapid prototyping. We achieve this result by combining architectural improvements with an innovative approach for probabilistic random generation. First, we rethink current parallel point cloud autoencoder structures, and we propose several solutions to improve robustness, efficiency and reconstruction quality. Notable contributions in the decoder architecture include an innovative computation layer to process the shape semantic information, an attention mechanism that helps the model focus on different areas and a filter to cover possible sampling errors. Secondly, we introduce a parallel sampling strategy for VQVAE models consisting of a double encoding system, where a variational autoencoder learns how to generate the complex discrete distribution of the VQVAE, not only allowing quick inference but also describing the shape with a few global variables. We compare the proposed decoder and our VQVAE model with established and concurrent work, and we prove, one by one, the validity of the single contributions.

SELECTION AND JUSTIFICATION OF THE LOCATION OF CAMERAS OF THE ALLROUND VISION SYSTEM ON AN UNMANNED DUMP TRUCK

The choice of equipment installation location on the sides of an unmanned vehicle, and especially such a dump truck, is a difficult task, which is solved, as a rule, intuitively and by the method of fullscale modeling. The authors of the article have solved the formulated problem, on substantiation of the choice of places of sensorics arrangement on the dump truck, using the developed specialized software application. The Carla simulator was chosen as a tool for carrying out the research as it has wide possibilities of visualization of the surrounding world. At the initial stage of selecting the location of the camera arrangement, the requirements for their viewing angles and the quality of the image obtained from them were formulated. This required the development of a software application in the Python language using the Open3D library, the choice of which is justified by the fact that the Carla simulator provides access to its API through a library for this language, and also because it allows rapid prototyping of applications. The developed software application helps the user to select the location of the video cameras on the dump truck in order to experience the unmanned control system. Further research is aimed at automating the selection of camera locations on board an unmanned dump truck.

Low-cost prototyping of nitinol wires/frames using polymeric cores and sacrificial fixtures with application in individualized frames anchoring through the atrial septum

Self-expanding frames for minimally invasive implants are typically made from nitinol wires and are heat treated to maintain the desired shapes. In the process of heat treatment, nitinol structures are placed in a high-temperature oven, while they are confined by a fixture. During this process, nitinol exerts a high amount of force. Accordingly, a fixture requires high mechanical strength and temperature resistance; this is why fixtures are typically made from metals. The use of metal fixture also increases the turnaround time and cost. However, accelerating this process is beneficial in many applications, such as rapid development of medical implants that are patient-specific. Inspired by the use of sacrificial layers in microfabrication technology, here we propose a novel method for shape setting nitinol wires using a sacrificial metal fixture. In this process, the nitinol wires are first aligned inside copper hypotubes. Next, the forming process is done using hand-held tools to shape complex geometrical structures, annealing the nitinol reinforced by copper, and then selectively etching copper hypotubes in ammonium persulfate solutions. In this process, other sacrificial cores, which are 3D printed or cast from low-cost polymers, are also used. This combination of polymeric cores and minimal use of metals enables reducing the cost and the turnaround time. As a proof of concept, we showed that this process was capable of fabricating springs with mm or sub-mm diameters. The result showed a change of less than 5% in the intended diameter of the nitinol spring with diameters ranging from ~ 0.7 to 1.9 mm, which confirms copper as a suitable sacrificial fixture to obtain the desired complex geometry for nitinol. A metric, based on the elastic strain stored in copper is suggested to predict the possible variation of the intended dimensions in this process. Finally, to demonstrate the potential of this method, as proof of concept, we fabricated NiTi wire frames designed for anchoring through the atrial septum. These frames demonstrated septal defect occluders that were designed based on a patient’s cardiac image available in the public domain. This low-cost rapid fabrication technique is highly beneficial for a variety of applications in engineering and medicine with specific applications in rapid prototyping of medical implants.

Weldability of 316L Parts Produced by Metal Additive Manufacturing

The processes of metal additive manufacturing (AM) are no longer confined to rapid prototyping applications and are seeing increasing use in many fields for the production of tools and finished products. The ability to design parts with practically zero waste, high precision, complex geometry, and on-demand fabrication are among the advantages of this manufacturing approach. One of the drawbacks of this technique is the productivity rate, as the parts are made layer by layer, which also increases the production cost. Moreover, even the working space is limited, especially for the powder bed fusion technique. In view of these disadvantages and in order to guarantee the profitability of this process, it should be oriented to the production of complex components that have a limited volume with a design adapted to additive manufacturing. One solution with which to circumvent these drawbacks is to combine the 3D printing process with conventional manufacturing processes. When designing products, one may choose to use additive manufacturing to create locally complex parts and assemble them with parts produced by conventional processes. On the other hand, and due to the limited AM printing chamber space, it may be necessary to print large parts in multiple smaller parts and then assemble them. In order to investigate the weldability of stainless steel 316L parts produced by laser powder bed fusion (L-PBF), the mechanical behavior of different welding assemblies is tested. Five configurations are studied: non-welded AM specimens, two AM parts welded together, one AM part and one laser cut part welded together, two laser-cut parts welded together, and non-welded laser cut specimens. Welding is performed using the Pulsed Gas Metal Arc Welding process (GMAW-P). Specimen strength is assessed through static and fatigue tests. The results demonstrate that 316L AM parts are weldable, and the tensile and fatigue properties of L-PBF 316L welded components and welded laser cut components are comparable. GMAW-P welding led to lower fatigue results for AM components than for other configurations, but the difference is not important. It was observed that welding defects may have a direct impact on mechanical properties.

Rapid Prototyping and Tooling Technology to Assist the Development of Low-Cost Dies

This case study aims toward the importance of the application of rapid prototyping and tooling technology in die design and manufacturing. Many conventional machining processes of die manufacturing, including computer numeric control (CNC) machining and electric discharge machining (EDM), are used by the local manufacturers of die, but these processes are time-consuming and expensive. There is a need to explore opportunities to reduce die manufacturing costs. This paper aims to assist the development of low-cost dies through the application of rapid prototyping and tooling technology. For this purpose, solid works software was used to design the die of a 4-hole Lego Block. 3D printing was incorporated in the existing capability of investment casting process for die manufacturing. A proper gating system design consideration was taken into account to ensure the accurate flow of casting material for achieving fine surface finish. From the results, it has been observed that gating system design with four ingates gives the optimum value of surface finish (~3.4156μm). The proposed rapid prototyping and tooling technology makes the practitioners (tool makers) capable of making dies with complex shapes, superior surface finishes, and dimensional accuracy in less or no time.

The role of additive manufacturing in the investment casting process

The aim of this study was to systematically describe the additive manufacturing (AM) technologies used for various casting technologies and how rapid investment casting (RIC) is changing the field of casting. The capability and effectiveness of additive manufacturing to provide investment casting production solutions has been investigated. The traditional investment casting method is less efficient in terms of cost and time to develop new wax models of solid tooling for low volume production or prototypes. To overcome this problem, it is proposed to introduce additive manufacturing to these processes to produce investment casting models. This paper discusses specific applications of rapid prototyping in this area. The study concluded that the use of additive manufacturing for investment casting instead of the traditional method is more cost- and time-efficient. Terms and designations: RP – Rapid Prototyping, IC, RIC –(Rapid) Investment Casting, PM – Project Manager, AT – Additive technologies, AM – Additive manufacturing

Mitigation of Design Issues in Development of Anatomical Models Using Rapid Prototyping

Literature indicates rapid prototyping (RP) application has become more widespread in design and development of human anatomy models. Practitioners are facing challenges in deployment of RP tools for development of cost-effective medical models, because there are no proven decision support systems in the selection of parameters such as speed, accuracy, materials, and customisation of commercial software. This study aims at alleviating some of these issues by exploring the use of a Genetic Algorithm (GA) approach combined with computer-aided design (CAD) and fused deposition modeling (FDM) techniques. Experiments were conducted using response surface methodology (RSM) to facilitate the optimisation process with build time and model material volume as responses. The validation of the study has been performed with a patella model and the results verified the effectiveness of the proposed RSM-GA approach in the design and development of the anatomical model. The results showed a 27% savings on model material compared to a non-refined model and was deemed satisfactory for practical use as there was a reduction in irregularities from CT data. The study also reveals that the parameter hollow has the largest effect on the responses, followed by the smooth parameter and then the wrap parameter.

Application of Rapid Prototyping in Prosthodontics

Purpose: Rapid Prototyping (RP) methods have for quite some time been utilized to construct complex 3-Dimensional (3D) models in the field of medicine since the 1900s. This paper intends to offer a thorough audit of different RP strategies, especially in Prosthodontics that are relied upon to carry numerous enhancements to this field.
 Materials and Methods: A pursuit was made using the Google scholar web and the PubMed database as a search engine. The keywords; ‘RP’, ‘rapid prototyping’, ‘3D printing’, ‘dentistry’ and ‘prosthodontics’, ‘stereolithography’, ‘selective laser sintering’, ‘fused deposition method’, and ‘inkjet-based system’ were looked at in the title/abstract of distributions. References of selected articles were additionally looked into for conceivable incorporation in the study. The selected articles utilized RP procedures in different fields of dentistry through various methods. Nonetheless, distributions concerning the dental utilization of RP advancements are as yet uncommon.
 Results: Although the concept of layering 3D objects is almost as old as human civilization, this technology has only lately been applied to the construction of 3D complex models in dentistry. Many additional methods appear to be on the horizon that could alter standard dentistry practises in the near future. More unit hours should be included in dentistry curriculums to familiarise dental professionals with the various advantages of this unique technology.
 Conclusion: Lately, RP using the property of adding substances or layering strategies have advanced quickly in different fields of dentistry as they can overcome known disadvantages of subtractive and regular procedures. RP has as of late proposed effective uses in different fields of dentistry, like fabrication of implant surgical guides, structures for Removable Partial Dentures (RPDs), Fixed Partial Dentures (FPDs), wax designs for the dental prosthesis, maxillofacial prosthesis, zirconia prosthesis, and molds for metal castings now as well for complete dentures.

Prediction of mechanical behaviors of L-DED fabricated SS 316L parts via machine learning.

Laser-based directed energy deposition (L-DED) is a rising field in the arena of metal additive manufacturing and has extensive applications in aerospace, medical, and rapid prototyping. The process parameters, such as laser power, scanning speed, and layer thickness, play an important role in controlling and affecting the properties of DED fabricated parts. Nevertheless, both experimental and simulation methods have shown constraints and limited ability to generate accurate and efficient computational predictions on the correlations between the process parameters and the final part quality. In this paper, two data-driven machine learning algorithms, Extreme Gradient Boosting (XGBoost) and Random Forest (RF), were applied to predict the tensile behaviors including yield strength, ultimate tensile strength, and elongation (%) of the stainless steel 316L parts by DED. The results suggest that both models successfully predicted the tensile properties of the fabricated parts. The performance of the proposed methods was evaluated and compared with the Ridge Regression by the root mean squared error (RMSE), relative error (RE), and coefficient of determination (R2). XGBoost outperformed both Ridge Regression and Random Forest in terms of prediction accuracy.

Application of Virtual Surgical Planning and Rapid Prototyping in Maxillofacial Trauma Surgery: A Case Series

Application of Virtual Surgical Planning and Rapid Prototyping in Maxillofacial Trauma Surgery: A Case Series

The Advent of Rapid Prototyping in Maxillofacial Prosthodontics – Exploring Into The Third Dimension

Rapid prototyping technology has opened new design and production possibilities in the realm of maxillofacial prosthodontics. Rapid prototyping is a technology that allows us to create physical objects from 3D computer data by sequential layering. Rapid prototyping has transformed dentistry with faster processing and increased precision of various prosthetic devices. This article attempts to enhance knowledge on history, materials used for rapid prototyping and an insight on applications of rapid prototyping in maxillofacial prosthodontics

Role of Additive Manufacturing in Investment Casting Process

Abstract: The aim of this study was to describe systematically the best available evidence of Additive manufacturing (AM) technology for different casting paths and How Rapid Investment casting (RIC) is revolutionizing the field of casting. The objective of this systematic review is to investigate the capabilities and effectiveness of Additive Manufacturing to provide an effective solution for investment casting production. Google Scholar, ResearchGate, Mendeley, ScienceDirect databases are used for research purposes. The conventional method of Investment Casting is less effective in terms of cost and time to develop new hard tooling wax patterns for low volume production and prototypes. To overcome this problem, we introduced additive manufacturing for making patterns for investment casting. This paper reviews the specific applications of Rapid prototyping in the field of casting. After applying the inclusion criteria, we found 40 articles for reviewing. This study concluded that using Additive manufacturing in Investment casting in place of the conventional method is more cost- effective and time-efficient. Keywords: Additive Manufacturing, Rapid Investment Casting.

An experimental study on the role of manufacturing parameters on the dry sliding wear performance of additively manufactured PETG

Abstract Additive manufacturing (AM) is a versatile and promising method for rapid prototyping and advanced design applications. Owing to its unique potential for fast production rates, and capacity of creating complex shapes, the number of researches on AM techniques have increased day by day in the technical literature. In this work, contrary to common literature efforts focused on mechanical properties, friction and wear behaviors of additively manufactured PETG samples were analyzed experimentally. As a methodology, fused filament fabrication (FFF) was selected. In order to explore the influence of manufacturing factors on wear properties, layer thickness (0.1, 0.2, and 0.3 mm), infill rate (40, 60, 80, and 100%), and building direction (vertical and horizontal) were changed. Before the friction tests, dimensional accuracy, hardness, and surface roughness measurements were conducted to interpret better the wear results. In addition, macroscopic and microscopic inspections were performed to determine the correct reason behind the deformation. From the data collected during the tests, there was a positive interaction between volume loss and layer thickness. Besides, there was no direct interaction between infill rate/building direction and coefficient of friction. In comparison with vertically built samples, horizontally built samples were subjected to more plastic deformation, and their worn surfaces were severely damaged.

Dimensional Accuracy of 3D - Printed Acrylonitrile Butadiene Styrene: Effect of Size, Layer Thickness, and Infill Density

The adoption of Additive Manufacturing (AM) is continuously growing due to its capability to produce complex shapes which leads to the dependence of manufacturers on AM to replace conventional manufacturing processes. One important focus of research now is on the accuracy of 3D printed products produced via the Fused Deposition Modeling (FDM). These products have great potential to be applied to tooling and other rapid prototyping applications. The aim of this study is to assess the accuracy of 3D printed Acrylonitrile Butadiene Styrene (ABS) through manual measurements of dimensions. Several sets of samples with cubic shapes were printed and measured using a digital micrometer to evaluate the dimensional accuracy of the 3d-printed parts. A 22 full factorial design was employed to investigate the effects of infill density and layer thickness on the dimensional accuracy of ABS parts.

Promoting Technology-Enhanced Project-Based Learning through Application of 3D Printing Technology for Mechanical Engineering Education

3D printing is a progressively developing technology under umbrella of industrial revolution 4.0 for rapid prototyping and end-use applications. 3D printing technology is nowadays used in all sectors including automotive, civil, agriculture, medical, aerospace, art and jewelry, and education too. In this work, 3D printing technology is employed as a technology-enhanced tool in engineering education in combination with project-based learning for third-year undergraduates. The combined technology-enhanced project-based learning strategy was used to 3D print components of internal combustion engines to enhance students' comprehension of the fundamentals of internal combustion engines. The activity resulted in improvement in the performance of students in the examination (5.15% improvement in CO attainment and more than 10% improvement in all modes of written examination) as well as professional skill development promoting multidisciplinary learning opportunities and lifelong learning. Keywords—3D printing; engineering education; IR4.0; project-based learning; technology-enhanced active learning. JEET Category—Choose one: Research, Practice, or Op-Ed. (Please note, Op-Eds are by invite only. Refer to the Paper Submission and Review Guidelines for more details.)

Effect of infill pattern and infill density on mechanical behaviour of FDM 3D printed Parts- a current review

Additive Manufacturing (AM) offers flexibility in customising, designing, minimising waste, faster prototyping and manufacturing complex profiles. The process parameters play a crucial role in the mechanical strength of the 3D printed product. The paper's objective is to provide a concise review of additive manufacturing techniques, focusing on the Fused Deposition Method (FDM) and its process parameters, mainly infill pattern and infill density and its effect on the physical behaviour of 3D printed parts. The article also includes the functional and industrial applications of rapid prototyping. The article's contribution is to explain to the researchers from academics and industry how and why infill density and infill pattern affect the mechanical properties of the 3D printed part.