Rapid Prototyping Research Articles

Affordable droplet-based flow analyzer with peristaltic micro-pumps for fluorescent ammonium sensing

An affordable droplet-based flow analyzer incorporating peristaltic micro-pumps has been developed for fluorescent ammonium sensing. The cost-effective peristaltic micro-pumps, modified using 3D-printing techniques, feature a 3D-printed pump base integrated with a Hall sensor to monitor the rotation of the pump motor. This setup generates a pulse flow instead of a continuous flow, delivering specific volumes (typically between 3 to 4 μL) of solution with each rotation. By using separate pumps to deliver the aqueous and oil phases, these phases merge to form a droplet flowing stream. The relative standard deviation (RSD) values for droplet volumes range from 3.97 % to 5.99 % (n=50) across different pumps. The analyzer utilizes a reaction between ammonium, ortho-phthalaldehyde, and sulfite to produce a fluorescent derivative, allowing for sensitive detection of low ammonium concentrations. A custom light-emitting diode (LED)-based fluorescence detector has been fabricated using 3D printing, ensuring cost-effective production. The analyzer provides a limit of detection of 0.02 μM (3σ) and an RSD of 0.15 % (n=10, 1 μM ammonium). This analyzer offers several practical advantages, including reduced reagent consumption and the potential for further development in distributed on-site analysis. The use of 3D printing facilitates rapid prototyping and customization, making the system adaptable to various analytical applications.

One-step rapid prototyping of recyclable ultrathin CNF/MWCNT/Fe-based spinel oxide asymmetric interdigital nanopaper electrodes for high performance flexible supercapacitors

Flexible asymmetric supercapacitors (FASCs) are potential energy storage devices for wearable electronics, considering that these have a wide operating voltage window, high specific capacity, and high energy density. However, achieving high energy density through the optimization of structure and electrode remains a challenge. Herein, two electrode inks with exceptional homogeneity nature and stability are prepared by using in-situ grown Fe-based spinel oxide (MFe2O4 = Fe3O4/MnFe2O4) on multi-walled carbon nanotubes (MWCNT) combined with eco-friendly and renewable cellulose nanofiber (CNF). Meanwhile, ultrathin flexible asymmetric interdigital nanopaper electrodes (NFT@MnFe and NFT@Fe) with customized patterns are fabricated through a one-step mask-assisted vacuum filtration strategy by using the obtained electrode inks. The planar interdigital FASC device based on the NFT@MnFe cathode and the NFT@Fe anode has excellent area specific capacity (309.8 mF cm−2), energy density (110.2 μW h cm−2), and power density (0.47 mW cm−2). The FASC maintain over 95 % of the original capacity after 5000 charge/discharge cycles. Noteworthy, a stacked interdigital FASC can be achieved with an energy density of up to 273.8 μW h cm−2 at 0.47 mW cm−2 power density, combining the structural benefits of planar interdigital and sandwich-type devices.

Dosage by design – 3D printing individualized cabozantinib tablets with immediate release

Production of patient-specific dosage forms is important to improve patient adherence and effectiveness while reducing the prevalence and severity of adverse effects. Due to its possibility of rapid prototyping 3D printing can be used to produce individual dosages while utilizing techniques such as hot melt extrusion to increase the bioavailability of poorly soluble drugs. In this work, Parteck MXP and Kollicoat IR were used as water-soluble polymer bases for formulation development for 3D printing of various dosages incorporating cabozantinib while enabling immediate release. The effect of tablet design and the excipients sorbitol, croscarmellose sodium, and sodium starch glycolate was investigated for this goal. A way to calculate the size of tablets for predetermined dosages is proposed to enable the printing of individual strengths from one formulation. Rheological data were collected to deepen the understanding of the role of melt viscosity in 3D printing and hot melt extrusion processes. The production of immediate-release cabozantinib tablets containing every therapeutically relevant dosage in a single unit produced by two-step 3D printing was realized.

3D-printed electrochemical cells for multi-point aptamer-based drug measurements.

Electrochemical aptamer-based (E-AB) sensors achieve detection and quantitation of biomedically relevant targets such as small molecule drugs and protein biomarkers in biological samples. E-ABs are usually fabricated on commercially available macroelectrodes which, although functional for rapid sensor prototyping, can be costly and are not compatible with the microliter sample volumes typically available in biorepositories for clinical validation studies. Seeking to develop a multi-point sensing platform for sensor validation in sample volumes characteristic of clinical studies, we report a protocol for in-house assembly of 3D-printed E-ABs. We employed a commercially available 3D stereolithographic printer (FormLabs, $5k USD) for electrochemical cell fabrication and directly embedded electrodes within the 3D-printed cell structure. This approach offers a reproducible and reusable electrode fabrication process resulting in four independent and simultaneous measurements for statistically weighted results. We demonstrate compatibility with aptamer sequences binding antibiotics and antineoplastic agents. We also demonstrate a proof-of-concept validation of serum vancomycin measurements using clinical samples. Our results demonstrate that 3D-printing can be used in conjunction with E-ABs for accessible, rapid, and statistically meaningful validation of E-AB sensors in biological matrices.

RSVP for VPSA : A Meta Design Study on Rapid Suggestive Visualization Prototyping for Visual Parameter Space Analysis.

Visual Parameter Space Analysis (VPSA) enables domain scientists to explore input-output relationships of computational models. Existing VPSA applications often feature multi-view visualizations designed by visualization experts for a specific scenario, making it hard for domain scientists to adapt them to their problems without professional help. We present RSVP, the Rapid Suggestive Visualization Prototyping system encoding VPSA knowledge to enable domain scientists to prototype custom visualization dashboards tailored to their specific needs. The system implements a task-oriented, multi-view visualization recommendation strategy over a visualization design space optimized for VPSA to guide users in meeting their analytical demands. We derived the VPSA knowledge implemented in the system by conducting an extensive meta design study over the body of work on VPSA. We show how this process can be used to perform a data and task abstraction, extract a common visualization design space, and derive a task-oriented VisRec strategy. User studies indicate that the system is user-friendly and can uncover novel insights.

Investigation of compressive strength of primitive geometries printed through the fused deposition modeling technique with different path patterns

Fused Deposition Modeling (FDM) is a material-extrusion-based technique used primarily for rapid prototyping and sometimes for an actual servicing part. In the FDM technique, input parent materials are commercial polymers. FDM also has some manufacturing parameters, and the raster pattern significantly affects the mechanical performance of the FDM products. Due to its intrinsic nature, Acrylonitrile Butadiene Styrene (ABS) is widely used in many industries, such as automobiles, medicine, etc. Producing the primitive geometry and selecting the proper infill pattern is challenging. Therefore, the current research paper investigates the effects of various infill patterns on the compressive performance of the three geometries (sphere, 3-side, and 4-side pyramids) printed through the FDM technique out of ABS material. The compressive experiments were conducted on the printed samples and load-displacement curves were evaluated. The results reveal that the concentrate path pattern in the sphere samples has the highest compressive failure load (40127 N). Also, the compressive failure loads in the 3-side and 4-side pyramids fabricated with a 45°/−45° raster pattern are 30444 N and 44396 N, respectively. Finally, comprehensive discussions about the obtained results are stated.

An Algorithm for Coding an Additive Manufacturing File from the Pressure Distribution of a Baropodometric Board for 3D Printing Customised Orthopaedic Insoles

Customised orthotic insoles play a critical role in addressing foot pathologies and improving comfort and biomechanical alignment for patients with specific needs. The use of 3D printing technology for the manufacturing of orthotic insoles has received considerable attention in recent years due to its potential for customisation, rapid prototyping, and cost-effectiveness. This paper presents the implementation of an algorithm purposely developed to generate an Additive Manufacturing File (AMF) containing the geometry of a patient-specific insole and the stiffness distribution based on pressure analysis from a baropodometric board. The generated file is used to 3D print via Fused Deposition Modelling an insole with a variable infill percentage depending on the pressure distribution on the patient’s foot. Three inputs are used as source data for the AMF file coding: (i) the 3D model that defines the geometry of the insole designed by the orthopaedist; (ii) the pressure map of the patient’s feet obtained with a baropodometric board; and (iii) the stiffness of the material that will be used to fabricate the insole. The proposed approach allows the fabrication of a patient-specific insole, capable of restoring the correct pressure distribution on the foot by varying the infill percentage. Two types of insoles were successfully fabricated using the implemented algorithm: the first was 3D printed, adding a top layer to be ready-to-use; the second was 3D printed without a top surface to be further customised with different coatings. The method described in this paper is robust for the fabrication of customised insoles and aims at overcoming the limitations of the traditional approach based on milling machining (e.g., time, costs, and path planning) since it can be easily integrated into any orthopaedic workshop.

A Droplet Generator Using Piezoelectric Ceramics to Impact Metallic Pellets.

Metal micro-droplet ejection technology has attracted attention for its potential applications in the rapid prototyping of micro-metal parts and microelectronic packaging. The current micro-droplet ejection device developed based on this technology faces challenges such as the requirement of a micro-oxygen ejection environment, a complex feeding structure, and high costs. Therefore, a drop-on-demand droplet generator for metallic pellets with impact feed ejection is designed in this paper. This device has a simple and compact structure, does not require a high-cost heat source, and can perform drop-on-demand ejection of metallic pellets in an atmospheric environment. A micro-channel feeding method based on piezoelectric ceramic actuator drives is proposed. A rigid dynamics metallic pellet flight trajectory model is established to analyze the relationships between the driving voltage and the flight trajectory of the pellets. With the help of Fluent to simulate and analyze the melting and ejection processes of the pellets inside the nozzle, the changes in the variable parameters of the flow field in the process of the melting and flight of a single molten drop are studied. The droplet generator produces stable droplets with a 500 µs pulse width and 1100 mm/s initial velocity of the projectile. The simulation results show that a single projectile has to go through three stages including feeding, melting, and ejecting, which take 39.5 ms, 7.85 ms, and 17.65 ms. The total simulation time is 65.0 ms. It is expected that the injection frequency of the metal projectile droplet-generating device will reach 15 Hz.

An investigation on the wear properties of the photocurable components produced by additive manufacturing for dentistry applications: Combined influences of UV exposure time, building direction, and sliding loads

AbstractAdditive manufacturing (AM) of polymers is a highly versatile technology that can be applied to many independent sectors like automotive, aviation, medicine, and dentistry. Since it has great potential for rapid prototyping, clean‐process concepts, and the ability to produce complex shapes, the layer‐by‐layer printing method is one of the most promising alternatives for future industrial production efforts. In that sense, different from the previous studies, this work aims to elucidate the friction and wear properties of the special dental samples manufactured via photopolymerization‐based AM technology according to both for printing parameters, and dry sliding test variables. Also, this is the first initiation to examine the combined influences of the UV exposure time, building direction, and sliding force on the surface roughness, hardness, friction coefficient, wear rate, and main plastic damage mechanism of the printed samples. The results showed that the maximum average hardness value was detected as 89.8 Shore D for vertically built samples printed with 8 s exposure time. In addition, vertically printed samples exhibited better wear resistance than the horizontal samples and the rising exposure time generally affected affirmatively the hardness levels of the samples. The lowest volume loss of 78 mm3 belonged to the vertical sample at 5 N. Further, increasing test force levels caused a decrease in the friction coefficient results and triggered the volume loss increase in the samples. Among all samples, the calculated friction coefficient values changed between 0.3 and 0.87. On the other side, scanning electron microscopy (SEM), and energy‐dispersive spectroscopy (EDS) analyses pointed out that ascending exposure times led to the altering contact surface matchings determining the final volume loss outcomes.Highlights To obtain better surface quality, vertical printing was a useful option. Horizontally printed samples exhibited higher friction coefficients. Curing time positively impacted the wear resistance for both orientations. Grooves and debris parts were observed on surfaces with low exposure times.

Virtual rapid prototyping of materials with deep learning: spatiotemporal stress fields prediction in ceramics employing convolutional neural networks and transfer learning

ABSTRACT Additive manufacturing offers a solution for producing advanced ceramics with complex geometries by enabling precise control over geometry, microstructure, and composition. By leveraging deep learning, rapid prototyping and evaluation of printed ceramic parts become feasible. This study employs convolutional neural networks and transfer learning to predict spatiotemporal fields in ceramics, using synthetic datasets generated from X-ray computed tomography (micro-CT) and finite element analysis. The novel approach integrates spatiotemporal factors into deep learning models, enhancing the prediction of stress and damage evolution, and ultimately providing deeper insights into material behaviour and performance. Additionally, we introduce a target loss training strategy, which focuses on achieving a specific accuracy level, thus reducing training time while maintaining high precision. The proposed deep learning framework achieves accurate predictions of spatiotemporal stress fields, and captures fracture initiation and propagation behaviours. This method facilitates rapid prototyping and advances material design and evaluation processes while significantly reducing experimental efforts.

Unveiling the reinforcement benefits of innovative textured geogrids

The smooth surface texture of the commercially available geogrids limits the shear strength mobilization at the interfaces. This study presents the design, manufacturing, and interface performance evaluation of innovative textured geogrids. Geogrids with square, triangular, and hexagonal apertures with and without inherent surface texture were manufactured through additive manufacturing (3D printing) technique, using PLA (Poly Lactic Acid) filament. The texture includes elevated pins of 3 mm height at the junctions and inherent diamond pattern of 1 mm height on the ribs. The individual and combined effects of surface texture and aperture shape on the stress–displacement relationship, dilation angle, and the thickness of shear zone are quantified using large-scale direct shear tests and Particle Image Velocimetry (PIV) analysis. Results showed that the textured geogrid with hexagonal aperture has exhibited the maximum interface coefficient of 0.96 with sand followed by the geogrids with triangular and square apertures. Irrespective of the aperture shape, provision of the surface texture resulted in an overall increase of interface shear strength by more than 13%. Further, PIV analysis revealed that the shear zone is 25% thicker for textured geogrids of different aperture shapes, suggesting higher interlocking and passive resistance offered by their textured surfaces.

Advances in 3D bioprinting for environmental remediation and hazardous materials treatment.

The high-throughput method based on the micron-level structure that 3D bioprinting technology offers for various environmental microbiological engineering applications is made possible by its several printing paths and precision programming control. This versatility makes it an on-demand manufacturing technology. A novel 3D manufacturing technique called 3D bioprinting may be used to precisely uptake and disperse bacteria to create microbial active substances with a variety of intricate functionalities for environmental applications. The technological challenges that the current 3D bioprinting technology must face include the mechanical properties of materials, the creation of specific bioinks to adapt to different strains, and the exploration of 4D bioprinting for intelligent applications. Therefore, this analysis delves deeply into the core technological ideas of 3D bioprinting, bioink materials, and their environmental applications. It also offers recommendations about the challenges and opportunities associated with 3D bioprinting. Combined with the present advancements in microbe enhancement technology, 3D bioprinting will provide an enabling platform for multifunctional microorganisms and facilitate the management of in situ directional responses in the environmental domain. This review highlights the applications of 3D bioprinting in the environmental monitoring and bioremediation. 3D printing in solid waste management is also discussed in detail.

Do makerspaces affect entrepreneurship? If so, who, how, and when?

AbstractResearch SummaryMakerspaces are physical spaces that offer individuals fabrication tools and materials (e.g., 3D printers) to make artifacts. Although not designed specifically for entrepreneurs, these spaces offer affordable access to rapid prototyping infrastructure. This study examines whether makerspaces affect entrepreneurship and, if so, who, how, and when. Leveraging hand‐collected data on US makerspaces and large archival data on Kickstarter projects, I show that makerspaces positively affect entrepreneurial participation and subsequent commercialization outcomes. However, these effects are mostly specific to hardware (vs. nonhardware) activities that typically involve physical prototypes. I find that the effect on entry is driven more by new (vs. established) but intentional (vs. accidental) entrepreneurs and that the effect on commercialization comes from two operating and complementary channels—resource provision and social facilitation.Managerial SummaryDespite a few high‐profile anecdotal entrepreneurial successes that emerged from the increasingly popular makerspaces, whether these spaces have large‐scale effects on entrepreneurship remains unclear. Do makerspaces encourage entrepreneurial participation, if so, who? Do makerspaces benefit entrepreneurial commercialization, if so, how? Are there any conditions determining when these effects would occur? This study demonstrates meaningful broad‐based impacts of makerspaces on particular types of entrepreneurship with growth potential. The findings suggest that competitive, prominent accelerators and incubators are not the only avenues for entrepreneurs to achieve commercialization success. Useful insights are discussed for entrepreneurial program managers and policy makers designing systems and structures that support inclusive prosperity for entrepreneurs.

Clinical and Radiographic Evaluation of Soft Tissue and Bone Status in Immediate Loaded Implants Placed Following Their Extraction in the Maxillary Anterior Region.

In the maxillary anterior region, teeth extraction leads to significant soft and hard tissue changes. Immediate implant placement following extraction aims to reduce bone loss and overall treatment time. However, it may result in adverse soft tissue changes impacting esthetics. This study evaluates the clinical and radiographic outcomes of immediately loaded implants in the maxillary anterior region, focusing on soft tissue preservation and bone status. This study, conducted from April 2022 to August 2024 at the Department of Oral and Maxillofacial Surgery, Ragas Dental College and Hospital, included 10 immediately loaded implants in seven patients. Following atraumatic extraction, implants were placed and loaded with functional provisional crowns fabricated using three-dimensional (3D) rapid prototyping models. Parameters such as crestal bone loss, buccal and palatal bone width, and interdental papilla thickness were evaluated preoperatively and postoperatively using radiographsand clinical assessments. The study found significant crestal bone loss at both mesial and distal sites over time, with the greatest loss observed at the three-month follow-up. Buccal and palatal bone width showed no significant differences preoperatively and postoperatively. Interdental papilla thickness and overall pink esthetic scores also showed no significant differences between preoperative and postoperative evaluations. Immediate implant placement in the maxillary anterior region, using 3D rapid prototyping for custom splint fabrication, demonstrated effective preservation of soft tissue profile and bone architecture. This approach provides functional and esthetic benefits, although careful monitoring of crestal bone loss is necessary.

Dismantling Silos: Academia, Industry, and a Science Museum Working Together

ABSTRACT A partnership between four universities, an industrial research lab, and a public science museum, created as a National Science Foundation Science and Technology Center, offers diverse collaboration and learning opportunities in cellular engineering. Each institution plays a vital role: universities advance science education, industry develops and commercializes technologies based on basic research, and science museums educate and engage the public. However, differences in the culture, values, and focus of these institutions create collaboration challenges. Three workshops highlight how consistent funding, intellectual property agreements, shared facilities, and long-term collaborations can harness the strengths of each institution to promote rapid prototyping, confront global problems, and encourage commercial applications from research.

Sustainable Support Material for Overhang Printing in 3D Concrete Printing Technology

The advantage of 3DCP technologies is the ability to fabricate free-form structures. However, printing openings in concrete structures are limited by the presence of overhanging sections. While various 3D printing and additive manufacturing technologies have established methods for handling overhangs with temporary supports, many existing techniques for 3D concrete printing still rely on wooden planks and corbelling, which restrict the design flexibility and slope angles. The objective of this study is to develop a removable and sustainable support material with high printability performance. This support material serves as temporary support for overhang sections in 3D-printed structures and can be removed once the primary concrete has hardened sufficiently. This study observed that increasing the recycled glass content in the mixture raises both the dynamic and static yield stresses, with only mixtures containing up to 60% recycled glass remaining pumpable. Optimization of the mixture design aimed to balance high flowability and buildability, and the results indicated that a mixture with 60% recycled glass content is optimal. The effectiveness of the optimized support material was validated through the successful printing of a structure featuring a free-form opening and overhang section.

Additively Manufactured Ceramics for Compact Quantum Technologies

AbstractQuantum technologies are advancing from fundamental research in specialized laboratories to practical applications in the field, driving the demand for robust, scalable, and reproducible system integration techniques. Ceramic components can be pivotal thanks to high stiffness, low thermal expansion, and excellent dimensional stability under thermal stress. Lithography‐based additive manufacturing of technical ceramics is explored, especially for miniaturized physics packages and electro‐optical systems. This approach enables functional systems with precisely manufactured, intricate structures, and high mechanical stability while minimizing size and weight. It facilitates rapid prototyping, simplifies fabrication and leads to highly integrated, reliable devices. As an electrical insulator with low outgassing and high temperature stability, printed technical ceramics such as and AlN bridge a technology gap in quantum technology and offer advantages over other printable materials. This potential is demonstrated with CerAMRef, a micro‐integrated rubidium D2 line optical frequency reference on a printed micro‐optical bench and housing. The frequency instability of the reference is comparable to laboratory setups while the volume of the integrated spectroscopy setup is only . Potential for future applications is identified in compact atomic magnetometers, miniaturized optical atom traps, and vacuum system integration.

In situ 3D polymerization (IS-3DP): Implementing an aqueous two-phase system for the formation of 3D objects inside a microfluidic channel.

Rapid prototyping and fabrication of microstructure have been revolutionized by 3D printing, especially stereolithography (SLA) based techniques due to the superior spatial resolution they offer. However, SLA-type 3D printing faces intrinsic challenges in multi-material integration and adaptive Z-layer slicing due to the use of a vat and a mechanically controlled Z-layer generation. In this paper, we present the conceptualization of a novel paradigm which uses dynamic and multi-phase laminar flow in a microfluidic channel to achieve fabrication of 3D objects. Our strategy, termed "in situ 3D polymerization," combines in situ polymerization and co-flow aqueous two-phase systems and achieves slicing, polymerization, and layer-by-layer printing of 3D structures in a microchannel. The printing layer could be predicted and controlled solely by programming the fluid input. Our strategy provides generalizability to fit with different light sources, pattern generators, and photopolymers. The integration of the microfluidic channel could enable high-degree multi-material integration without complicated modification of the 3D printer.

Fabrication of customized microneedle with high 3D capability and high structural precision

Advanced 3D fabrication techniques are essential for the processing of 3D devices, which mainly focusing on excellent 3D fabrication capability and high structural precision. Although 3D printing technology allows for the creation of complex 3D structures with extensive customization, it faces notable challenges in achieving precise micro/nanostructures within materials due to incomplete resin curing bonds. Here, we propose integrating projection micro-stereolithography (PμSL) with femtosecond (fs) laser Bessel beam drilling to create 3D structures with advanced customization, precise structures (including size accuracy and aspect ratio), and efficient processing. Starting with the drilling process using Bessel beams, we have achieved micro-holes with a diameter of approximately 1μm and the aspect ratio reached 1017:1 on 3D printed items by regulating the transparency and elasticity of the products. Furthermore, we have applied this technology to produce tailor-made microneedles, including slanted-tip microneedles and porous microneedles, demonstrating its ability for extensive, efficient micro-hole processing with a peak drilling speed of 200,000 holes per second. This technology offers an innovative approach to creating three-dimensional devices with intricate cavity structures, and its impressive processing capabilities suggest potential for broad industrial implementation.

In-house manufactured 3D guides for the localization and treatment of mandibular lesions. Workflow and case series

The anatomical location of certain lesions can be a difficulty when locating them intraoperatively. The use of surgical navigation allows anatomical structures to be located with great precision. However, there are technical difficulties with its use in mandibular surgery. Three-dimensional (3D) printing has established itself as a definitive tool in the generation of biomodels for diagnosis and treatment as well as implantable devices. Some applications, little explored today, have to do with the use of 3D-printed devices for the localization of hard-to-reach lesions. To determine the position of mandibular bone lesions, we propose using 3D printed localization guides manufactured “in-house,” using freely licensed design programs (software) to design them, and made of biocompatible resins. This improves surgical precision and reduces morbidity from the intervention. 3D planning models are shown and segmented using open-source software (3D Slicer) using imported conventional computed tomography data. Digital component modification is possible with free software (Autodesk Meshmixer) to arrange precise osteotomy cuts for lesion localization. With the help of customized cutting guides, intraoperative placement is precise. These are created utilizing a fused filament manufacturing 3D printer and polylactic acid. Three localization guides were successfully completed, resulting in improved surgical accuracy and reduced surgical morbidity. The use of 3D surgical guides in cases of mandibular lesions in difficult or delicate locations saves the need for navigation, requires less surgical time, does not require splints or reference stars.