articles+ search results

printing, additive manufacturing (AM), ceramics, rectangular waveguides, rapid prototyping, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, and QD1-999

Ceramic materials are chemical- and temperature-resistant and, therefore, enable novel application fields ranging from automotive to aerospace. With this in mind, this contribution focuses on developing an additive manufacturing approach for 3D-printed waveguides made of ceramic materials. In particular, a special design approach for ceramic waveguides, which introduces non-radiating slots into the waveguides sidewalls, and a customized metallization process, are presented. The developed process allows for using conventional stereolithographic desktop-grade 3D-printers. The proposed approach has, therefore, benefits such as low-cost fabrication, moderate handling effort and independence of the concrete waveguide geometry. The performance of a manufactured ceramic WR12 waveguide is compared to a commercial waveguide and a conventionally printed counterpart. For that reason, relevant properties, such as surface roughness and waveguide geometry, are characterized. Parsing the electrical measurements, the ceramic waveguide specimen features an attenuation coefficient of 30–60 dB/m within the E-Band. The measured attenuation coefficient is 200% and 300% higher compared to the epoxy resin and the commercial waveguide and is attributed to the increased surface roughness of the ceramic substrate.

overconstrained mechanisms, kinematical analysis, automotive application, virtual prototyping, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, and QD1-999

The paper presents some possible applications started from a six revolute joints (6R) overconstrained mechanism. The spatial devices obtained are based on the 6R Wohlhart symmetric mechanism in a special spatial position, with three non-adjacent joints constrained to remain in a fixed plane. This special spatial disposition allows us to obtain some reconfigurable/foldable devices, with an estimated application in the automotive industry field.

integrated intelligent CAD system, springs, parametric 3D modelling, FEM analysis, prototyping, C#, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, and QD1-999

This paper presents the development and implementation of integrated intelligent CAD (computer aided design) system for design, analysis and prototyping of the compression and torsion springs. The article shows a structure of the developed system named Springs IICAD (integrated intelligent computer aided design). The system bounds synthesis and analysis design phases by means of the utilization of parametric 3D (three-dimensional) modeling, FEM (finite element method) analysis and prototyping. The development of the module for spring calculation and system integration was performed in the C# (C Sharp) programming language. Three-dimensional geometric modeling and structural analysis were performed in the CATIA (computer aided three-dimensional interactive application) software, while prototyping is performed with the Ultimaker 3.0 3D printer with support of Cura software. The developed Springs IICAD system interlinks computation module with the basic parametric models in such a way that spring calculation, shaping, FEM analysis and prototype preparation are performed instantly.

design method, joint design, segmentation, additive manufacturing, rapid prototyping, fused deposition modeling (FDM), Technology, Engineering design, and TA174

Rapid prototyping has become increasingly popular over the past years. However, its application is heavily confined to a part size that fits the small build volume of additive machines. This paper presents a universal design method to overcome this limitation while preserving the economic advantages of rapid prototyping over conventional processes. It segments large, thin-walled parts and joins the segments. The method aims to produce an assembly with minimal loss to the performance and characteristics of a solid part. Based on a set of requirements, a universal segmentation approach and a novel hybrid joint design combining adhesive bonding and press fitting are developed. This design allows for the force transmission, positioning, and assembly of the segments adaptive to their individual geometry. The method is tailored to fused deposition modeling (FDM) by minimizing the need for support structures and actively compensating for manufacturing tolerances. While a universal application cannot be guaranteed, the adaptive design was proven for a variety of complex geometries. Using automotive trim parts as an example, the usability, benefits, and novelty of the design method is presented. The method itself shows a high potential to overcome the build volume limitation for thin-walled parts in an economic manner.

sculpture, arduino, marble, design, carving tool, prototyping, Electronics, and TK7800-8360

The art of sculpting is related to the processing of brittle materials, such as granite, marble, and stone, and is implemented using percussive hand tools or rotational roughing tools. The outcome of percussion carving is still directly related to the technique, experience, and capacity of the sculptor. Any attempt to automate the art of sculpturing is exhausted in the subtraction method of brittle materials using a rotating tool. In the process of percussion carving, there is no equivalent expertise. In this work, we present the design, manufacturing (3D printing and CNC machining), and use of a smart, percussion carving tool, either manually by the hand of a sculptor, adjusted in a percussive pneumatic hammer, or guided by a digitally driven machine. The scope is to measure and record the technological variables and sizes that describe and document the carving process through the sensors and electronic devices that the smart tool incorporates, the development and programming of which was implemented for the purposes of this work. The smart carving tool was meticulously tested in various carving stones and stressing scenarios to test the functionality and efficacy of the tool. All the tests were successfully implemented according to the specifications set.

neural network, variable step size, maximum power point tracking, incremental conductance method, Electronics, and TK7800-8360

In conventional adaptive variable step size (VSS) maximum power point tracking (MPPT) algorithms, a scaling factor is utilized to determine the required perturbation step. However, the performance of the adaptive VSS MPPT algorithm is essentially decided by the choice of scaling factor. In this paper, a neural network assisted variable step size (VSS) incremental conductance (IncCond) MPPT method is proposed. The proposed method utilizes a neural network to obtain an optimal scaling factor that should be used in current irradiance level for the VSS IncCond MPPT method. Only two operating points on the characteristic curve are needed to acquire the optimal scaling factor. Hence, expensive irradiance and temperature sensors are not required. By adopting a proper scaling factor, the performance of the conventional VSS IncCond method can be improved, especially under rapid varying irradiance conditions. To validate the studied algorithm, a 400 W prototyping circuit is built and experiments are carried out accordingly. Comparing with perturb and observe (P&O), α-P&O, golden section and conventional VSS IncCond MPPT methods, the proposed method can improve the tracking loss by 95.58%, 42.51%, 93.66%, and 66.14% under EN50530 testing condition, respectively.

polydimethylsiloxane, PDMS properties, PDMS applications, microfluidics, biomedical engineering, Biotechnology, TP248.13-248.65, Medicine (General), and R5-920

Polydimethylsiloxane (PDMS) is an elastomer with excellent optical, electrical and mechanical properties, which makes it well-suited for several engineering applications. Due to its biocompatibility, PDMS is widely used for biomedical purposes. This widespread use has also led to the massification of the soft-lithography technique, introduced for facilitating the rapid prototyping of micro and nanostructures using elastomeric materials, most notably PDMS. This technique has allowed advances in microfluidic, electronic and biomedical fields. In this review, an overview of the properties of PDMS and some of its commonly used treatments, aiming at the suitability to those fields’ needs, are presented. Applications such as microchips in the biomedical field, replication of cardiovascular flow and medical implants are also reviewed.

additive manufacturing, 3D printing, tag, traceability, provenance, anti-counterfeiting, Technology, Electrical engineering. Electronics. Nuclear engineering, TK1-9971, Engineering (General). Civil engineering (General), TA1-2040, Microscopy, QH201-278.5, Descriptive and experimental mechanics, and QC120-168.85

Additive manufacturing (AM) is rapidly evolving from “rapid prototyping” to “industrial production”. AM enables the fabrication of bespoke components with complicated geometries in the high-performance areas of aerospace, defence and biomedicine. Providing AM parts with a tagging feature that allows them to be identified like a fingerprint can be crucial for logistics, certification and anti-counterfeiting purposes. Whereas the implementation of an overarching strategy for the complete traceability of AM components downstream from designer to end user is, by nature, a cross-disciplinary task that involves legal, digital and technological issues, materials engineers are on the front line of research to understand what kind of tag is preferred for each kind of object and how existing materials and 3D printing hardware should be synergistically modified to create such tag. This review provides a critical analysis of the main requirements and properties of tagging features for authentication and identification of AM parts, of the strategies that have been put in place so far, and of the future challenges that are emerging to make these systems efficient and suitable for digitalisation. It is envisaged that this literature survey will help scientists and developers answer the challenging question: “How can we embed a tagging feature in an AM part?”.

additive manufacturing, electronic skin, Low-Force Stereolithography, room-temperature-vulcanizing, RTV, single-walled carbon nanotubes, Technology, Electrical engineering. Electronics. Nuclear engineering, TK1-9971, Engineering (General). Civil engineering (General), TA1-2040, Microscopy, QH201-278.5, Descriptive and experimental mechanics, and QC120-168.85

The strategy of embedding conductive materials on polymeric matrices has produced functional and wearable artificial electronic skin prototypes capable of transduction signals, such as pressure, force, humidity, or temperature. However, these prototypes are expensive and cover small areas. This study proposes a more affordable manufacturing strategy for manufacturing conductive layers with 6 × 6 matrix micropatterns of RTV-2 silicone rubber and Single-Walled Carbon Nanotubes (SWCNT). A novel mold with two cavities and two different micropatterns was designed and tested as a proof-of-concept using Low-Force Stereolithography-based additive manufacturing (AM). The effect SWCNT concentrations (3 wt.%, 4 wt.%, and 5 wt.%) on the mechanical properties were characterized by quasi-static axial deformation tests, which allowed them to stretch up to ~160%. The elastomeric soft material’s hysteresis energy (Mullin’s effect) was fitted using the Ogden–Roxburgh model and the Nelder–Mead algorithm. The assessment showed that the resulting multilayer material exhibits high flexibility and high conductivity (surface resistivity ~7.97 × 104 Ω/sq) and that robust soft tooling can be used for other devices.

micromachining strategies, micro/mesoscale milling, 3D microfluidic structure, PMMA, PDMS, surface quality, Mechanical engineering and machinery, and TJ1-1570

In recent years, there has been an increased interest in exploring the potential of micro-and mesoscale milling technologies for developing cost-effective microfluidic systems with high design flexibility and a rapid microfabrication process that does not require a cleanroom. Nevertheless, the number of current studies aiming to fully understand and establish the benefits of this technique in developing high-quality microsystems with simple integrability is still limited. In the first part of this study, we define a systematic and adaptable strategy for developing high-quality poly(methyl methacrylate) (PMMA)-based micromilled structures. A case study of the average surface roughness (Ra) minimization of a cuboid column is presented to better illustrate some of the developed strategies. In this example, the Ra of a cuboid column was reduced from 1.68 μm to 0.223 μm by implementing milling optimization and postprocessing steps. In the second part of this paper, new strategies for developing a 3D microsystem were introduced by using a specifically designed negative PMMA master mold for polydimethylsiloxane (PDMS) double-casting prototyping. The reported results in this study demonstrate the robustness of the proposed approach for developing microfluidic structures with high surface quality and structural integrability in a reasonable amount of time.

SU-8, photoresist, polydimethylsiloxane (PDMS), maskless photolithography, grayscale photolithography, backside exposure, Mechanical engineering and machinery, and TJ1-1570

Organ-on-a-chip (OoC) and microfluidic devices are conventionally produced using microfabrication procedures that require cleanrooms, silicon wafers, and photomasks. The prototyping stage often requires multiple iterations of design steps. A simplified prototyping process could therefore offer major advantages. Here, we describe a rapid and cleanroom-free microfabrication method using maskless photolithography. The approach utilizes a commercial digital micromirror device (DMD)-based setup using 375 nm UV light for backside exposure of an epoxy-based negative photoresist (SU-8) on glass coverslips. We show that microstructures of various geometries and dimensions, microgrooves, and microchannels of different heights can be fabricated. New SU-8 molds and soft lithography-based polydimethylsiloxane (PDMS) chips can thus be produced within hours. We further show that backside UV exposure and grayscale photolithography allow structures of different heights or structures with height gradients to be developed using a single-step fabrication process. Using this approach: (1) digital photomasks can be designed, projected, and quickly adjusted if needed; and (2) SU-8 molds can be fabricated without cleanroom availability, which in turn (3) reduces microfabrication time and costs and (4) expedites prototyping of new OoC devices.

FDM, 3D printing, additive manufacturing, shear test, adhesion, Organic chemistry, and QD241-441

Additive Manufacturing (AM) became a popular engineering solution not only for Rapid Prototyping (RP) as a part of product development but as an effective solution for producing complex geometries as fully functional components. Even the modern engineering tools, such as the different simulation software, have a shape optimization solution especially for parts created by AM. To extend the application of these methods in this work, the failure properties of the 3D-printed parts have been investigated via shear test measurements. The layer adhesion can be calculated based on the results, which can be used later for further numerical modeling. In conclusion, it can be stated that the layer formation and the structure of the infill have a great influence on the mechanical properties. The layers formed following the conventional zig-zag infill style show a random failure, and the layers created via extruded concentric circles show more predictable load resistance.

Industry 4.0, Digital Twin, simulation modelling, Chemical technology, TP1-1185, Chemistry, and QD1-999

This article presents the most valuable and applicable open-source tools and communication technologies that may be employed to create models of production processes by applying the concept of Digital Twins. In recent years, many open-source technologies, including tools and protocols, have been developed to create virtual models of production systems. The authors present the evolution and role of the Digital Twin concept as one of the key technologies for implementing the Industry 4.0 paradigm in automation and control. Based on the presented structured review of valuable open-source software dedicated to various phases and tasks that should be realised while creating the whole Digital Twin system, it was demonstrated that the available solutions cover all aspects. However, the dispersion, specialisation, and lack of integration cause this software to usually not be the first choice to implement DT. Therefore, to successfully create full-fledged models of Digital Twins by proceeding with proposed open-source solutions, it is necessary to make additional efforts due to integration requirements.

additive manufacturing, 3d printing, china, Economics as a science, and HB71-74

Additive manufacturing - or three-dimensional (3D) printing - refers to a group of technologies characterised by an accelerating maturation trend, which allow the creation of three-dimensional objects based on digital models, by sequentially applying and integrating layers of various traditional and innovative materials, from metals, polymers and ceramics, to graphene and other nanomaterials and composites. The technologies have applications in a variety of industries, from consumer goods production, automotive and aircraft parts, architecture and construction, to medical services and devices, or research and defence. Globally, the additive manufacturing market, which includes equipment, materials and 3D printing as a service, as well as their applications for prototyping and rapid manufacturing, has been valued at USD 15.4billion in 2020, with existing projections reflecting a four-fold increase to USD 61.1 billion in 2027. By the same date, China – the current 'factory of the world' – is projected to have a significant but less than one-quarter share of the global market – USD14.5 billion – against the backdrop of existing gaps difficult to narrow down.

aphasia, assistive technology, storytelling, user-centered design, graphical user interface, usability tests, Chemical technology, and TP1-1185

Aphasia is a partial or total loss of the ability to articulate ideas or comprehend spoken language, resulting from brain damage, in a person whose language skills were previously normal. Our goal was to find out how a storytelling app can help people with aphasia to communicate and share daily experiences. For this purpose, the Aphasia Create app was created for tablets, along with Aphastory for the Google Glass device. These applications facilitate social participation and enhance quality of life by using visual storytelling forms composed of photos, drawings, icons, etc., that can be saved and shared. We performed usability tests (supervised by a neuropsychologist) on six participants with aphasia who were able to communicate. Our work contributes (1) evidence that the functions implemented in the Aphasia Create tablet app suit the needs of target users, but older people are often not familiar with tactile devices, (2) reports that the Google Glass device may be problematic for persons with right-hand paresis, and (3) a characterization of the design guidelines for apps for aphasics. Both applications can be used to work with people with aphasia, and can be further developed. Aphasic centers, in which the apps were presented, expressed interest in using them to work with patients. The Aphasia Create app won the Enactus Poland National Competition in 2015.

port community system, terminal operating system, navigation safety, logistics, e-freight, IoT-based monitoring, Chemical technology, and TP1-1185

Seaports are genuine, intermodal hubs connecting seaways to inland transport links, such as roads and railways. Seaports are located at the focal point of institutional, industrial, and control activities in a jungle of interconnected information systems. System integration is setting considerable challenges when a group of independent providers are asked to implement complementary software functionalities. For this reason, seaports are the ideal playground where software is highly composite and tailored to a large variety of final users (from the so-called port communities). Although the target would be that of shaping the Port Authorities to be providers of (digital) innovation services, the state-of-the-art is still that of considering them as final users, or proxies of them. For this reason, we show how a canonical cloud, virtualizing a distributed architecture, can be structured to host different, possibly overlapped, tenants, slicing the information system at the infrastructure, platform, and software layers. Resources at the infrastructure and platform layers are shared so that a variety of independent applications can make use of the local calculus and access the data stored in a Data Lake. Such a cloud is adopted by the Port of Livorno as a rapid prototyping framework for the development and deployment of ICT innovation services. In order to demonstrate the versatility of this framework, three case studies relating to as many prototype ICT services (Navigation Safety, e-Freight, and Logistics) released within three industrial tenants are here presented and discussed.

Shape memory polyurethane, Magnesium, 3D printing, Robust bone regeneration, Tight-contact, Materials of engineering and construction. Mechanics of materials, TA401-492, Biology (General), and QH301-705.5

Patients with bone defects suffer from a high rate of disability and deformity. Poor contact of grafts with defective bones and insufficient osteogenic activities lead to increased loose risks and unsatisfied repair efficacy. Although self-expanding scaffolds were developed to enhance bone integration, the limitations on the high transition temperature and the unsatisfied bioactivity hindered greatly their clinical application. Herein, we report a near-infrared-responsive and tight-contacting scaffold that comprises of shape memory polyurethane (SMPU) as the thermal-responsive matrix and magnesium (Mg) as the photothermal and bioactive component, which fabricated by the low temperature rapid prototyping (LT-RP) 3D printing technology. As designed, due to synergistic effects of the components and the fabrication approach, the composite scaffold possesses a homogeneously porous structure, significantly improved mechanical properties and stable photothermal effects. The programmed scaffold can be heated to recover under near infrared irradiation in 60s. With 4 wt% Mg, the scaffold has the balanced shape fixity ratio of 93.6% and shape recovery ratio of 95.4%. The compressed composite scaffold could lift a 100 g weight under NIR light, which was more than 1700 times of its own weight. The results of the push-out tests and the finite element analysis (FEA) confirmed the tight-contacting ability of the SMPU/4 wt%Mg scaffold, which had a signficant enhancement compared to the scaffold without shape memory effects. Furthermore, The osteopromotive function of the scaffold has been demonstrated through a series of in vitro and in vivo studies. We envision this scaffold can be a clinically effective strategy for robust bone regeneration.

Digital signal processor, Universal motor, Speed control, Hardware architecture, PI controller, dSPACE MicroAutoBox, Engineering (General). Civil engineering (General), and TA1-2040

Universal motors are widely used in household appliances. When traditionally powered by AC, current harmonics are created which cause overheating of the windings and electromagnetic compatibility problems affecting the lifespan of the motor. Considering the remarkable comeback of DC power and its prospects in the electrification of homes, this paper proposes a control strategy for universal motors powered by DC using the rapid control prototyping feature offered by the dSPACE MicroAutoBox. A PI controller is designed using dominant-pole compensation method. The control strategy is simulated in Matlab/Simulink, then implemented in the MicroAutoBox via the Real-Time Interface. The simulation results are compared with those acquired by implementation through a laboratory test bench built around the MicroAutoBox and a dual full-bridge driver. The experimental results show that the designed PI controller managed to eliminate the static error and increased significantly the system dynamic performance by 26.5% in simulation and by 23.5% in practice. The robustness of the proposed control strategy against randomized load disturbances is proved by experimental tests. Furthermore, a significant improvement in power quality is reported.

Puerarin, PLGA/TCP, Angiogenesis, Osteogenesis, Drug/device combination implant, Diseases of the musculoskeletal system, and RC925-935

Objectives: Large bone defect repair is a challenging clinical problem due to limited self-repair ability. A well-designed bone filling product should possess the ability to induce tissue in-growth and facilitate neovascularization and new bone formation. Puerarin has been used in clinics for a long time, and recently it was found to be able to promote osteogenesis. This study aimed to investigate a puerarin-based drug/delivery combination implant for promoting large bone defect repair. Methods: Puerarin was incorporated into the poly (lactic-co-glycolic acid)/β-calcium phosphate (PLGA/TCP, PT) to form a porous PLGA/TCP/Puerarin (PTP) composite scaffold by low-temperature rapid prototyping technology. Its structural and degradation were analyzed in vitro. Then we employed a rat calvarial critical size defect model to assess the potency of the PTP scaffold. MC3T3-E1 cells and EA. hy 926 ​cells were used to investigate the underlying mechanism. Results: PTP scaffold inherited all advantages of PT scaffold in structural, mechanical, and biodegradation, meanwhile puerarin stably and continuously released from PTP scaffold and lasted for 5 months in vitro. At 8 weeks after implantation, the PTP scaffold triggered new bone formation in the macro-pores of the scaffold and inside the scaffold accompanied by the degrading materials. The underlying mechanism revealed that the PTP scaffold induced vascular infiltration and recruit repair cells through stimulating vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2) expressions to promote angiogenesis and osteogenesis. Conclusion: Puerarin-enriched porous PTP scaffold was a promising local delivery system with sustained release of puerarin for facilitating defect repair through getting synergistic angiogenic and osteogenic effects. The Translational Potential of this Article: The PTP scaffold presents a potential drug/device combination medical implant for large bone defect repair, which also provides a new and innovative application for the “old drug” puerarin.

Graphene, Metamaterial, Metasurface, Antennas, Absorbers, Sensors, Materials of engineering and construction. Mechanics of materials, and TA401-492

Surface Plasmon Polaritons (SPPs) operating in mid-infrared up to terahertz (THz) frequencies have been traditionally manufactured on expensive metals such as gold, silver, etc. However, such metals have poor surface confinement that limits the optical applications of SPPs. The invention of graphene is a breakthrough in plasmon-based devices in terms of design, fabrication and applications, thanks to its plasmonic wave distribution, low-cost prototyping and its inherent reconfigurability. In addition, recent advancements in plasmon-based metamaterials and metasurfaces led to the elimination of the past constraints on regular optical devices, opening a new door in THz devices and applications. This paper provides an operational perspective of the advanced graphene-based electromagnetic devices, with a focus on graphene enabled antennas, absorbers and sensors, analyzing the strengths and limitations of various design methodologies.

cell-free expression, linear expression template, nuclease inhibition, genetic circuits, rapid prototyping, DNA aptamers, Biotechnology, and TP248.13-248.65

ocean technology, current energy, ocean energy, tidal energy, tidal power, renewable energy, Science, General. Including nature conservation, geographical distribution, and QH1-199.5

The global energy consumption has been on the rise since the last industrial revolution and continues to be. So far the demand could be satisfied by a mixture of conventional and renewable energies. With the global effort to eliminate conventional energies to stop the anthropological climate change, the demand for reliable and predictable renewable energies is growing. Under these circumstances, more attention is drawn towards the development of non-intermittent ocean energy systems. Apart from waves, thermal and salinity gradients, currents are an abundant and reliable ocean energy source. Inspired by state-of-the-art technology, a unique system for current energy, the Current Kite, is presented in the following paper. This tethered undersea kite (TUSK) consist of a wing to which a turbine is attached. The wing drags the turbine through the water in a certain trajectory, sweeping a large area at a relative speed that is several times the actual speed of the underwater current. In the following paper we present the general setup and design of our first and second prototype. The first prototype was build as a prove of concept. It was equipped with active steering and several on board sensors. With the second prototype the aim was to build a more sophisticated system, which would make the active steering redundant and use more efficient, circular flight paths. A wing which would adjust itself in the current and follow the predefined circular path, was designed using numerical simulations. To achieve this circular flight movement without twisting the electrical cable, a swivel and a stress reducer were designed and built to connect the TUSK as well as transfer electrical power to land. In addition the tracking-system was redesigned, communicating by modulation over the power line. This provides a fully autonomous ocean current power plant, which communicates in real time data and has a promising outlook in efficiency, regarding to the state of art. Due to Covid-19 regulations it was not possible to test the prototype. Therefore the paper mainly focuses on the design and construction process, up to the production of the TUSK.

Microfluidic device, 3D printing, On-Chip printing, Biocompatibility, Electronics, TK7800-8360, Technology (General), and T1-995

Biomedical in vitro sensors use cell cultures grown on sensor chips for drug testing, toxicological screening, studying pathologic processes in tissue and for personalized medicine. Microfluidic systems and chips bridge the gap of the biological micro world to our accessible macro world, creating the interface between e.g., cells on a chip to reservoirs and pumps. Prototype and low volume lab scale microfluidic devices have traditionally been realized by soft lithography using polydimethylsiloxane (PDMS) technology. Recently, rapid prototyping of microfluidic devices using direct 3D printing has become widely available. Usually, the 3D printed parts are (i) either stand-alone systems requiring only fluidic connections, or (ii) they need to be carefully aligned and skilfully attached to the rigid micro fabricated chip. This post-fabrication attachment is time-consuming and a frequent source of error. In this work the fabrication of the microchip and the microfluidic system have been integrated into a multi technology fabrication process. For the first time we demonstrate the “on-chip 3D printing” of a microfluidic attachment directly onto an in-house fabricated multi electrode array chip. The process uses a desktop-sized LCD resin printer and eliminates the time-consuming post-deposition alignment and attachment. Biocompatibility of the used resin was confirmed for murine fibroblasts and validates this multi technology approach for biomedical cell chips.

printing, electrospinning, polymer, lens, graphene, sensor, Organic chemistry, and QD241-441

Ultraviolet (UV) is widely used in daily life as well as in industrial manufacturing. In this study, a single-step postprocess to improve the sensitivity of a graphene-based UV sensor is studied. We leverage the advantage of electric-field-assisted on-demand printing, which is simply applicable for mounting functional polymers onto various structures. Here, the facile printing process creates optical plano-convex geometry by accelerating and colliding a highly viscous droplet on a micropatterned graphene channel. The printed transparent lens refracts UV rays. The concentrated UV photon energy from a wide field of view enhances the photodesorption of electron-hole pairs between the lens and the graphene sensor channel, which is coupled with a large change in resistance. As a result, the one-step post-treatment has about a 4× higher sensitivity compared to bare sensors without the lenses. We verify the applicability of printing and the boosting mechanism by variation of lens dimensions, a series of UV exposure tests, and optical simulation. Moreover, the method contributes to UV sensing in acute angle or low irradiation. In addition, the catalytic lens provides about a 9× higher recovery rate, where water molecules inside the PEI lens deliver fast reassembly of the electron-hole pairs. The presented method with an ultimately simple fabrication step is expected to be applied to academic research and prototyping, including optoelectronic sensors, energy devices, and advanced manufacturing processes.

Drones, CFD, MDO, Aircraft design, Open source, PSO, Computer engineering. Computer hardware, TK7885-7895, Electronic computers. Computer science, and QA75.5-76.95

Hybrid configurations in aircraft design are highly favorable as they can achieve the appropriate trade-offs required to develop a generalized unmanned aerial system (UAS). Rapid prototyping of such systems at the student level is challenging because commercial software is expensive and difficult to interlink with other tools for creating a multi-disciplinary design. We address this challenge by conceptualizing an aircraft design framework made entirely of open-source software, libraries, and in-house code. We then use this framework to design an all-electric unmanned aerial system with transitioning Vertical Take-off and Landing (VTOL) and Fixed-Wing (FW) modes. The UAV is capable of long-range surveillance up to 100 Kilometers and carrying a maximum relief payload of 1 kg while operating in an ad-hoc wi-fi network with a swarm of similar UAVs. A low fidelity particle swarm optimization algorithm (PSO) and a comprehensive propulsion architecture is also incorporated and validated against commercial software. To validate the design, a prototype is fabricated from glass-fiber and XPS foam, integrated with appropriate sensors and tuned using ArduPilot software. The results show that low-fidelity design is a safe starting point for prototyping under constrained timelines. The study is concluded by discussing the technical challenges of using free software, and some practical considerations while flight testing a UAV with a hybrid configuration.

adaptive management, decision analysis, endangered species, marsh birds, structured decision making, value of information, Ecology, QH540-549.5, General. Including nature conservation, geographical distribution, and QH1-199.5

Abstract Natural resource management decisions are often made in the face of uncertainty. The question for the decision maker is whether the uncertainty is an impediment to the decision and, if so, whether it is worth reducing uncertainty before or while implementing actions. Value of information (VoI) methods are decision analytical tools to evaluate the benefit to the decision maker of resolving uncertainty. These methods, however, require quantitative predictions of the outcomes as a function of management alternatives and uncertainty, in which predictions which may not be available at early stages of decision prototyping. Here we describe the first participatory application of a new qualitative approach to VoI in an adaptive management workshop for Atlantic Coast eastern black rail populations. The eastern black rail is a small, cryptic marsh bird that was recently listed as federally threatened, with extremely little demographic data available. Workshop participants developed conceptual models and nine hypotheses related to the effects of habitat management alternatives on black rail demography. Here, we describe the qualitative VoI framework, how it was implemented in the workshop, and the analysis outcomes, and describe the benefits of qualitative VoI in the context of adaptive management and co‐production of conservation science.

active collision avoidance system, driving intention inference, deep neural network, dropout regularization, electric vehicles, Electronics, and TK7800-8360

Driving intention, which can assist drivers to avoid dangerous emergence for the advanced driver assistant systems (ADAS), can be hardly described accurately for complex traffic environments. At present, driving intention can be mainly obtained by deep neural networks with neuromuscular dynamics and electromyography (EMG) signals of drivers. This method needs numerous drivers’ signals and neural networks with a complex structure. This paper proposes a driving intention direct inference method, namely direct inference from the road surface condition. A driving intention safety distance model based on a deep neural network with dropout regularization was built in an active collision avoidance control system of electric vehicles. Driving intention can be inferred by a deep neural network with dropout regularization from adhesion coefficients between the tire and road. Simulations using rapid control prototyping (RCP) and a hardware-in-the-loop (HIL) simulator were performed to demonstrate the effectiveness of the proposed driving intention safety distance model based on a deep neural network with dropout regularization. The proposed driving intention safety distance model can guarantee the safe driving of electric vehicles.

integer square root, non-restoring algorithm, FPGA design, pipelined data processing, Electronics, and TK7800-8360

The development of digital technologies is in many ways associated with an improvement of integrated technologies, microelectronic components, and the capabilities of hardware acceleration of the most computationally complex operations. Field-programmable gate arrays (FPGAs) are actively used for prototyping or the small-scale production of special purpose digital signal processing (DSP) devices. The implementation of DSP algorithms is variative in nature and affects important indicators of a produced device, such as the accuracy of the numerical solution, performance, structural/functional complexity, etc. The architectural features of the FPGA can be used for choosing an effective DSP algorithm in the form of solving the multicriteria discrete optimization problem. This paper analyzes and selects an effective algorithm for calculating the integer square root, which is one of the most frequently used digital signal processing operations. A behavioral model based on a non-restoring algorithm is presented. The SystemVerilog description of the module for calculating the square root, presented in the form of a universal configurable IP core, has been developed and synthesized. The configuration allows one to change the width of the input data bus and select the serial or parallel processing mode for scalar or vector data. The results of testing and comparison of the obtained characteristics with the corresponding Xilinx Cordic IP core are presented. The field test of the proposed IP core implemented in the Xilinx FPGA SOC xc7z045ffg900-2 has demonstrated the gain in the maximum system frequency at 174 MHz in the sequential mode with a 48-bit input bus and 169 MHz in the pipelined mode at a reduction of both the structural complexity and the number of used FPGA internal resources in comparison with the Xilinx Cordic IP core.

tube hydroforming, y-shaped joint, tubular metal forming, counter punch force, Mechanical engineering and machinery, TJ1-1570, Physics, and QC1-999

The design capability, strength, and structural rigidity provided by tube hydroforming (THF) are successfully used in many applications to produce high-strength parts and assemblies with improved mechanical properties, optimized service life, and weight features. In tubular metal forming, output parameters such as branch height, distribution of tube wall material thickness, distribution of damage factor, metal flow, effective stress, and effective strain significantly affect the quality of the product after the forming process. Therefore, this paper aims to evaluate the manufacturing quality of Y-shape joints from AISI304 material steel tube through output parameters of THF process with and without counter punch force on numerical simulation base. The Finite Element Method (FEM) has become an established feature of metal forming technology. The objective of FEM is to replace costly and elaborate experimental testing with fast, low-cost computer simulation. The simulation study uses finite element method-based virtual prototyping techniques to characterize output parameters, gain insight into strain mechanics, and predict mechanical properties of shaped components. The research results are presented clearly and unambiguously through the evaluation of 7 criteria to compare the quality of the specimens hydroformed by two surveyed cases and optimize the crucial input process parameters. And these data can be applied in experiments, more efficient product and process design, calculation, and control of input parameters avoiding costly trial and error in industrial production. The findings can help technologists optimize process parameters in the hydroforming process of products with protrusion from a tubular blank

conducting polymer, tissue engineering, conventional method, rapid prototyping, electrospinning, 3D printing, Biotechnology, and TP248.13-248.65

Conductive scaffolds, defined as scaffold systems capable of carrying electric current, have been extensively researched for tissue engineering applications. Conducting polymers (CPs) as components of conductive scaffolds was introduced to improve morphology or cell attachment, conductivity, tissue growth, and healing rate, all of which are beneficial for cardiac, muscle, nerve, and bone tissue management. Conductive scaffolds have become an alternative for tissue replacement, and repair, as well as to compensate for the global organ shortage for transplantation. Previous researchers have presented a wide range of fabrication methods for conductive scaffolds. This review highlights the most recent advances in developing conductive scaffolds, with the aim to trigger more theoretical and experimental work to address the challenges and prospects of these new fabrication techniques in medical sciences.

3D bioprinting, bioinks, scaffolds, biological materials, tissue repair and regeneration, and Technology

Three-dimensional (3D) printing technology has emerged as a revolutionary manufacturing strategy that could realize rapid prototyping and customization. It has revolutionized the manufacturing process in the fields of electronics, energy, bioengineering and sensing. Based on digital model files, powdered metal, plastic and other materials were used to construct the required objects by printing layer by layer. In addition, 3D printing possesses remarkable advantages in realizing controllable compositions and complex structures, which could further produce 3D objects with anisotropic functions. In recent years, 3D bioprinting technology has been applied to manufacture functional tissue engineering scaffolds with its ability to assemble complicated construction under precise control, which has attracted great attention. Bioprinting creates 3D scaffolds by depositing and assembling biological and/or non-biological materials with an established tissue. Compared with traditional technology, it can create a structure tailored to the patient according to the medical images. This conception of 3D bioprinting draws on 3D printing technology, which could be utilized to produce personalized implants, thereby opening up a new way for bio-manufacturing methods. As a promising tool, 3D bioprinting can create complex and delicate biomimetic 3D structures, simulating extracellular matrix and preparing high precision multifunctional scaffolds with uniform cell distribution for tissue repair and regeneration. It can also be flexibly combined with other technologies such as electrospinning and thermally induced phase separation, suitable for tissue repair and regeneration. This article reviews the relevant research and progress of 3D bioprinting in tissue repair and regeneration in recent years. Firstly, we will introduce the physical, chemical and biological characteristics of biological scaffolds prepared by 3D bioprinting from several aspects. Secondly, the significant effects of 3D bioprinting on nerves, skin, blood vessels, bones and cartilage injury and regeneration are further expounded. Finally, some views on the clinical challenges and future opportunities of 3D bioprinting are put forward.

simulator, neural population, population density, software, Python, dynamical systems, Neurosciences. Biological psychiatry. Neuropsychiatry, and RC321-571

Population density techniques can be used to simulate the behavior of a population of neurons which adhere to a common underlying neuron model. They have previously been used for analyzing models of orientation tuning and decision making tasks. They produce a fully deterministic solution to neural simulations which often involve a non-deterministic or noise component. Until now, numerical population density techniques have been limited to only one- and two-dimensional models. For the first time, we demonstrate a method to take an N-dimensional underlying neuron model and simulate the behavior of a population. The technique enables so-called graceful degradation of the dynamics allowing a balance between accuracy and simulation speed while maintaining important behavioral features such as rate curves and bifurcations. It is an extension of the numerical population density technique implemented in the MIIND software framework that simulates networks of populations of neurons. Here, we describe the extension to N dimensions and simulate populations of leaky integrate-and-fire neurons with excitatory and inhibitory synaptic conductances then demonstrate the effect of degrading the accuracy on the solution. We also simulate two separate populations in an E-I configuration to demonstrate the technique's ability to capture complex behaviors of interacting populations. Finally, we simulate a population of four-dimensional Hodgkin-Huxley neurons under the influence of noise. Though the MIIND software has been used only for neural modeling up to this point, the technique can be used to simulate the behavior of a population of agents adhering to any system of ordinary differential equations under the influence of shot noise. MIIND has been modified to render a visualization of any three of an N-dimensional state space of a population which encourages fast model prototyping and debugging and could prove a useful educational tool for understanding dynamical systems.

Amphibious robot, Kinematic modeling, Virtual prototype, ADAMS, Engineering (General). Civil engineering (General), and TA1-2040

The amphibious robot, which has the capability of multi-mode motion, can maneuver diverse environments with high mobility and adaptability. These are employed in the area of reconnaissance, search and rescue operations, and monitoring. The existing amphibious robots have lower maneuverability over the crawling period on uneven and slope surfaces on the land. In this paper, a kinematic model of the amphibious robot based on virtual prototyping is designed for multi-mode locomotion. ADAMS (Automated dynamic analysis of mechanical systems) is a multi-body dynamic solver adopted to build the simulation model for the robot. The novel amphibious robot employs a Rockerbogie mechanism equipped with wheel paddles. The locomotion analysis on land involves straight-going and obstacle negotiation, which is simulated using ADAMS. The simulation analysis result demonstrates increased maneuverability, achieving a robot's velocity of 1.6 m/s. Normal forces on the front and rear wheels show equal load distribution, contributing more to the robot’s equilibrium over uneven terrain. The simulation result reflects the accurate kinematic characteristics of the amphibious robot and provides a theoretical basis for developing an algorithm for robot motion control and optimization. Further, this research will concentrate on the kinematic simulation maneuvering in water mode with the wheel paddle. ABSTRAK: Robot amfibia yang memiliki berbilang mod pergerakan, dapat bergerak dalam persekitaran berbeza dengan ketinggian mobiliti dan adaptasi. Kebolehan ini dapat digunakan dalam kawasan pengintipan, operasi pencarian dan menyelamat, dan peninjauan. Robot amfibia sedia ada mempunyai kurang kebolehgerakan sepanjang tempoh merangkak pada permukaan cerun dan permukaan tidak rata pada tanah. Dalam kajian ini, model kinematik robot amfibia berdasarkan prototaip maya dibentuk berdasarkan gerak alih pelbagai mod. Sistem Mekanikal Analisis Dinamik Automatik (ADAMS) adalah penyelesai dinamik berbilang badan telah diadaptasi bagi membina model simulasi robot. Robot amfibia baru dicipta berdasarkan mekanisme Rockerbogie beserta padel tayar. Analisis gerak alih atas tanah ini termasuk gerakan-lurus dan rundingan halangan, disimulasi menggunakan ADAMS. Dapatan simulasi kajian menunjukkan peningkatan kebolehgerakan, mencapai halaju robot sehingga 1.6 m/s. Daya tujahan normal pada depan dan belakang tayar menunjukkan keseimbangan agihan beban, menyumbang lebih kepada keseimbangan robot ke atas permukaan yang tidak rata. Dapatan kajian dari simulasi menunjukkan ciri-ciri kinematik yang tepat pada robot amfibia dan menyediakan teori asas bagi membangunkan algoritma kawalan pergerakan dan pengoptimuman. Seterusnya, kajian ini mengfokuskan simulasi gerakan kinematik dalam mod air beserta padel tayar.

flash sintering (FS), oxygen vacancies, defect engineering, ZnO powders, electric discharge, Clay industries. Ceramics. Glass, and TP785-869

Abstract In this study, we reported that flash sintering (FS) could be efficiently triggered at room temperature (25 °C) by manipulating the oxygen concentration within ZnO powders via a versatile defect engineering strategy, fully demonstrating a promising method for the repaid prototyping of ceramics. With a low concentration of oxygen defects, FS was only activated at a high onset electric field of ∼2.7 kV/cm, while arcs appearing on the surfaces of samples. Strikingly, the onset electric field was decreased to < 0.51 kV/cm for the activation of FS initiated, which was associated with increased oxygen concentrations coupled with increased electrical conductivity. Thereby, a general room-temperature FS strategy by introducing intrinsic structural defect is suggested for a broad range of ceramics that are prone to form high concentration of point defects.

fused deposition modeling (FDM), fused filament fabrication (FFF), polylactic acid (PLA) filament, acrylonitrile butadiene styrene (ABS) filament, nondestructive testing (NDT), 3D printing, Technology, and Science

In this review, the potential failures and flaws associated with fused deposition modeling (FDM) or fused filament fabrication (FFF) 3D printing technology are highlighted. The focus of this article is on presenting the failures and flaws that are caused by the operational standpoints and which are based on the many years of experience with current and emerging materials and equipment for the 3D printing of polymers and composites using the FDM/FFF method. FDM or FFF 3D printing, which is also known as an additive manufacturing (AM) technique, is a material processing and fabrication method where the raw material, usually in the form of filaments, is added layer-by-layer to create a three-dimensional part from a computer designed model. As expected, there are many advantages in terms of material usage, fabrication time, the complexity of the part, and the ease of use in FDM/FFF, which are extensively discussed in many articles. However, to upgrade the application of this technology from public general usage and prototyping to large-scale production use, as well as to be certain about the integrity of the parts even in a prototype, the quality and structural properties of the products become a big concern. This study provides discussions and insights into the potential factors that can cause the failure of 3D printers when producing a part and presents the type and characteristics of potential flaws that can happen in the produced parts. Common defects posed by FDM printing have been discussed, and common nondestructive detection methods to identify these flaws both in-process and after the process is completed are discussed. The discussions on the failures and flaws in machines provides useful information on troubleshooting the process if they happen, and the review on the failures and flaws in parts helps researchers and operators learn about the causes and effects of the flaws in a practical way.

learning material, islamic context, conceptual understanding, validation, Mathematics, and QA1-939

This research was conducted to develop and produce Islamic context-based mathematic learning material. The presentation of Islamic context for pre-service mathematics teachers was intended to facilitate conceptual understanding. This learning material contains rank and root, ratio and scale, and material for flat shapes and spatial shapes. The material is included in the Mathematics Materials Study course for Junior Secondary Education in the Mathematics Teacher Education program. The method in this study uses design research with the type of development study with a qualitative approach. The research phases include the preliminary research phase, the development or prototyping phase, and the assessment phase. The data were collected by filling out a learning material scoring scale by Education and Language expert and an Islamic Study expert. The quality criteria for learning material have valid results if the experts score it with excellent and valid categories. Thus, they do not need significant revision. Based on the research results, the quality of Islamic context-based mathematics learning material is classified into valid criteria at a percentage of 84% according to Mathematics Education experts and a percentage of 83.3% according to Education and Language experts and classified as an excellent category at a percentage of 94% according to Islamic Study expert. Based on these results, the product of Islamic contextual mathematics teaching materials is suitable for use in mathematics lectures.

carbon black, reaction-bonded silicon carbide, free silicon, Technology, Electrical engineering. Electronics. Nuclear engineering, TK1-9971, Engineering (General). Civil engineering (General), TA1-2040, Microscopy, QH201-278.5, Descriptive and experimental mechanics, and QC120-168.85

Reaction-bonded silicon carbide (RBSC) has become an important structural ceramic with the benefit of being capable of preparing complex-shaped products. In order to fabricate high-performance RBSC, particle gradation of raw SiC combined with slip casting was used to prepare the porous preform before liquid silicon infiltration (LSI). The microstructural and mechanical properties of RBSC were compared by adding different amounts of carbon black (CB) content from 4 wt% to 10 wt%. Two pore structures with submicron and nano pores formed in the preform. As the amounts of carbon black increased, the mechanical properties improved and then suddenly weakened due to residual silicon initiating a nonuniform microstructure. The elastic modulus of the preform with 8 wt%CB after LSI was 389 ± 4 GPa and the flexural strength was 340 ± 17 MPa, which improved by about 150% compared to other rapid prototyping methods and has attractive application prospects.

mechanical ventilation, tracheostomy, dynatraq, alignment, tubes., Medical technology, and R855-855.5

Mauricio Orozco-Levi,1– 3 Carlos Reyes,4 Neikel Quintero,1 Diana Tiga-Loza,1– 3 Mabel Reyes,1– 3 Sandra Sanabria,5 Camilo Pizarro,4 Juan De Hoyos,5 Norma Serrano,6 Victor Castillo,5,7 Alba Ramírez-Sarmiento1– 3,6 1Respiratory Department, Hospital Internacional de Colombia, Fundación Cardiovascular de Colombia (FCV), Floridablanca, Santander, Colombia; 2Group of Research in Muscle, Training and Lung Diseases (EMICON), Ministerio de Ciencia y Tecnología (MINCIENCIAS), Bogotá, Cundinamarca, Colombia; 3Department of Medicine, and Facultad de Ciencias Médicas y de la Salud, Universidad de Santander (UDES), Bucaramanga, Santander, Colombia; 4Department of Critical Care, Hospital Internacional de Colombia, Fundación Cardiovascular de Colombia (FCV), Floridablanca, Santander, Colombia; 5Bioengineering Research Group, Fundación Cardiovascular de Colombia (FCV), Floridablanca, Santander, Colombia; 6Research Center, Fundación Cardiovascular de Colombia (FCV), Floridablanca, Santander, Colombia; 7CEO, Fundación Cardiovascular de Colombia (FCV), Floridablanca, Santander, ColombiaCorrespondence: Mauricio Orozco-Levi, Respiratory Department, Hospital Internacional de Colombia, Fundación Cardiovascular de Colombia, Calle 155A no. 23-58, El Bosque, Floridablanca, Santander, Colombia, Tel +57 3175741421, Email mauricioorozco@fcv.orgIntroduction: Tracheostomy is one of the most common surgical strategies in intensive care units (ICU) and provides relevant clinical benefit for multiple indications. However, the complications associated with its use range from 5 to 40% according to different series. The risk of these complications could be reduced if fixation strategies and alignment of the tracheostomy tube with respect to the tracheal axis are improved.Aim: To build a functional device of technological innovation in respiratory medicine for the fixation and alignment of tracheostomy cannula (acronym DYNAtraq) and to evaluate its feasibility and safety in a pilot study in mechanically ventilated patients.Methods: Study carried out in four phases: (1) design engineering and functional prototyping of the device; (2) study of cytotoxicity and tolerance to the force of traction and push; (3) pilot study of feasibility and safety of its use in tracheostomized and mechanically ventilated patients; and (4) health workers satisfaction study.Results: The design of the innovative DYNAtraq device included, on the one hand, a connector with very little additional dead space to be inserted between the cannula and the ventilation tubes, and, on the other hand, a shaft with two supports for adhesion to the skin of the thorax with very high tolerance (several kilograms) to pull and push. In patients, the device corrected the malpositioned tracheostomy tubes for the latero-lateral (p < 0.001) and cephalo-caudal angles (p < 0.001). Its effect was maintained throughout the follow-up time (p < 0.001). The use of DYNAtraq did not induce serious adverse events and showed a 70% protective effect for complications (RR = 0.3, p < 0.001) in patients.Conclusion: DYNAtraq is a new device for respiratory medicine that allows the stabilization, alignment and fixation of tracheostomy tubes in mechanically ventilated patients. Its use provides additional benefits to traditional forms of support as it corrects misalignment and increases tolerance to habitual or forced movements. DYNAtraq is a safe element and can reduce the complications of tracheostomy tubes.Keywords: mechanical ventilation, tracheostomy, DYNAtraq, alignment, tubes

autotransplantation of teeth, computer-aided rapid prototyping, virtual simulation, 3-dimensional printing, Medicine (General), and R5-920

The use of computer-aided rapid prototyping (CARP) models was considered to reduce surgical trauma and improve outcomes when autotransplantation of teeth (ATT) became a viable alternative for dental rehabilitation. However, ATT is considered technique-sensitive due to its series of complicated surgical procedures and unfavorable outcomes in complex cases. This study reported a novel autotransplantation technique of a 28-year-old patient with an unrestorable lower first molar (#36) with double roots. Regardless of a large shape deviation, a lower third molar (#38) with a completely single root formation was used as the donor tooth. ATT was performed with a combined use of virtual simulation, CARP model-based rehearsed surgery, and tooth replica-guided surgery. A 3D virtual model of the donor and recipient site was generated from cone-beam computed tomographic (CBCT) radiographs prior to surgery for direct virtual superimposition simulation and CARP model fabrication. The virtual simulation indicated that it was necessary to retain cervical alveolar bone during the surgical socket preparation, and an intensive surgical rehearsal was performed on the CARP models. The donor tooth replica was used during the procedure to guide precise socket preparation and avoid periodontal ligament injury. Without an additional fitting trial and extra-alveolar storage, the donor tooth settled naturally into the recipient socket within 30 s. The transplanted tooth showed excellent stability and received routine root canal treatment three weeks post-surgery, and the one-year follow-up examination verified the PDL healing outcome and normal functioning. Patient was satisfied with the transplanted tooth. This cutting-edge technology combines virtual simulation, digital surgery planning, and guided surgery implementation to ensure predictable and minimally invasive therapy in complex cases.

dual-phase steels, RAP approach, martensite morphology, heating rate, hot rolled microstructure, TNR temperature, Mining engineering. Metallurgy, and TN1-997

Microstructural morphology is known to have a significant impact on the mechanical properties of dual-phase steels. A fine ferrite grain size and random distribution of small second phase islands are desirable to provide superior isotropic properties compared to the banded second phase distribution that is typical for this type of steel. A rapid alloy prototyping (RAP) facility has been used to investigate three different DP 800 variants by systematically varying the compositions and/or process parameters compared to the ‘standard’ DP800 composition and processing that gives a banded microstructure. For Variant 1, the heating rate during the annealing cycle after cold rolling varied between 0.65 and 30 °C/s for the 45%, 60% and 75% cold reduction samples. It was found that a cold reduction of 75% and heating rate of 15 °C/s resulted in the microstructure that can give the best combination of strength and ductility because of the fine grain size and high martensite volume fraction. For Variant 2, the effect of changing the hot rolled (HR) microstructure (ferrite–pearlite, ferrite–bainite or martensite) on the final microstructure was investigated. Both the ferrite–50% bainite and fully martensite/bainite HR materials for all cold reductions resulted in annealed microstructures with necklace martensite morphology and finer ferrite grains compared to the ferrite–pearlite HR material, which gave a typical banded ferrite–martensite microstructure with a coarser ferrite grain size. For Variant 3, the Mn content was reduced, and increased Nb was used to achieve higher pancaking during the hot rolling stage, which refined ferrite grains in the HR condition with the same hardness. After annealing with the standard parameters only the 45% cold-reduced material produced a finer ferrite grain size than the standard material, whereas the 60% and 75% cold-reduced samples required a higher heating rate to achieve finer ferrite grain sizes due to rapid recrystallisation and growth kinetics.

bio-carbon content, polyester polyols, thermoplastic polyurethanes, prototyping, Organic chemistry, and QD241-441

To realize the commercialization of sustainable materials, new polymers must be generated and systematically evaluated for material characteristics and end-of-life treatment. Polyester polyols made from renewable monomers have found limited adoption in thermoplastic polyurethane (TPU) applications, and their broad adoption in manufacturing may be possible with a more detailed understanding of their structure and properties. To this end, we prepared a series of bio-based crystalline and amorphous polyester polyols utilizing azelaic acid and varying branched or non-branched diols. The prepared polyols showed viscosities in the range of 504–781 cP at 70 °C, with resulting TPUs that displayed excellent thermal and mechanical properties. TPUs prepared from crystalline azelate polyester polyol exhibited excellent mechanical properties compared to TPUs prepared from amorphous polyols. These were used to demonstrate prototype products, such as watch bands and cup-shaped forms. Importantly, the prepared TPUs had up to 85% bio-carbon content. Studies such as these will be important for the development of renewable materials that display mechanical properties suitable for commercially viable, sustainable products.

plasmonics, engineering education, meta-material, optical constants, electromagnetic modeling, nanoparticles, Chemistry, and QD1-999

Recent advances in nanoscale fabrication and characterization further accelerated research on photonics and plasmonics, which has already attracted long-standing interest. Alongside morphological constraints, phenomena in both fields highly depend on the materials’ optical properties, dimensions, and surroundings. Building up the required knowledge and experience to design next-generation photonic devices can be a complex task for novice and experienced researchers who intend to evaluate the impact of subtle material and morphology variations while setting up experiments or getting a general overview. Here, we introduce the Photonic Materials Cloud (PMCloud), a web-based, interactive open tool for designing and analyzing photonic materials. PMCloud allows identification of the subtle differences between optical material models generated from a database, experimental data input, and inline-generated materials from various analytical models. Furthermore, it provides a fully interactive interface to evaluate their performance in important fundamental (numerical) optical experiments. We demonstrate PMCloud’s applicability to state-of-the-art research questions, namely the comparison of the novel plasmonic materials aluminium-doped zinc oxide and zirconium nitride and the design of an optical, dielectric thin-film Bragg reflector. PMCloud opens a rapid, freely accessible path towards prototyping optical materials and simple fundamental devices and may serve as an educational platform for photonic materials research.

microcontrollers, data acquisition, variable speed drives, optical sensors, signal processing algorithms, Chemical technology, and TP1-1185

Precise motor control requires high accuracy of the rotor position through the incremental encoder. The speed and accuracy of the acquisition equipment (microcontroller) play an important element in terms of cost and efficiency. In this paper, the author presents alternative methods for speed acquisition from an incremental encoder. In the first stage of research, the main performances of the STM32 microcontroller, connected with an incremental encoder, will be analyzed and compared with two different acquisition systems, i.e., ELVIS II and a Unidrive M701 power inverter. Using the LabVIEW graphical programming language, a user-friendly, convenient, and flexible human–machine interface is designed. Due to the advantages provided by the STM32 microcontroller in terms of processing power, cost, and programming interface, the obtained results are accurate and consistent. Through experimental testing and analysis, the speed acquisition is stable for both developed software algorithms used for ELVIS II and STM32 platforms. It is the aim of the paper to propose a useful speed acquisition tool in low-cost, high-accuracy prototyping applications.

ROS, 3D Slicer, image-guided therapy, robotics, software, prototyping, Chemical technology, and TP1-1185

Developing image-guided robotic systems requires access to flexible, open-source software. For image guidance, the open-source medical imaging platform 3D Slicer is one of the most adopted tools that can be used for research and prototyping. Similarly, for robotics, the open-source middleware suite robot operating system (ROS) is the standard development framework. In the past, there have been several “ad hoc” attempts made to bridge both tools; however, they are all reliant on middleware and custom interfaces. Additionally, none of these attempts have been successful in bridging access to the full suite of tools provided by ROS or 3D Slicer. Therefore, in this paper, we present the SlicerROS2 module, which was designed for the direct use of ROS2 packages and libraries within 3D Slicer. The module was developed to enable real-time visualization of robots, accommodate different robot configurations, and facilitate data transfer in both directions (between ROS and Slicer). We demonstrate the system on multiple robots with different configurations, evaluate the system performance and discuss an image-guided robotic intervention that can be prototyped with this module. This module can serve as a starting point for clinical system development that reduces the need for custom interfaces and time-intensive platform setup.

precision agriculture, UGV, tractor, sensors, unmanned vehicles, Environmental effects of industries and plants, TD194-195, Renewable energy sources, TJ807-830, Environmental sciences, and GE1-350

In this study, a comprehensive overview of the available autonomous ground platforms developed by universities and research groups that were specifically designed to handle agricultural tasks was performed. As cost reduction and safety improvements are two of the most critical aspects for farmers, the development of autonomous vehicles can be of major interest, especially for those applications that are lacking in terms of mechanization improvements. This review aimed to provide a literature evaluation of present and historical research contributions toward designing and prototyping agricultural ground unmanned vehicles. The review was motivated by the intent to disseminate to the scientific community the main features of the autonomous tractor named BOPS-1960, which was conceived in the 1960s at the Alma Mater Studiorum University of Bologna (UNIBO). Jointly, the main characteristics of the modern DEDALO unmanned ground vehicle (UGV) for orchard and vineyard operations that was designed recently were evaluated. The basic principles, technology and sensors used in the two UNIBO prototypes are described in detail, together with an analysis of UGVs for agriculture conceived in recent years by research centers all around the world.

nanoparticles, self-assembly, printing technology, patterned structure, functional devices, Science (General), and Q1-390

Functional nanoparticles (NPs) with unique photoelectric, mechanical, magnetic, and chemical properties have attracted considerable attention. Aggregated NPs rather than individual NPs are generally required for sensing, electronics, and catalysis. However, the transformation of functional NP aggregates into scalable, controllable, and affordable functional devices remains challenging. Printing is a promising additive manufacturing technology for fabricating devices from NP building blocks because of its capabilities for rapid prototyping and versatile multifunctional manufacturing. This paper reviews recent advances in NP patterning based on the combination of self-assembly and printing technologies (including two-, three-, and four-dimensional printing), introduces the basic characteristics of these methods, and discusses various fields of NP patterning applications. Public summary: • Nanoparticles (NPs) printing assembly is a good solution for patterned devices • NPs assembly can be combined with 2D, 3D, and 4D printing technologies • A variety of ink-dispersed NPs are available for printing assembly • NPs printing assembly technology is applied for nanosensing, energy storage, photodetector

pedagogical prototyping, living labs, immersive education, nature-based solutions, circular bioeconomy, Architecture, and NA1-9428

Emerging designers and makers of the built environment have an outstanding responsibility and potential to mitigate and adapt to global climate change, environmental pollution, biodiversity loss, and resource depletion. This paper overviews how the Institute for Advanced Architecture of Catalonia – Valldaura Labs (VL) educates incipient practitioners in interdisciplinary strategies for unifying the constructed and natural worlds through pedagogical prototyping and learning by living. VL is a living lab sited 10 km from Barcelona’s centre in the Collserola Natural Park, hosting the immersive Master in Advanced Ecological Buildings & Biocities (MAEBB), which culminates in the annual autonomous design and fabrication of a self-sufficient building. The methods and projects of VL provide best practices of reference for realising holistically integrated ecological and technological landscapes.

3d printing, Additive manufacturing, Rapid prototyping, Surgery, Craniofacial, Maxillofacial, Medical technology, and R855-855.5

This systematic review aims to provide an overview of the published literature for three-dimensional printing (3DP) in cranio- and maxillofacial surgery applications utilizing either external laboratories (outsourced) or point-of-care (POC) fabrication facilities. Four digital databases (PubMed, Web of Science, Embase, and Cochrane Library) were systematically reviewed between January 2018 and December 2020. The review focused on the type of printed objects, the clinical indications, surgical outcome, time, cost, 3DP materials, and technologies used. Among the 2269 retrieved studies, 75 met the inclusion criteria. The studies that stated POC and outsourced production methods were 34.67% (n = 26) and 12% (n = 9). A large proportion of studies (54.67%, n = 41) did not specify the printing location. 3DP was used for surgeries of the entire craniomaxillofacial region, most specifically in mandibular reconstructions and orthognathic surgeries applications. Customized implants and osteosynthesis plates were exclusively printed in titanium using Powder Bed Fusion (PBF) 3DP technology. For surgical guides, models, and molds, Material Jetting, Material Extrusion, and Vat Photopolymerization, using either thermoplastic or photopolymeric resin materials were used. Medical 3DP is an assisting tool to plan, prepare, and even improve cranio- and maxillofacial surgery outcomes. With future technological advancement and research, 3DP has the potential to revolutionize cranio- and maxillofacial surgeries. With decreasing prices of three-dimensional (3D) printers and software packages, the disadvantage of the high acquisition and procurement costs for the hardware for in-house 3DP can be addressed and mitigated with time.

virtual reality laboratory, automotive industry, Education 4.0, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, and QD1-999

Knowledge transfer associated with education in the automotive manufacturing and production fields is challenging due to the requirements of physical prototyping of mechanical components and laboratory-assisted testing. In this regard, aspects of Industry 4.0 such as virtual environments and enhanced human–computer interaction have been studied as important resources to improve teaching practices and achieve the equivalent Education 4.0 paradigm. Within the context of modern manufacturing techniques in the Industry 4.0 era and advanced tools for analysis and mechanical design, the present work describes the development of a virtual/augmented reality (VR/AR) laboratory to support learning, training, and collaborative ventures related to additive manufacturing for the automotive industry. The development was performed in accordance with the guidelines of the ISO/IEC TR 23842-1 standard, to ensure that the academic programs and the conditions of use of the laboratory were optimal. Experiences with students through the development of industry-related automotive projects support confidence in the suitability of the laboratory and the expectation of positive outcomes for future developments.

Physics, QC1-999, Biology (General), and QH301-705.5

Super-resolution optical fluctuation imaging (SOFI) is a highly democratizable technique that provides optical super-resolution without requirement of sophisticated imaging instruments. Easy-to-use open-source packages for SOFI are important to support the utilization and community adoption of the SOFI method, they also encourage the participation and further development of SOFI by new investigators. In this work, we developed PySOFI, an open-source Python package for SOFI analysis that offers the flexibility to inspect, test, modify, improve, and extend the algorithm. We provide complete documentation for the package and a collection of Jupyter Notebooks to demonstrate the usage of the package. We discuss the architecture of PySOFI and illustrate how to use each functional module. A demonstration on how to extend the PySOFI package with additional modules is also included in the PySOFI package. We expect PySOFI to facilitate efficient adoption, testing, modification, dissemination, and prototyping of new SOFI-relevant algorithms.