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.

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.

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

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.

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.

3D printing, Fused deposition modeling (FDM), Tensile strength, Thermoplastics, Polylactic acid (PLA), Design of experiments (DOE), and Technology

Fused deposition modeling (FDM), one of various additive manufacturing (AM) technologies, offers a useful and accessible tool for prototyping and manufacturing small volume functional parts. Polylactic acid (PLA) is among the commonly used materials for this process. This study explores the mechanical properties and print time of additively manufactured PLA with consideration to various process parameters. The objective of this study is to optimize the process parameters for the fastest print time possible while minimizing the loss in ultimate strength. Design of experiments (DOE) was employed using a split-plot design with five factors. Analysis of variance (ANOVA) was employed to verify the model significance or otherwise. Once the model was developed, confirmation points were run to validate the model. The model was confirmed since the observations at the optimum were within the prediction interval with a confidence value of 95%. Then, the model was used to assess the ultimate strength and print time of FDM parts with consideration to nozzle diameter, the number of outer shells, extrusion temperature, infill percentage, and infill pattern. Recommendations are discussed in detail in this study to reduce print time without sacrificing significant part strength.

Bone regeneration, Hydroxyapatite, Larnite, Scaffold, Selective laser melting, Wollastonite, Clay industries. Ceramics. Glass, and TP785-869

Additive manufacturing is a rapid prototyping technology to produce complex three-dimensional scaffolds suitable for personalized medicine. In the present study, the laser powder bed fusion through a selective laser melting (SLM) approach has been applied to optimized fabrication of bio-mimicking scaffolds by using hydroxyapatite (HAp, 50 and 70 wt%) and silicon powder mixture. In situ formation of pseudo-wollastonite (P–W, CaSiO3) has been detected along with silicon for 50 wt% of HAp powder mixture, while an increase in HAp content has resulted in P–W, silicon and larnite (Ca₂SiO₄) formation. The pore size of 400 μm, according to the CAD model, are observed at the scaffolds fabricated at the shortest exposure time (50 μs), lowest laser current (500 mA) and energy density (41.6 J/mm3), and simultaneously at the highest scanning speed. Compressive stress demonstrated by the fabricated scaffolds is shown to be acceptable for their use in metaphyseal region of long bones.

Contiki-NG, Internet of Things, Resource-Constrained Devices, Computer software, and QA76.75-76.765

Contiki-NG (Next Generation) is an open source, cross-platform operating system for severely constrained wireless embedded devices. It focuses on dependable (reliable and secure) low-power communications and standardised protocols, such as 6LoWPAN, IPv6, 6TiSCH, RPL, and CoAP. Its primary aims are to (i) facilitate rapid prototyping and evaluation of Internet of Things research ideas, (ii) reduce time-to-market for Internet of Things applications, and (iii) provide an easy-to-use platform for teaching embedded systems-related courses in higher education. Contiki-NG started as a fork of the Contiki OS and retains many of its original features. In this paper, we discuss the motivation behind the creation of Contiki-NG, present the most recent version (v4.7), and highlight the impact of Contiki-NG through specific examples.

Multiphase, Singlephase, Relative permeability, Permeability, Lattice-Boltzmann, Porous media, Computer software, and QA76.75-76.765

MPLBM-UT is a specialized lattice-Boltzmann library that makes running single- and two-phase flow simulations in porous media accessible to everyone. We provide a suite of tools to pre-process computational domains for simulation, to set up custom boundary conditions, to run simulations, to post-process simulation outputs, and to visualize simulation results and data. All of these tools are easily accessible to users through the mplbm_utils Python package included in and automatically installed with MPLBM-UT. The high-performance, highly parallel library Palabos is used as the solver backend. MPLBM-UT is easily deployed in a variety of systems, from laptops to supercomputer clusters. MPLBM-UT also features multiple examples and benchmark templates that allow for fast prototyping of different porous media problems. We also provide an interface for reading in different file types and downloading domains from the Digital Rocks Portal to perform simulations.

Combinatorial optimization, Hyper-heuristics, Job shop scheduling, Matlab, MatHH, Computer software, and QA76.75-76.765

Hyper-Heuristics (HHs) have proven to be a valuable tool for solving complex problems, such as Combinatorial Optimization Problems (COPs). These solvers have an assorted set of models arising through extensive research from the scientific community. Hence, it is customary that researchers develop their models from scratch, which increases development times. Drafting and testing new ideas become burdensome and time-consuming. In this work, we present MatHH, a Matlab-based framework to allow rapid prototyping of HHs. We summarize the architecture and some examples of their usage. We also discuss some research questions that upcoming research may explore through MatHH.

Cycling infrastructure, Distance to parking cars, Cycling simulator, Online survey, Rapid prototyping, Method comparison, Transportation and communications, and HE1-9990

Marked on-road infrastructure for bicycle riders is a fast and cost-efficient way to expand cycling infrastructure and thus promote cycling as a means of transport. Infrastructure layout has been shown to influence cyclists’ as well as car drivers’ behavior towards cyclists in traffic observations, with on-street markings for cyclists in some circumstances reducing overtaking distances by car drivers. Simulator and online studies promise to provide a fast and easy way of rapid prototyping infrastructure layouts. But, despite of good face validity, how trustworthy are the results of both these research tools? In a case-study to inform planning authorities, two studies, one in a cycling simulator and an online survey, evaluated the effects of different on-street markings from bicycle riders’ perspectives. Results showed that in mixed traffic stronger visual separation between parking cars and flowing traffic and a bicycle pictogram on the road induced greater lateral distance of bicycle riders from parking cars. This infrastructure layout was also rated as safe, comfortable, and comprehensible from bicycle riders’ perspectives. From a methods’ evaluation perspective, effects from the cycling simulator may be interpreted as behaviorally valid relatively between conditions only. Both methods offer a cost-effective approach to initially test infrastructure solutions by weeding out the less favorable ones in the early stages of the design.

Internet of Things, remote prototyping, FPGA devices, undergraduate teaching, digital design and synthesis lab, COVID-19 lockdowns, Electronics, and TK7800-8360

This paper presents a system for the remote design and testing of electronic circuits and devices with FPGAs during COVID-19 and similar lockdown periods when physical access to laboratories is not permitted. The system is based on the application of the IoT concept, in which the final device is a test board with an FPGA chip. The system allows for remote visual inspection of the board and the devices linked to it in the laboratory. The system was developed for remote learning taking place during the lockdown periods at Poznan University of Technology (PUT) in Poland. The functionality of the system is confirmed by two demonstration tasks (the use of the temperature and humidity DHT11 sensor and the design of a generator of sinusoidal waveforms) for students in the fundamentals of digital design and synthesis courses. The proposed solution allows, in part, to bypass the time-consuming simulations, and accelerate the process of prototyping digital circuits by remotely accessing the infrastructure of the microelectronics laboratory.

battery safety, electrical vehicles, socio-technical system, rapid prototyping, stakeholders, policy, and Technology

Battery technology is crucial in the transition towards electric mobility. Lithium-ion batteries are conquering the market but are facing fire safety risks that might threaten further applications. In this study, we address the problem and potential solutions for traction batteries in the European Union area. We do so by taking a unique socio-technical system perspective. Therefore, a novel, mixed-method approach is applied, combining literature review; stakeholder interviews; Failure Mode, Mechanisms, and Event Analysis (FMMEA); and rapid prototyping. Our findings confirm that fire safety is an upcoming concern. Still, most stakeholders lack a full understanding of the problem. Improving safety is a shared responsibility among supply chain and societal stakeholders. For automotive applications, voluntary standard-setting on safety risks is an appropriate tool to improve fire safety, whereas for niche applications, a top-down approach setting regulations seems more suited. For both groups, the adaptation of battery pack designs to prevent thermal runaway propagation is shown to be promising from a technological, practical, and organizational perspective. The chosen mixed-method approach allowed for a holistic analysis of the problems and potential solutions. As such, it can serve as an empowerment strategy for stakeholders in the field, stimulating further discussion, agenda building, and action.

Maxillofacial reconstruction, Temporalis flap, Temporal hollowing, Computer-assisted surgery, Patient-specific implants, Rapid prototyping, Dentistry, RK1-715, Surgery, and RD1-811

Abstract Background Temporal hollowing is a common complication following the rotation of the temporalis muscle that leaves the patient with a cosmetic impairment. Several alloplastic materials have been used to reconstruct the donor site; however, these implants need meticulous adaptation to conform the periphery of the defect and restore the contour of the temporal area. The aim of this study was to assess the use of patient-specific polyetheretherketone (PEEK) temporal implants to prevent temporal hollowing following the use of full temporalis muscle flap for large maxillary defects reconstruction. Methods This was a prospective study conducted on eight patients with major maxillary defects indicating the need of reconstruction with full temporalis muscle flap or any lesion indicating major maxillary resection and immediate reconstruction with total temporalis muscle flap. For each patient, a patient-specific PEEK implant was fabricated using virtual planning and milled from PEEK blocks. In the surgical theater, the temporalis muscle was exposed, elevated, and transferred to the maxilla. After the temporalis muscle transfer, PEEK implants were fixed in place to prevent temporal hollowing. Results The surgical procedures were uneventful for all patients. The esthetic result was satisfactory with no post-operative complications except in one patient where seroma occurred after 2 weeks and resolved after serial aspiration. Conclusion Patient-specific PEEK implant appears to facilitate the surgical procedures eliminate several meticulous steps that are mainly based on the surgeon’s experience. Trial registration Clinical trials registration: NCT05240963 .

battery modelling, laser-structured electrodes, 3D battery concept, lithium-ion battery, multi-physics multi-domain modelling, virtual optimisation, Chemistry, and QD1-999

An electrochemical multi-scale model framework for the simulation of arbitrarily three-dimensional structured electrodes for lithium-ion batteries is presented. For the parameterisation, the electrodes are structured via laser ablation, and the model is fit to four different, experimentally electrochemically tested cells. The parameterised model is used to optimise the parameters of three different pattern designs, namely linear, gridwise, and pinhole geometries. The simulations are performed via a finite element implementation in two and three dimensions. The presented model is well suited to depict the experimental cells, and the virtual optimisation delivers optimal geometrical parameters for different C-rates based on the respective discharge capacities. These virtually optimised cells will help in the reduction of prototyping cost and speed up production process parameterisation.

design thinking, empathy, problem definition, product testing, prototyping, Business, and HF5001-6182

Entrepreneurial activities seek to fill the gaps created by the government’s inability to employ their citizens globally. However, design thinking, which is a human-centered and solution-based approach to problem-solving can enhance entrepreneurial success. This study investigates design thinking and business success in Nigeria. The purpose was to determine how design thinking influences business success using the five-stage model of design thinking as its framework. The study employed a quantitative methodology. The design was a cross-sectional survey of 224 out of 350 randomly selected online respondents that were invited. The respondents, who were either entrepreneurs or people with knowledge of entrepreneurial education at the undergraduate or postgraduate levels, were contacted through social media (Facebook and WhatsApp) and a structured questionnaire was used to elicit information from them. The data were analyzed using the structural equation modeling technique. Empathy, problem definition, ideation, prototyping, and product testing were found to be positively related to business success. However, while the positive relationships between empathy, problem definition, prototyping, and product testing were found to be significant at a 1% level, that of ideation was not significant at all; thus, empathy, problem definition, prototyping, and product testing are predictors of business success. Consequently, at a 99% confidence level, it is concluded that empathy, problem definition, prototyping, and product testing, and by implication, entrepreneurial design thinking, are significant predictors of business success.

Fiber optics sensor, Soil water measurements, Distrubuite fiber optic sensors, Fiber Bragg Grating, Smart farming, Optics. Light, and QC350-467

Real time measurements of soil water content play a critical role in many fields of science as agronomy, geology, engineering, and hydrology. In the last years, agriculture has become one of the most important application fields of soil water sensors technology in order to optimize the irrigation process and to guarantee sustainable water resources management. This work provides a review on the latest emerging methodologies based on optical fiber sensing for soil moisture monitoring for agricultural and hydrological applications. In particular, the main studies referring to optical fiber sensors based on a variation of the refractive index of the external medium, sensors based on heated distributed temperature sensor (HDTS) and sensors based on Fiber Bragg Gratings (FBG) or Long Period Gratings (LPG) are here explored. Finally, some approaches based on the NIR absorbance spectroscopy are proposed for measuring the soil water content. Most of these approaches and technologies are still in a prototyping phase and only few of them are properly evaluated in situ real context.

multi-axis, magnetic tactile sensor, robotic surgery, force range, Hall sensor, elastomer, Chemical technology, and TP1-1185

This paper presents a multi-axis low-cost soft magnetic tactile sensor with a high force range for force feedback in robotic surgical systems. The proposed sensor is designed to fully decouple the output response for normal, shear and angular forces. The proposed sensor is fabricated using rapid prototyping techniques and utilizes Neodymium magnets embedded in an elastomer over Hall sensors such that their displacement produces a voltage change that can be used to calculate the applied force. The initial spacing between the magnets and the Hall sensors is optimized to achieve a large displacement range using finite element method (FEM) simulations. The experimental characterization of the proposed sensor is performed for applied force in normal, shear and 45° angular direction. The force sensitivity of the proposed sensor in normal, shear and angular directions is 16 mV/N, 30 mV/N and 81 mV/N, respectively, with minimum mechanical crosstalk. The force range for the normal, shear and angular direction is obtained as 0–20 N, 0–3.5 N and 0–1.5 N, respectively. The proposed sensor shows a perfectly linear behavior and a low hysteresis error of 8.3%, making it suitable for tactile sensing and biomedical applications. The effect of the material properties of the elastomer on force ranges and sensitivity values of the proposed sensor is also discussed.

autonomy, memristors, microrobots, simulation, time awareness, Computer engineering. Computer hardware, TK7885-7895, Control engineering systems. Automatic machinery (General), and TJ212-225

Micrometer‐scale robots capable of navigating enclosed spaces and remote locations are approaching reality. However, true autonomy remains an open challenge despite substantial progress made with externally supervised and manipulated systems. To accelerate the development of autonomous microrobots, alternatives to conventional top‐down lithography are sought. Such additive technologies like printing, coating, and colloidal self‐assembly allow for rapid prototyping and access to novel materials, such as polymers, bio‐ and nanomaterials. On the basis of recent experimental findings that memristive networks can be rapidly printed and lifted off as electronic microparticles, an alternative design paradigm is introduced based on arrays of two‐terminal memristive elements, which enables real‐time use of memory, sensing, and actuation in microrobots. Several memristor‐based designs are validated, each representing a key building block toward robotic autonomy: tracking elapsed time, timestamping a rare event, continuously cataloguing time‐indexed data, and accessing the collected information for a feedback‐controlled response as in a robotic glucose‐responsive insulin. The computational results establish an actionable framework for microrobotic design—tasks normally requiring complex circuits can now be achieved with self‐assembled and printed memristor arrays within microparticles.

FPGA, rapid prototyping, Simulink, HDL Coder, Xilinx Zynq, Zedboard, Electronics, and TK7800-8360

Many advanced power electronics control techniques present a steep computational load, demanding advanced controllers, such as FPGAs. However, FPGA development is a daunting and time-consuming task, inaccessible to most users. This paper proposes a complete methodology for prototyping power electronics with Xilinx Zynq-based boards using Matlab/Simulink and HDL Coder. Even though these tools are relatively well documented, and several works in the literature have used them, a methodology for developing power electronics systems with them has never been proposed. This paper aims to address that, by proposing a complete programming and design methodology for Zynq-based power electronics and discussing important drawbacks and hurdles in Simulink/HDL Coder development, as well as their possible solutions. In addition, techniques for the implementation of all required peripherals (ADCs, digital outputs, etc.), system protections, and real-time data acquisition on Zynq boards are presented. This methodology considerably reduces the development time and effort of power electronics solutions using Zynq-based boards. In addition, a demonstration Simulink model is provided with all proposed techniques and protections, for use with a readily available development board (Zedboard) and ADC modules. This should further reduce the learning curve and development effort of this type of solution, contributing to a broader access to high-performance control prototyping using Zynq-based platforms. An application example is presented to demonstrate the potential of the proposed workflow, using a Zedboard to control a multilevel UPS inverter prototype with Model Predictive Control.

multi-principal element alloys, directed energy deposition, laser metal deposition, grains, crack formation, melt pool, and Technology

As efforts associated with the exploration of multi-principal element alloys (MPEAs) using computational and data-intensive methods continue to rise, experimental realization and validation of the predicted material properties require high-throughput and combinatorial synthesis of these alloys. While additive manufacturing (AM) has emerged as the leading pathway to address these challenges and for rapid prototyping through part fabrication, extensive research on developing and understanding the process-structure-property correlations is imminent. In particular, directed energy deposition (DED) based AM of MPEAs holds great promise because of the boundless compositional variations possible for functionally graded component manufacturing as well as surface cladding. We analyze the recent efforts in DED of MPEAs, the microstructural evolution during the laser metal deposition of various transition and refractory elements, and assess the effects of various processing parameters on the material phase and properties. Our efforts suggest that the development of robust predictive approaches for process parameter selection and modifying the synthesis mechanisms are essential to enable DED platforms to repeatedly produce defect free, stable and designer MPEAs.

on-farm experiment, collective learning, participatory research, basket of options, farmers' criteria, farming system typology, Nutrition. Foods and food supply, TX341-641, Food processing and manufacture, and TP368-456

Designing innovative cropping systems is an active field of agricultural research challenged by the agroecological transition. One of the challenges is to adapt cropping systems to the diversity of farms and contexts. For instance, in the cotton production zone of Burkina Faso differences between farm resources, agricultural situations and agronomic constraints have resulted in a wide range of farming systems. In this context, to break with the trend toward cotton production, we co-designed eight legume-based innovative cropping systems (ICS) likely to meet the objectives sought and the constraints faced by a wide range of local farmers, thus constituting a “basket of options”. Our approach was to enable each farmer to choose the option they considered best suited to their conditions. To that end, the ICSs were implemented and discussed with farmers in participatory prototyping trials. After one season of co-evaluating the different ICSs, the farmers taking part in the co-evaluation were able to test an ICS on their own farm, by choosing and adapting one of the options. Thirty-nine farmers out of seventy-three chose an ICS to test. They were asked the reasons for their choice. Their selection criteria were analyzed in relation to comments made during collective activities organized in the participatory prototyping trials. To complete this analysis, we built an expert-based farming system typology and a statistical typology based on data collected in a rural household multi-indicator survey (RHoMIS) of 63 farms participating in this study. The two farming system typologies were compared, and the relationships between farming system types and the ICS tested on the farm were analyzed. We found that farmers did not really base their choice on their farming system. Rather, they used a wide range of criteria that varied from farmer to farmer, and they were influenced by what they had learned during the collective activities organized in the participatory prototyping trials.

Vibration isolation, Sensitive experiments, Spring-damper, Prototyping, Science (General), and Q1-390

Mechanical vibrations greatly influence sensitive instruments and experiments, yet they are unavoidable. Commercial solutions that mitigate the transfer of mechanical vibrations into experiments and instruments are often associated with high prices and big footprints and are not readily available for low investment explorative testing, experimenting, and prototyping. In this paper, an open-source design for a vibration isolation chamber is presented that is constructed from readily available components and hardware such as off-the-shelf furniture and honey. An extensive guide on how to construct the simple spring-damper-based passive vibration isolation chamber is presented, and its performance is validated using a high-precision seismic accelerometer. The vibration isolation system consists of steel springs and dashpots made of steel spheres suspended in high viscosity honey. The system resonates at 1.2 Hz and successfully mitigates the transfer of vibrations of frequencies determined to be of critical interest in the 5–20 Hz range. The well-performing system has proven to be an invaluable asset in the laboratory toolbox when sensitive experiments are carried out and has already been used in a multitude of projects. The design is shared so that others may also benefit from this tool.

3D printing, Anaerobic, Probiotics, In vitro dissolution model, Oral drug delivery, Rapid prototyping, Science (General), and Q1-390

In vitro release and dissolution models are widely used in the development phases of oral drug delivery systems to measure how an active pharmaceutical ingredient (API) is released from a dosage form. However, additional requirements for these models arise when evaluating probiotic dosage forms since they are often sensitive to temperature and oxygen levels. As a solution to this, we propose a custom-designed anaerobic in vitro release setup, made mainly by 3D printing and laser cutting, to function together with state-of-the-art pharmaceutical dissolution equipment – in this case, a microDISS Profiler™. The in vitro release model makes it possible to study the release rate of oxygen-sensitive probiotics in simulated intestinal conditions, while ensuring their survival due to the anaerobic conditions. This has not been possible so far since the available in vitro dissolution models have not been compatible with anaerobic conditions. With two different case studies, the developed model combined with a microDISS Profiler™ has proven capable of measuring the release of a probiotic and a small-molecule API from microdevices for oral drug delivery. Further, the model facilitated the survival of anaerobic bacteria present in the release medium.

Ultraviolet germicidal irradiation (UVGI) lights, Indoor air quality (IAQ), Dehumidification, Reduce fungi, Science (General), and Q1-390

Many New Zealand residential dwellings suffer from dampness and fungi during the winter, which can cause respiratory health problems. This can be due to poor insulation and ventilation, and the situation worsens when residents cannot afford to heat the dwelling. The main aim of this paper is to modify an existing dehumidifier so that it can remove moisture, heat the living space and reduce fungi growth and bacteria. To achieve that, we installed ultraviolet germicidal lights (UVGI) in an existing dehumidifier with a total cost of USD $150.7 (NZD $213.76). The UVGI lights are known to be efficient in destroying the DNA of fungi and bacteria. The results show that the device reduced the fungi growth and did increase the room temperature because the dehumidifier captured two litres of water over 24 h of testing. The proposed device did achieve a reduction in particulate matters, from 0.9 μg/m3 to 0.14 μg/m3 and an acceptable range of relative humidity below 50%, which reduces the favourable conditions for fungi growth. Therefore, our proposed low-cost device does improve the indoor air quality (IAQ) in the living space.

Service composition, Semantic web services, RDF, OpenAPI Specification, Semantic ontology, Computer engineering. Computer hardware, TK7885-7895, Information technology, T58.5-58.64, Electronic computers. Computer science, and QA75.5-76.95

Abstract Web services are provided with documents that at the very least specify the endpoint, input parameters, and output or response of each operation to expose their capabilities. This should be considered through an understandable format for humans and/or machines. In the Representational State Transfer (REST) architectural style, the OpenAPI Specification (OAS) is used as a reference to create web service descriptions. However, it only supports syntactic interoperability, leading to the incapability of supporting the automated selection process. To overcome this, OAS documents must be enhanced by including semantics to each resource to provide “understandable” services. Therefore, this study aims to develop a system capable of transforming resources in OAS documents into RDF-based semantic web services. To begin, a relational database schema based on the OAS structure is created to store all objects in the OAS document. The published open-linked vocabulary was then used to create the ontology, which maps resources and their relationships on the RDF data model. To build RDF-based semantic web services, R2RML was used to generate the relational database model into triple RDF. The proposed system was also tested through prototyping and using a dataset of 106 OAS documents, which were downloaded from APIs.guru between 5–10 May 2021. The number of triple RDFs generated per document varied with resource rate. An OAS document generates 36 to 16,505 triple RDF in a dataset. The end product was a triple RDF knowledge base maintained by a graph management database. It is now possible to find service operations, input and output parameters, and service composition requirements utilizing the repository semantic web services using SPARQL. On the other hand, the use of relational databases to store OAS resources increased reuse efficiency by approximately 48%, owing to service developers designing interoperability between uniform parameter services, which were then used as input and output.

Fused deposition modeling (FDM), Fiber bragg-grating (FBG) sensor, Earth pressure, Water pressure, Engineering geology. Rock mechanics. Soil mechanics. Underground construction, and TA703-712

A novel fiber Bragg grating (FBG) sensor with three-dimensional (3D) fused deposition modeling (FDM) approach is proposed for effective stress measurement in soil mass. The three-diaphragm structure design is developed to measure earth and water pressures simultaneously. The proposed transducer has advantages of small size, high sensitivity, low cost, immunity to electromagnetic interference and rapid prototyping. The working principle, design parameters, and manufacturing details are discussed. The proposed transducer was calibrated for earth and water pressures measurement by using weights and a specially designed pressure chamber, respectively. The calibration results showed that the wavelength of the transducer was proportional to the applied pressure. The sensitivity coefficients of the earth and water pressures were 12.633 nm/MPa and 6.282 nm/MPa, respectively. Repeated tests and error analysis demonstrated the excellent stability and accuracy of the earth and water pressure measurements. The performance of the proposed transducer was further verified by a model experimental test and numerical analysis, which indicated that the proposed transducer has great potential for practical applications.

gear system, vibration control, vibration absorber, internal resonance, Mechanical engineering and machinery, and TJ1-1570

The gear system is one of the most widely-used transmission systems due to its accurate transmission ratio and high efficiency. However, torsional vibration may severely degrade transmission performance and shorten the gear lifespan. In view of this, a nonlinear interaction principle suitable for vibration energy transfer is researched, and an internal resonance based method is put forward to reduce the torsional vibration of the gear system. According to the coupling relationship between the gear torsional vibration mode and the vibration absorber mode, the 1:1 internal resonance condition is analyzed by the multiple scale method and the sufficient and necessary conditions for establishing internal resonance are obtained. Through stability analysis, the vibration energy transfer channel based on internal resonance is successfully established, by which vibration energy can be transferred to and dissipated by the vibration absorber. Based on numerical and virtual prototyping simulations, vibration reduction performances are examined, including effectiveness, damping characteristics and robustness. The research results show that the proposed internal resonance based method can effectively reduce the torsional vibration of the gear system.

flexible manipulator, primary resonance, saturation control, Mechanical engineering and machinery, and TJ1-1570

When primary resonance occurs, even a small external disturbance can abruptly excite large amplitude vibration and deteriorate the working performance of a flexible manipulator. Most active control methods are effective for non-resonant vibration but not for primary resonance. In view of this, this paper puts forward a new nonlinear saturation-based control method to suppress the primary resonance of a flexible manipulator considering complicated rigid-flexible coupling and modal coupling. A vibration absorber with variable stiffness/damping is designed to establish an energy exchange channel for saturation. A novel idea of modal coupling enhancement is suggested to improve saturation performance by strengthening the coupling relationship between the mode of the vibration absorber and the controlled mode of the flexible manipulator. Through stability analysis on the primary resonance response of the flexible manipulator with the vibration absorber, the saturation mechanism is successfully established and the effectiveness of the saturation control algorithm is validated. On this basis, several important indexes are extracted and employed to optimize saturation control. Finally, a series of virtual prototyping simulations and experiments are conducted to verify the feasibility of the suggested saturation-based control method. This research will contribute to the primary resonance suppression of a flexible manipulator under a complex external excitation environment.

integrated optics, photonic chips, femtosecond laser fabrication, optical communications, Mechanical engineering and machinery, and TJ1-1570

Integrated optics, having the unique properties of small size, low loss, high integration, and high scalability, is attracting considerable attention and has found many applications in optical communications, fulfilling the requirements for the ever-growing information rate and complexity in modern optical communication systems. Femtosecond laser fabrication is an acknowledged technique for producing integrated photonic devices with unique features, such as three-dimensional fabrication geometry, rapid prototyping, and single-step fabrication. Thus, plenty of femtosecond laser-fabricated on-chip devices have been manufactured to realize various optical communication functions, such as laser generation, laser amplification, laser modulation, frequency conversion, multi-dimensional multiplexing, and photonic wire bonding. In this paper, we review some of the most relevant research progress in femtosecond laser-fabricated photonic chips for optical communications, which may break new ground in this area. First, the basic principle of femtosecond laser fabrication and different types of laser-inscribed waveguides are briefly introduced. The devices are organized into two categories: active devices and passive devices. In the former category, waveguide lasers, amplifiers, electric-optic modulators, and frequency converters are reviewed, while in the latter, polarization multiplexers, mode multiplexers, and fan-in/fan-out devices are discussed. Later, photonic wire bonding is also introduced. Finally, conclusions and prospects in this field are also discussed.

additive manufacturing, 3D-Printing, rapid prototyping, FFF, SSE, personalized therapy, Organic chemistry, and QD241-441

Novel additive manufacturing (AM) techniques and particularly 3D printing (3DP) have achieved a decade of success in pharmaceutical and biomedical fields. Highly innovative personalized therapeutical solutions may be designed and manufactured through a layer-by-layer approach starting from a digital model realized according to the needs of a specific patient or a patient group. The combination of patient-tailored drug dose, dosage, or diagnostic form (shape and size) and drug release adjustment has the potential to ensure the optimal patient therapy. Among the different 3D printing techniques, extrusion-based technologies, such as fused filament fabrication (FFF) and semi solid extrusion (SSE), are the most investigated for their high versatility, precision, feasibility, and cheapness. This review provides an overview on different 3DP techniques to produce personalized drug delivery systems and medical devices, highlighting, for each method, the critical printing process parameters, the main starting materials, as well as advantages and limitations. Furthermore, the recent developments of fused filament fabrication and semi solid extrusion 3DP are discussed. In this regard, the current state of the art, based on a detailed literature survey of the different 3D products printed via extrusion-based techniques, envisioning future directions in the clinical applications and diffusion of such systems, is summarized.

3D printing, polymer texture printing, polymer morphology, crystal orientation, mechanical properties, Organic chemistry, and QD241-441

Direct digital manufacturing consists of a set of techniques that enable products to be fabricated directly from their digital definition, without the use of complex tooling or moulds. This manufacturing approach streamlines prototyping and small-scale production, as well as the mass customization of parts with complex designs immediately fixed before fabrication. With broad applicability, there are clearly opportunities in the field of medical devices for its use. However, many of the developments of direct digital manufacturing focus on simply specifying the shape or the form of the product, and this limited scope throws away many of the particular advantages of direct digital manufacturing. This work is focused on remedying this situation so that the digital specification of the fabricated product includes the properties as well as the form of the product. We use in situ time-resolving small-angle X-ray scattering measurements performed at the ALBA Synchrotron Light Source in Barcelona to evaluate the control that can be exerted on the morphology of a semi-crystalline polymer during extruder-based 3D printing. We use this as a methodology for printing the patterns of the morphology of the polymer to realise the patterns of properties of the polymeric material, specifically the modulus of the polymer. We give an example of products produced in this manner that contain spatial variation in their properties.

snake robot, series elastic actuator, SEA, robotics, Mechanical engineering and machinery, and TJ1-1570

The term perception-driven obstacle-aided locomotion (POAL) was proposed to describe locomotion in which a snake robot leverages a sensory-perceptual system to exploit the surrounding operational environment and to identify walls, obstacles, or other structures as a means of propulsion. To attain POAL from a control standpoint, the accurate identification of push-points and reliable determination of feasible contact reaction forces are required. This is difficult to achieve with rigidly actuated robots because of the lack of compliance. As a possible solution to this challenge, our research group recently presented Serpens, a low-cost, open-source, and highly compliant multi-purpose modular snake robot with a series elastic actuator (SEA). In this paper, we propose a new prototyping iteration for our snake robot to achieve a more dependable design. The following three contributions are outlined in this work as a whole: the remodelling of the elastic joint with the addition of a damper element; a refreshed design for the screw-less assembly mechanism that can now withstand higher transverse forces; the re-design of the joint module with an improved reorganisation of the internal hardware components to facilitate heat dissipation and to accommodate a larger battery with easier access. The Robot Operating System (ROS) serves as the foundation for the software architecture. The possibility of applying machine learning approaches is considered. The results of preliminary simulations are provided.

audiences, audio, bbc radiophonic workshop, echo, exhibition prototyping, listening, national science and media museum, sound, sound archives, sound postcards, sound technology, History of scholarship and learning. The humanities, AZ20-999, Museums. Collectors and collecting, and AM1-501

This article reports on the experimental methodology and key findings of the AHRC-funded impact and engagement project Sonic Futures: Collecting, Curating and Engaging with Sound at the National Science and Media Museum (2020–21). The project undertook a series of listening-based public engagement activities – described here as staging listening – to identify new ways of engaging listening audiences with sound technology objects in museums. These activities led to the creation of three new interactive sounding exhibit prototypes created jointly with audiences. Because the project took place during periods of lockdown caused by the coronavirus pandemic in the UK in 2020–21, the exhibit prototypes were created digitally and tested via online interaction. The article argues that engaging with listening audiences can diversify and enrich museum listening scenarios, a term we use here to describe auditory situations which elicit different kinds of listening attention, interaction and learning. These listening scenarios produce divergent signatures of listening, a concept we develop here to describe the various kinds of learning and engagement we observed throughout the project.

Medicine and Science

Abstract Microwave undulators (MUs) have great potential to be an alternative solution to permanent magnet undulators in a free electron laser (FEL) when shorter undulator periods are required. In this paper, the factors that affect the choice of the high-power drive sources were studied via a Ka-band cavity-type MU with a corrugated waveguide proposed for the CompactLight X-ray FEL. They include the technology of the high-power vacuum electronic devices, the quality factor of the MU cavity that was demonstrated by prototyping a short section of the MU structure, and the beam dynamic study of the electrons’ trajectories inside the MU. It showed that at high beam energy, a high-power oscillator is feasible to be used as the drive source. At low beam energy, the maximum transverse drift distance becomes larger therefore an amplifier has to be used to minimize the drift distance of the electrons by controlling the injection phase.

Generation Y Office Workers, Interaction Qualities, Interactive Prototyping, User Evaluation, Computer engineering. Computer hardware, and TK7885-7895

Background: With more and more products becoming digital, mobile, and networked, paying attention to the qualities of interactions with is also getting more relevant. While interaction qualities have been addressed in several scientific studies, little attention is being paid to their implementation into a real life, everyday context. This paper describes the development of a novel office phone prototype, YPhone, which demonstrates the application of a specific set of Generation Y interaction qualities (instant, playful, collaborative, expressive, responsive, and flexible) into the context of office work. The working prototype supports office workers in experiencing new type of interactions. It is set out in practice in a series of evaluations. We found that the playful, expressive, responsive, and flexible qualities have more trust than the instant and collaborative qualities. Qualities can be grouped, although this may be different for different products that are evaluated, so researchers must be cautious about generalizing. The overall evaluation was positive with some valuable suggestions to its user interactions and features.

soft robotics, soft pneumatic actuators, soft components, control systems, prototyping, Materials of engineering and construction. Mechanics of materials, TA401-492, Production of electric energy or power. Powerplants. Central stations, and TK1001-1841

In the field of robotics, soft robots have been showing great potential in the areas of medical care, education, service, rescue, exploration, detection, and wearable devices due to their inherently high flexibility, good compliance, excellent adaptability, and natural and safe interactivity. Pneumatic soft robots occupy an essential position among soft robots because of their features such as lightweight, high efficiency, non-pollution, and environmental adaptability. Thanks to its mentioned benefits, increasing research interests have been attracted to the development of novel types of pneumatic soft robots in the last decades. This article aims to investigate the solutions to develop and research the pneumatic soft robot. This paper reviews the status and the main progress of the recent research on pneumatic soft robots. Furthermore, a discussion about the challenges and benefits of the recent advancement of the pneumatic soft robot is provided.

Physics and QC1-999

A two-channel prototype cryogenic temperature transmitter is developed using an ARM Cortex-M3 series precision analog microcontroller using a rapid prototyping method for use in indigenous developments. The developed prototype utilizes an Arduino compatible baseboard equipped with interfaces for programming/debugging. Additional circuits are fabricated, and embedded application software is developed and tested. The input circuit consists of a low-value high accuracy precision current source to excite the cryogenic temperature sensors of Resistance Temperature Detector (RTD) type and employs a standard four-wire ratiometric measurement technique for accurate resistance measurement. The ratiometric measurement eliminates measurement errors due to current uncertainty. The precision microcontroller is equipped with internal programmable gain amplifiers to accurately scale low-level analog signals from cryogenic temperature sensors. The developed transmitter can interface with two cryogenic RTDs (Cernox® and PT-100 types) and can accurately measure resistance over its calibrated range (300–4 K). The cubic spline interpolation method is employed in application software for converting the measured resistance to temperature. The measured temperature is transmitted to a programmable logic device (via 4–20 mA signals) using the pulse width modulation technique. The developed transmitter is tested for its performance against commercially available transmitters at the liquid nitrogen temperature, liquid helium temperature, and over the entire measurement range using Gifford–McMahon type cryocoolers. The developed transmitter was utilized to assess the impact of the thermal resistance of the cryogenic sensors at the lowest temperature of the cryocooler (∼2.6 K). This paper outlines design details, application software development, experimental setup, measurement uncertainties, and test results.

virtual commissioning, robotic cell, RobotStudio, virtual prototyping, TwinCAT, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, and QD1-999

Intelligent robotic manufacturing cells must adapt to ever-varying operating conditions, developing autonomously optimal manufacturing strategies to achieve the best quality and overall productivity. Intelligent and cognitive behaviors are realized by using distributed controllers, in which complex control logics must interact and process a wide variety of input/output signals. In particular, programmable logic controllers (PLCs) and robot controllers must be coordinated and integrated. Then, there is the need to simulate the robotic cells’ behavior for performance verification and optimization by evaluating the effects of both PLC and robot control codes. In this context, this work proposes a method, and its implementation into an integrated tool, to exploit the potential of ABB RobotStudio software as a virtual prototyping platform for robotic cells, in which real robots control codes are executed on a virtual controller and integrated with Beckhoff PLC environment. For this purpose, a PLC Smart Component was conceived as an extension of RobotStudio functionalities to exchange signals with a TwinCAT instance. The new module allows the virtual commissioning of a complete robotic cell to be performed, assessing the control logics effects on the overall productivity. The solution is demonstrated on a robotic assembly cell, showing its feasibility and effectiveness in optimizing the final performance.

clinical trial, heuristics, management, mobile application, technology, telemedicine, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, and QD1-999

Wearable devices and digital health technologies have enabled the exchange of urgent clinical trial information. We developed an application to improve the functioning of decentralized clinical trials and performed a heuristic evaluation to reflect the user demands of existing clinical trial workers. The waterfall model of the software life cycle was used to guide the development. Focus group interviews (N = 7) were conducted to reflect the needs of clinical research professionals, and Wizard of Oz prototyping was performed to ensure high usability and completeness. Unit tests and heuristic evaluation (N = 11) were used. Thematic analysis was performed using the focus group interview data. Based on this analysis, the main menu was designed to include health management, laboratory test results, medications, concomitant medications, adverse reactions, questionnaires, meals, and My Alarm. Through role-playing, the functions and configuration of the prototype were adjusted and enhanced, and a heuristic evaluation was performed. None of the heuristic evaluation items indicated critical usability errors, suggesting that the revised prototype application can be practically applied to clinical trials. The application is expected to increase the efficiency of clinical trial management, and the development process introduced in this study will be helpful for researchers developing similar applications in the future.

Cell-free protein synthesis, Protein biomaterials, Supramolecular assembly, Technology, Chemical technology, TP1-1185, Biotechnology, and TP248.13-248.65

Abstract Protein-based biomaterials have the characteristics of stability and biocompatibility. Based on these advantages, various bionic materials have been manufactured and used in different fields. However, current protein-based biomaterials generally need to form monomers in cells and be purified before being assembled in vitro. The preparation process takes a long time, and the complex cellular environment is challenging to be optimized for producing the target protein product. Here this study proposed technology for in situ synthesis and assembly of the target protein, namely the cell-free protein synthesis (CFPS), which allowed to shorten the synthesis time and increase the flexibility of adding or removing natural or synthetic components. In this study, successful expression and self-assembly of the dihedral symmetric proteins proved the applicability of the CFPS system for biomaterials production. Furthermore, the fusion of different functional proteins to these six scaffold proteins could form active polymers in the CFPS system. Given the flexibility, CFPS is expected to become a powerful tool as the prototyping and manufacturing technology for protein-based biomaterials in the future. Graphical Abstract

Online learning, Mobile health, Primary health care, Health workers, Infection prevention and control, Nigeria, Public aspects of medicine, and RA1-1270

Abstract Background Health workers (HWs) in Africa face challenges accessing and learning from existing online training opportunities. To address these challenges, we developed a modular, self-paced, mobile-ready and work-relevant online course covering foundational infection prevention and control (IPC) concepts. Here, we evaluate the first pilot of this course, conducted with HWs in Nigeria. Methods We used a learner-centered design and prototyping process to create a new approach to delivering online training for HWs. The resulting course comprised 10 self-paced modules optimized for use on mobile devices. Modules presented IPC vignettes in which learning was driven by short assessment questions with feedback. Learners were recruited by distributing a link to the training through Nigeria-based email lists, WhatsApp groups and similar networks of HWs, managers and allied professionals. The course was open to learners for 8 weeks. We tracked question responses and time on task with platform analytics and assessed learning gains with pre- and post-testing. Significance was evaluated with the Wilcoxon signed-rank test, and effect size was calculated using Cohen’s d. Results Three hundred seventy-two learners, with roles across the health system, enrolled in the training; 59% completed all 10 modules and earned a certificate. Baseline knowledge of foundational IPC concepts was low, as measured by pre-test scores (29%). Post-test scores were significantly higher at 54% (effect size 1.22, 95% confidence interval 1.00-1.44). Learning gains were significant both among learners with low pre-test scores and among those who scored higher on the pre-test. We used the Net Promoter Score (NPS), a common user experience metric, to evaluate the training. The NPS was + 62, which is slightly higher than published scores of other self-paced online learning experiences. Conclusions High completion rates, significant learning gains and positive feedback indicate that self-paced, mobile-ready training that emphasizes short, low-stakes assessment questions can be an effective, scalable way to train HWs who choose to enroll. Low pre-test scores suggest that there are gaps in IPC knowledge among this learner population.

policy design, design thinking, policy implementation, reshoring, policy prototyping, Technology (General), T1-995, Technological innovations. Automation, and HD45-45.2

Design for policy deals with the policy cycle by recurring to design practices and tools, such as user-centered design, co-design, insights identification, abduction, creativity, prototyping. Empirical studies show that practice of design as inspirational and creative practice usually happens in the first phases of the policy cycle, and it hardly manages the challenges faced in policy formulation and policy implementation of the later phases of the policy cycle. In this case study we experiment with a policy innovation process that deals with those practices also in later stages of the policy cycle. The case study settles at the Regional level in Emilia Romagna to foster Reshoring initiatives.

ultra-thin-chips, multi-project wafers, hybrid integration, thermoconic flip chip, anisotropic conductive adhesives, flexible electronics, Electronics, and TK7800-8360

Die-level thinning, handling, and integration of singulated dies from multi-project wafers (MPW) are often used in research, early-stage development, and prototyping of flexible devices. There is a high demand for thin silicon devices for several applications, such as flexible electronics. To address this demand, we study a novel post-processing method on two silicon devices, an electrochemical impedance sensor, and Complementary Metal Oxide Semiconductor (CMOS) die. Both are drawn from an MPW batch, thinned at die-level after dicing and singulation down to 60 µm. The thinned dies were flip-chip bonded to flexible substrates and hermetically sealed by two techniques: thermosonic bonding of Au stud bumps and anisotropic conductive paste (ACP) bonding. The performance of the thinned dies was assessed via functional tests and compared to the original dies. Furthermore, the long-term reliability of the flip-chip bonded thinned sensors was demonstrated to be higher than the conventional wire-bonded sensors.

hybrid-electric ship, hybrid-electric propulsion system, hybrid-electric vehicle, electric propulsion ship, shipboard power system, electric naval propulsion, and Technology

International maritime transport organizations are proposing regulatory actions and strategies aimed at decarbonizing the sector to reduce its greenhouse gas (GHG) emissions, which currently constitute around 3% of the global total. Hybrid propulsion systems have significant potential in this respect, as a means of power-saving in ships. This paper describes a high-fidelity benchmark for hybrid-electric vessels, combining diesel generators and batteries. The benchmark consists of detailed models, the parameters of which are provided so that the models can be reproduced. The proposed hybrid-electric ship topology and control system was validated using real-time hardware-in-the-loop (HIL) simulations on a Typhoon HIL402 platform. The results provide a detailed analysis of the operation of the different components under varying conditions, which should be useful in prototyping these kinds of systems. In addition, the response of the system was evaluated with regard to potential disturbances resulting from the control system’s operation. The results show the system performed correctly during these transitory events, with no undesirable responses.

regulations, socioeconomic, organizations, barriers, data-driven, and Technology

Data-driven services offer a major shift away from traditional monitoring and control approaches that have been applied exclusively over the transmission and distribution networks. These services assist the electricity value chain stakeholders to enhance their data reach and improve their internal intelligence on electricity-related optimization functions. However, the penetration of data-driven services within the energy sector poses challenges across the regulatory, socioeconomic, and organizational (RSEO) domains that are specific to such business models. The present review examines the existence and importance of various obstacles across these domains regarding innovative energy services, new business models, data exchanges, and other actors’ synergies across the electricity data value chain. This research is centered around the European landscape, with a particular focus on the five demonstration countries (Greece, Spain, Austria, Finland, and Croatia) of the SYNERGY consortium. A state-of-the-art analysis on the regulatory, socioeconomic, and organizational aspects related to innovative energy services (IESs) revealed a plethora of such potential obstacles that could affect, in various degrees, the realization of such services, both at a prototyping and a market replication level. More specifically, 13 barriers were identified in the regulatory domain, 19 barriers were identified in the socioeconomic domain, and 16 barriers were identified in the organizational domain. Then, a comprehensive, survey-based data gathering exercise was designed, formulated, and conducted at a national level as well as at a stakeholder type level. To ensure that our analysis encompassed business-wide perspectives and was validated from the whole electricity data value chain, we utilized a trilevel analysis (i.e., partner, stakeholder type, demo country) to formulate qualitative interviews with business experts from each stakeholder type (namely TSOs, DSOs, aggregators/ESCOs, facility managers/urban planners, and RES Operators). By combining the quantitative data with the qualitative interviews, further recommendations on identifying and facilitating ways to overcome the identified barriers are provided. For the regulatory domain, it is recommended to treat nationally missing regulations by conforming to the provisions of the relevant EU directives, as well as to provide a flexibility-related regulation. For the socioeconomic domain, recommendations were made to increase consumer awareness and thus alleviate the three more impactful barriers identified in this domain. All organizational barriers can be alleviated by taking complex big-data-related issues away from the hands of the organizations and offering them data-as-a-service mechanisms that safeguard data confidentiality and increase data quality.

discrete-time control, harmonics, grid-connected inverter, modeling, voltage source converter, and Technology

This paper elaborates on a development technique for the grid-connected voltage source converter (VSC). We propose a simulation technique in the MATLAB/Simulink environment that emulates the operation of the discrete-time controlled grid-connected VSC. The switched-circuit modeling approach is used for simulation of the power stage in the continuous-time domain with the physical unit scale. The discrete-time control algorithm is implemented in an interpreted MATLAB function in the per-unit scale, which synchronizes with the switching period. Such a control algorithm is easily translated into the C language for programing of the 32-bit C2000 DSP controller with the same regulators’ parameters. The proposed platform was validated with a hardware-in-the-loop real-time simulator and with a 5-kVA 3-phase LCL-filtered grid-connected VSC. The discrete-time control scheme was implemented in the synchronous reference frame control with proportional-integral with multi-resonant controllers at harmonic orders 6th and 12th for suppression of the grid voltage harmonic orders 5th, 7th, 11th, and 13th. The experimental results closely agreed with the simulation results. The experimental grid currents complied with the IEEE 1547 standard thanks to the multi-resonant controllers. The proposed platform provides a smooth transition from implementation to a near-commercial prototype with a low investment cost in simulation and rapid prototyping tools. A MATLAB/Simulink VSC model is provided as an attachment of this paper.

automated driving, driver assistance system, virtual test and validation, radar sensor, physical perception model, virtual sensor model, and Technology

In recent years, verification and validation processes of automated driving systems have been increasingly moved to virtual simulation, as this allows for rapid prototyping and the use of a multitude of testing scenarios compared to on-road testing. However, in order to support future approval procedures for automated driving functions with virtual simulations, the models used for this purpose must be sufficiently accurate to be able to test the driving functions implemented in the complete vehicle model. In recent years, the modelling of environment sensor technology has gained particular interest, since it can be used to validate the object detection and fusion algorithms in Model-in-the-Loop testing. In this paper, a practical process is developed to enable a systematic evaluation for perception–sensor models on a low-level data basis. The validation framework includes, first, the execution of test drive runs on a closed highway; secondly, the re-simulation of these test drives in a precise digital twin; and thirdly, the comparison of measured and simulated perception sensor output with statistical metrics. To demonstrate the practical feasibility, a commercial radar-sensor model (the ray-tracing based RSI radar model from IPG) was validated using a real radar sensor (ARS-308 radar sensor from Continental). The simulation was set up in the simulation environment IPG CarMaker® 8.1.1, and the evaluation was then performed using the software package Mathworks MATLAB®. Real and virtual sensor output data on a low-level data basis were used, which thus enables the benchmark. We developed metrics for the evaluation, and these were quantified using statistical analysis.

Mobile applications, Vancomycin, Drug dosage calculation, Methicillin-resistant Staphylococcus aureus, Pharmacy and materia medica, and RS1-441

Background: Mobile applications (app) provide many benefits for healthcare professionals, making them a useful support clinical decision system. Objectives: To describe the development of a mobile app, CalcVAN, to calculate vancomycin dosage regimens for adult and pediatric patients. Methods: This study is a technological production research to develop a mobile app through the rapid prototyping type for the Android system in the Brazilian context. The mobile app structure was developed in four steps: 1) conception, including the needs assessment, the target audience, the literature search, and the definition of contents; 2) prototype planning, including the definition of topics and writing of modules, the selection of media, and the layout; 3) production of the mobile app, including the selection of multimedia tools, the navigation structure, and planning of environment configuration; and 4) make the mobile app available. Results: The CalcVAN has six screens, containing the vancomycin dosing calculator for adult and pediatric patients based on weight and estimated creatinine clearance parameters. Moreover, the mobile app is free and can be used without internet connection. Conclusions: A free mobile app was developed to calculate vancomycin dosage regimens for inpatients. This tool assists to optimize the vancomycin dosing, contributing to the antimicrobial stewardship.

wearable device, exoskeleton, differential mechanism, prototyping, rehabilitation, Mechanical engineering and machinery, TJ1-1570, Electronic computers. Computer science, and QA75.5-76.95

Exoskeletons and more in general wearable mechatronic devices represent a promising opportunity for rehabilitation and assistance to people presenting with temporary and/or permanent diseases. However, there are still some limits in the diffusion of robotic technologies for neuro-rehabilitation, notwithstanding their technological developments and evidence of clinical effectiveness. One of the main bottlenecks that constrain the complexity, weight, and costs of exoskeletons is represented by the actuators. This problem is particularly evident in devices designed for the upper limb, and in particular for the hand, in which dimension limits and kinematics complexity are particularly challenging. This study presents the design and prototyping of a hand finger exoskeleton. In particular, we focus on the design of a gear-based differential mechanism aimed at coupling the motion of two adjacent fingers and limiting the complexity and costs of the system. The exoskeleton is able to actuate the flexion/extension motion of the fingers and apply bidirectional forces, that is, it is able to both open and close the fingers. The kinematic structure of the finger actuation system has the peculiarity to present three DoFs when the exoskeleton is not worn and one DoF when it is worn, allowing better adaptability and higher wearability. The design of the gear-based differential is inspired by the mechanism widely used in the automotive field; it allows actuating two fingers with one actuator only, keeping their movements independent.

additive manufacturing, reusable launch vehicle, computational fluid dynamics, shock waves, Motor vehicles. Aeronautics. Astronautics, and TL1-4050

Computational fluid dynamics and Additive manufacturing are the two important and recently used technique in the reusable launch vehicle. In this article the design and flow simulation of the re-entry capsule has been performed using Computational Fluid Dynamics in order to optimize the suitable re-entry capsule design. Computational fluid dynamics can be used to simulate the real time supersonic flow during re-entry which helps in predicting the important characteristics during the formation of shock waves. The study considered Mach 5 conditions and an altitude of 5km. In addition, the formation of shock waves was delayed in the present studies compared to previous work. It should be noted that the current aerospace industry uses the advantage of additive production in prototyping to test re-entry launch vehicles.

protein adsorption, antibody immobilization, hydrophobic interactions, immunosensing, Lab-on-a-Foil, printed microfluidics, Biology (General), QH301-705.5, Chemistry, and QD1-999

Laser toners appear as attractive materials for barriers and easily laminated interphases for Lab-on-a-Foil microfluidics, due to the excellent adhesion to paper and various membranes or foils. This work shows for the first time a comprehensive study on the adsorption of antibodies on toner-covered poly(ethylene terephthalate) (PET@toner) substrates, together with assessment of such platforms in rapid prototyping of disposable microdevices and microarrays for immunodiagnostics. In the framework of presented research, the surface properties and antibody binding capacity of PET substrates with varying levels of toner coverage (0–100%) were characterized in detail. It was proven that polystyrene-acrylate copolymer-based toner offers higher antibody adsorption efficiency compared with unmodified polystyrene and PET as well as faster adsorption kinetics. Comparative studies of the influence of pH on the effectiveness of antibodies immobilization as well as measurements of surface ζ-potential of PET, toner, and polystyrene confirmed the dominant role of hydrophobic interactions in adsorption mechanism. The applicability of PET@toner substrates as removable masks for protection of foil against permanent hydrophilization was also shown. It opens up the possibility of precise tuning of wettability and antibody binding capacity. Therefore, PET@toner foils are presented as useful platforms in the construction of immunoarrays or components of microfluidic systems.

Theory and practice of education, LB5-3640, Mathematics, and QA1-939

Abstrak. Bahan ajar yang interaktif sangat diperlukan dalam proses pembelajaran. Salah satu materi pada pembelajaran matematika yang memerlukan bahan ajar interaktif adalah bangun ruang sisi datar. Penelitian ini bertujuan untuk menghasilkan bahan ajar interaktif berbasis komputer pada materi bangun ruang sisi datar untuk kelas VIII SMP yang valid dan praktis. Penelitian ini menggunakan Development Research dengan dua tahapan, yaitu tahap preliminary dan tahap prototyping menggunakan alur formative evaluation yang terdiri dari self evaluation, expert review, one-to-one dan small group. Teknik pengumpulan data yang digunakan meliputi angket, wawancara, dan dokumentasi. Adapun instrumen yang digunakan meliputi lembar validasi dan angket kepraktisan. Subjek penelitian ini adalah siswa kelas VIII SMP . Hasil penelitian ini adalah bahan ajar berbasis komputer pada materi bangun ruang sisi datar yang tergolong valid berdasarkan lembar validasi dan komentar ahli. Validator menyimpulkan bahwa bahan ajar yang di kembangkan ini telah baik dari segi konten, desain, kualitas teknis dan menyatakan layak untuk diujicobakan. Sedangkan kepraktisan dari bahan ajar dinilai dari hasil angket respon siswa dan wawancara pada tahap one-to-one dan small group. Siswa menyatakan bahwa bahan ajar mudah digunakan, membantu siswa menguasai materi bangun ruang sisi datar, dan tertarik untuk menggunakan bahan ajar berbasis komputer. Kata Kunci: Bahan Ajar, Penelitian Pengembangan, Bangun Ruang Sisi Datar

degree of crystallinity, polyamide-6, rapid prototyping, nanocomposite, self-healing, Technology, and Science

Polymer components capable of self-healing can rapidly be manufactured by injecting the monomer (ε-caprolactam), activator and catalyst mixed with a small amount of magnetic nanoparticles into a steel mould. The anionic polymerisation of the monomer produces a polymer component capturing magnetic nanoparticles in a dispersed state. Any microcracks developed in this nanocomposite component can be healed by exposing it to an external alternating magnetic field. Due to the magnetocaloric effect, the nanoparticles locally melt the polymer in response to the magnetic field and fill the cracks, but the nanoparticles require establishing a network within the matrix of the polymer through effective dispersion for functional and uniform melting. The dispersed nanoparticles, however, affect the degree of crystallinity of the polymer depending on the radius of gyration of the polymer chain and the diameter of the magnetic nanoparticle agglomerates. The variation in the degree of crystallinity and crystallite size induced by nanoparticles can affect the melting temperature as well as its mechanical strength after testing for applications, such as stimuli-based self-healing. In the case of in situ synthesis of the polyamide-6 (PA6) magnetic nanocomposite (PMC), there is an opportunity to alter the degree of crystallinity and crystallite size by optimising the catalyst and activator concentration in the monomer. This optimisation method offers an opportunity to tune the crystallinity and, thus, the properties of PMC, which otherwise can be affected by the addition of nanoparticles. To study the effect of the concentration of the catalyst and activator on thermal properties, the degree of crystallinity and the crystallite size of the component (PMC), the ratio of activator and catalyst is varied during the anionic polymerisation of ε-caprolactam, but the concentration of Fe3O4 nanoparticles is kept constant at 1 wt%. Differential Scanning Calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR), XRD (X-ray diffraction) and Thermogravimetric analysis (TGA) were used to find the required concentration of the activator and catalyst for optimum properties. It was observed that the sample with 30% N-acetyl caprolactam (NACL) (with 50% EtMgBr) among all of the samples was most suitable to Rapid Prototype the PMC dog-bone sample with the desired degree of crystallinity and required formability.

Laser engineered net shaping, Functionally graded materials, Martensite, Austenite, Tensile properties, Thermodynamic modeling, Mining engineering. Metallurgy, and TN1-997

Laser engineered net shaping (LENS) is an advanced additive manufacturing technology combining rapid prototyping and synchronization technology. Its multi-powder feeder delivery system enables multi-materials building in single deposition, which is appropriate for additive manufacturing of functionally graded materials (FGMs). In this study, martensitic-stainless steel (MSS)/austenitic stainless steel (ASS) FGMs with composition transitioning from 100% MSS incrementally graded to 100% ASS by 25% composition gradients are fabricated by LENS. The Vickers hardness of MSS/ASS FGMs ranges from 358 to 170 HV. The decrease of hardness is found to relate to the grain-growth region with the increase of austenite. The obtained specimens of MSS/ASS FGMs show a tensile strength of 669 MPa and an elongation of 19%. In addition, the fracture location of MSS/ASS FGMs in tensile test is in the region of 100% ASS, which is dominated by austenite structure. Finally, the Scheil–Gulliver model is introduced to validate the phase formation of MSS/ASS FGMs’ failure region. Experimental and modeling results indicate that precipitation of α-ferrite in the austenite structure leads to reduced ductility of MSS/ASS FGMs.

spinal implants, pedicle guides, implants, 3D-printed, biomechanical, and Medicine

For decades, the advantages of rapid prototyping for clinical use have been recognized. However, demonstrations of potential solutions to treat spinal problems that cannot be solved otherwise are scarce. In this paper, we describe the development, regulatory process, and clinical application of two types of patient specific 3D-printed devices that were developed at an in-house 3D point-of-care facility. This 3D lab made it possible to elegantly treat patients with spinal problems that could not have been treated in a conventional manner. The first device, applied in three patients, is a printed nylon drill guide, with such accuracy that it can be used for insertion of cervical pedicle screws in very young children, which has been applied even in semi-acute settings. The other is a 3D-printed titanium spinal column prosthesis that was used to treat progressive and severe deformities due to lysis of the anterior column in three patients. The unique opportunity to control size, shape, and material characteristics allowed a relatively easy solution for these patients, who were developing paraplegia. In this paper, we discuss the pathway toward the design and final application, including technical file creation for dossier building and challenges within a point-of-care lab.

fel physics, instrumentation, microfluidics, liquid jets, high-viscosity extrusion, aerosols, rapid mixing, sample delivery, x-ray scattering, crystallography, single-particle imaging, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798, Crystallography, and QD901-999

The Sample Environment and Characterization (SEC) group of the European X-ray Free-Electron Laser (EuXFEL) develops sample delivery systems for the various scientific instruments, including systems for the injection of liquid samples that enable serial femtosecond X-ray crystallography (SFX) and single-particle imaging (SPI) experiments, among others. For rapid prototyping of various device types and materials, sub-micrometre precision 3D printers are used to address the specific experimental conditions of SFX and SPI by providing a large number of devices with reliable performance. This work presents the current pool of 3D printed liquid sample delivery devices, based on the two-photon polymerization (2PP) technique. These devices encompass gas dynamic virtual nozzles (GDVNs), mixing-GDVNs, high-viscosity extruders (HVEs) and electrospray conical capillary tips (CCTs) with highly reproducible geometric features that are suitable for time-resolved SFX and SPI experiments at XFEL facilities. Liquid sample injection setups and infrastructure on the Single Particles, Clusters, and Biomolecules and Serial Femtosecond Crystallography (SPB/SFX) instrument are described, this being the instrument which is designated for biological structure determination at the EuXFEL.

lkpd, mikir, stem, Education, Mathematics, and QA1-939

Penelitian ini bertujuan untuk melakukan pengembangan terhadap Lembar Kerja Peserta Didik (LKPD) dengan model STEM berbasis MIKiR untuk tema 2 “Selalu Berhemat Energi” pada kelas IV Sekolah Dasar dengan menggunakan model Plomp (2013). Tahapan pengembangan yang dilakukan dengan tiga fase: Preliminary Research Phase, Prototyping Phase, dan Assessment Phase. Data penelitian ini dikumpulkan dengan cara observasi, wawancara dan angket. Pengolahan data pada penelitian ini dilakukan dengan cara analisis kuantitatif deskriptif dan kualitatif deskritif. LKPD yang telah dikembangkan divalidasi oleh tiga orang ahli yang terdiri dari ahli media dan ahli materi dan memperoleh persentase skor validasri rata-rata 93,52%. Sedangkan kepraktisan dilihat dari angket respon guru dengan persentase skor rata-rata sebesar 85,99%. Maka dapat disimpulkan LKPD STEM Berbasis MIKiR yang dikembangkan valid dan praktis dan dapat digunakan dalam pembelajaran. This study aims to Development the Student Worksheet with the STEM based on MIKiR for theme 2 “Always Save Energy” in grade 4 Elementary School using the Plomp model (2013). The development stage is carried out in three stages: Preliminary Research Stage, Prototyping Stage, and Assessment Phase. The research data were collected using observation, interviews, and questionnaires. Data processing in this study was carried out using quantitative decriptive and qualitative decriptive analysis. The worksheets that were developed are validated by three experts consisting of media experts and material experts , with an avarage skore percentage is 93,52%. Meanwhile, practicality can be seen from the questionnaire responses of teachers, with an avarage skore percentage is 85,99%. In conclusion, the Student worksheet STEM based on MIKiR developed is valid and practical and can be used in learning.

lkpd, mikir, stem, Education, Mathematics, and QA1-939

Penelitian ini bertujuan untuk melakukan pengembangan terhadap Lembar Kerja Peserta Didik (LKPD) dengan pendekatan STEM berbasis MIKiR untuk materi periskop di kelas 5 Sekolah Dasar dengan menggunakan model Plomp (2013). Tahapan pengembangan yang dilakukan dengan tiga fase: Preliminary Research Phase, Prototyping Phase, dan Assessment Phase. LKPD yang telah dikembangkan divalidasi oleh tiga orang ahli yang terdiri dari ahli media dan ahli materi. Sedangkan kepraktisan dilihat dari angket respon peserta didik dan guru. Data penelitian ini dikumpulkan dengan cara observasi, wawancara dan angket. Pengolahan data pada penelitian ini dilakukan dengan cara analisis kuantitatif dan kualitatif. Hasil penelitian ini didapatkan LKPD STEM berbasis MIKiR materi periskop dinyatakan sangat valid dengan persentase rata-rata 84,06%, dan produk dinyatakan sangat praktis persentase rata-rata 92,5%. This study aims to develop a Student Worksheet with a MIKiR-based STEM approach for periscope material in grade 5 Elementary School using the Plomp model (2013). The development stage is carried out in three stages: Preliminary Research Stage, Prototyping Stage, and Assessment Stage. The student worksheets that have been developed are validated by three experts consisting of media experts and material experts. Meanwhile, practicality can be seen from the questionnaire responses of students and teachers. The research data were collected by means of observation, interviews and questionnaires. Data processing in this study was carried out by means of quantitative and qualitative analysis. The results of this study showed that the MIKiR-based LKPD STEM periscope material was declared very valid with an average percentage of 84.06%, and the product was stated to be very practical with an average percentage of 92.5%. So it can be concluded that the MIKiR-based LKPD STEM periscope material that has been developed is valid and practical and can be used in learning. Penelitian ini bertujuan untuk melakukan pengembangan terhadap Lembar Kerja Peserta Didik (LKPD) dengan pendekatan STEM berbasis MIKiR untuk materi periskop di kelas 5 Sekolah Dasar dengan menggunakan model Plomp (2013). Tahapan pengembangan yang dilakukan dengan tiga fase: Preliminary Research Phase, Prototyping Phase, dan Assessment Phase.LKPD yang telah dikembangkan divalidasi oleh tiga orang ahli yang terdiri dari ahli media dan ahli materi. Sedangkan kepraktisan dilihat dari angket respon peserta didik dan guru. Data penelitian ini dikumpulkan dengan cara observasi, wawancara dan angket. Pengolahan data pada penelitian ini dilakukan dengan cara analisis kuantitatif dan kualitatif. Hasil penelitian ini didapatkan LKPD STEM berbasis MIKiR materi periskop dinyatakan sangat valid dengan persentase rata-rata 84,06%, dan produk dinyatakan sangat praktis persentase rata-rata 92,5% . Jadi dapat disimpulkan bahwa LKPD STEM berbasis MIKiR materi periskop yang telah dikembangkan valid dan praktis serta dapat digunakan dalam pembelajaran. Kata kunci: LKPD; MIKiR; STEM Abstract This study aims to develop a Student Worksheet with a MIKiR-based STEM approach for periscope material in grade 5 Elementary School using the Plomp model (2013). The development stage is carried out in three stages: Preliminary Research Stage, Prototyping Stage, and Assessment Stage. The student worksheets that have been developed are validated by three experts consisting of media experts and material experts. Meanwhile, practicality can be seen from the questionnaire responses of students and teachers. The research data were collected by means of observation, interviews and questionnaires. Data processing in this study was carried out by means of quantitative and qualitative analysis. The results of this study showed that the MIKiR-based LKPD STEM periscope material was declared very valid with an average percentage of 84.06%, and the product was stated to be very practical with an average percentage of 92.5%. So it can be concluded that the MIKiR-based LKPD STEM periscope material that has been developed is valid and practical and can be used in learning.

Education, Mathematics, and QA1-939

Tujuan penelitian ini menghasilkan media permainan sembilun sebagai media pembelajaran literasi matematika yang valid, praktis, dan memiliki efek potensial terhadap kemampuan literasi matematika. Penelitian ini menggunakan jenis penelitian research and development (R&D) yaitu metode design research dengan siklus berulang yang menggunakan evaluasi formatif (formative evaluation). Tahap yang dilakukan pada penelitian yaitu tahap persiapan (preliminary) dan tahap prototyping (formative evaluation) yang terdiri dari one-to-one dan expert review, small group, dan field test. Penelitian dilakukan menggunakan konsep blended (daring dan luring). Teknik pengumpulan data meliputi lembar observasi, walktrough, wawancara, dan angket, serta tes langsung terkait permasalahan literasi matematika menggunakan permainan sembilun. Data dianalisis secara deskriptif kualitatif. Penelitian ini dilakukan di salah satu SMP swasta di Pangkalpinang yang melibatkan 24 siswa. Media yang telah dikembangkan dinyatakan valid berdasarkan hasil revisi dari ahli dan subjek one-to-one terkait dengan langkah-langkah permainan sembilun, aturan permainan sembilun, media permainan, dan soal literasi matematika yang digunakan. Kepraktisan terlihat dari tahap small group dimana media permainan yang dikembangkan dapat digunakan dalam pembelajaran. Efek potensial didapat pada tahap field test dimana melalui penggunaan media pembelajaran literasi matematika berbasis permainan sembilun, siswa dapat melatih kemampuan untuk merumuskan, menafsirkan, dan menerapkan konsep matematika ke dalam konteks permainan sembilun. Sehingga dapat memberikan alternatif media pembelajaran literasi matematika menggunakan permainan sembilun untuk meningkatkan kemampuan literasi matematika pada siswa Indonesia. The purpose of this study was to produce the nine game media as a valid, practical, and practical mathematical literacy learning media, and have a potential effect on mathematical literacy skills. This study uses research and development (R&D) research, namely the design research method with repeated cycles using formative evaluation. The stages carried out in the research are the preliminary stage and the prototyping stage (formative evaluation) which consist of one-to-one and expert review, small group, and field test. The research was conducted using the blended concept (online and offline). Data collection techniques include observation sheets, walkthroughs, interviews, and questionnaires, as well as direct tests related to mathematical literacy problems using the sembilun game. Data were analyzed descriptively qualitatively. This research was conducted in a private junior high school in Pangkalpinang involving 24 students. The media that has been developed is declared valid based on the revision results from experts and one-to-one subjects related to the steps of the nine games, the rules of the nine games, game media, and mathematical literacy questions used. Practicality can be seen from the small group stage where the developed game media can be used in learning. The potential effect is obtained at the field test stage where through the use of media for learning mathematics literacy based on the sembilun game, students can practice their ability to formulate, interpret, and apply mathematical concepts in the context of the sembilun game. So that it can provide an alternative media for learning mathematics literacy using the sembilun game to improve mathematical literacy skills in Indonesian students.

agricultural rover, multibody model, contact model, multiphysics model, unmanned vehicle, energy consumption, Mechanical engineering and machinery, and TJ1-1570

The employment of vehicles such as rovers equipped with automictic and robotic systems in agriculture is an emerging field. The development of suitable simulation models can aid in the design and testing of agricultural rovers before prototyping. Here, we propose a simulation test rig based on a multibody model to investigate the main issues connected with agricultural rover designs. The results of the simulations show significant differences between the two structures, especially regarding the energy savings, which is a key aspect for the applicability of a rover in field operations. The modular structure of the proposed simulation model can be easily adapted to other vehicle structures.

additive manufacturing, electrical machines, metal 3D-printing, electrical machine cooling, Mechanical engineering and machinery, and TJ1-1570

Additive manufacturing (AM) is a key technology for advancing many fields, including electrical machines. It offers unparalleled design freedom together with low material waste and fast prototyping, which is why it has become to focus of many researchers. For electrical machines, AM allows the production of designs with optimized mechanical, electromagnetic and thermal parameters. This paper attempts to give the reader an overview of the existing research and thermal solutions which have been realized with the use of AM. These include novel heat sink and heat exchanger designs, solutions for cooling the machine windings directly, and additively manufactured hollow windings. Some solutions such as heat pipes, which have been produced with AM but not used to cool electrical machines, are also discussed, as these are used in conventional designs and will certainly be used for additively manufactured electrical machines in the future.

Additive Manufacturing (AM), digital manufacturing, void analysis, X-ray Computed Tomography (XCT), mechanical properties, fiber orientation, 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 great potential of Extrusion Additive Manufacturing (EAM) for structural prototyping in the automotive industry is severely limited by the directional bias in the build direction. The layerwise fabrication leads to reduced mechanical properties at the layer-to-layer interface compared to the bulk of the strand. Especially for the often-used semi-crystalline thermoplastics, the mechanical properties strongly depend on the processing parameters, even more so if short fibers are used as fillers. Therefore, ideal processing windows in which the mechanical strength and modulus in the z-direction reach their maximum can be identified for these parameters, resulting in a reduced directional bias. The influence of the EAM processing parameters on mechanical strength has already been investigated, correlating strength with thermal conditions during printing. However, these considerations did not distinguish between the thermal effect on the polymer properties, the formation of voids and pores at the layer interface, and the resulting fiber orientation for different strand proportions. Therefore, in this study, the effect of different processing temperatures and layer heights on the pore size and distribution, as well as the fiber orientation in the different regions of the mesostructure was investigated using X-ray Computed Tomography (XCT).

prototyping, additive manufacturing, build orientation, accuracy, printing time, 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 optimal three-dimensional (3D) printing parameters of removable partial denture (RPD) frameworks should be studied to achieve the best accuracy, printing time, and least materials consumed. This study aimed to find the best build angle and support structures’ diameter of the 3D printed (RPD) framework. Sixty (RPD) frameworks (10 in each group) were manufactured by digital light processing (DLP) 3D printing technology at three build angles (110-D, 135-D, and 150-D) and two support structures diameters (thick, L, and thin, S). Six groups were named according to their printing setting as (110-DS, 135-DS, 150-DS, 110-DL, 135-DL, and 150-DL). Frameworks were 3D scanned and compared to the original cast surface using 3D metrology software (Geomagic Control X; 3D Systems, Rock Hill, SC). Both printing time and material consumption were also recorded. Data were tested for the significant difference by one-way analysis of variance (ANOVA) test at (α = 0.05). The correlations between outcome parameters were also calculated. The 110-DL group showed the least accuracy. Significantly, the printing time of the 150-D groups had the lowest time. Material consumption of group 110-DS presented the lowest significantly statistical value. Printing time had a linear correlation with both accuracy and material consumption. Within the study limitations, the 150-degree build angle and thin diameter support structures showed optimal accuracy and time-saving regardless of material consumption.

laser powder bed fusion, remelting strategy, surface quality, relative density, 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

Due to the high degree of design freedom and rapid prototyping, laser powder bed fusion (L-PBF) presents a great advantage in the super-hard cemented carbide compared with conventional methods. However, optimizing processing parameters to improve the relative density and surface roughness is still a challenge for cemented carbide fabricated by L-PBF. For this, the effect of the remelting strategy on the forming quality of the L-PBF processed cemented carbide was studied in this article, aiming to explore a suitable process window. The surface quality, relative density, microstructure, and microhardness of the cemented carbide parts fabricated under a single melting and remelting strategy were compared. The results showed that the remelting strategy could efficiently improve the specimens’ surface quality and relative density. Besides, the cracks were not obviously aggravated, and the WC grains could distribute more homogeneously on the binder matrix under the remelting strategy. Therefore, the microhardness showed an improvement compared to the single melting strategy.

education, electronics engineering, programmable platforms, rapid prototyping, reconfigurable electronics, sensors, Mechanical engineering and machinery, and TJ1-1570

This case report presents a real example of a study which introduces the use of reconfigurable platforms in the teaching of electronics engineering to establish a bridge between theory and practice. This gap is one of the major concerns of the electronics engineering students. Different strategies, such as simulation tools or breadboard implementations, have been followed so far to make it easier for students to practice what they study in lectures. However, many students still claim to have problems when they face real practical implementations. The use of reconfigurable platforms as a teaching tool is proposed to provide the students the possibility of fast experimentation, reducing both development time and the learning curve. In addition, reconfigurable platforms available on the market make this methodology suitable to be applied throughout the different courses of their curricula. The feasibility of this approach is demonstrated in a course at the M.Eng. level, where the objective is the study, design and development of electronic sensor nodes. We firmly consider, based on the students’ results and reflections collected during the course, that this methodology helps students to address the theoretical framework from a practical viewpoint, as well as to acquire some of the fundamental skills for their professional careers, such as the usage of communication protocols and embedded systems programming, in a more intuitive way when compared to traditional teaching methodologies.

microfluidics, PCB, rapid prototyping, 3D printing, PCB-MEMS, Mechanical engineering and machinery, and TJ1-1570

The combination of printed circuit boards (PCB) and microfluidics has many advantages. The combination of electrodes, sensors and electronics is needed for almost all microfluidic systems. Using PCBs as a substrate, this integration is intrinsic. Additive manufacturing has become a widely used technique in industry, research and by hobbyists. One very promising rapid prototype technique is vat polymerization with an LCD as mask, also known as masked stereolithography (mSLA). These printers are available with resolutions down to 35 µm, and they are affordable. In this paper, a technology is described which creates microfluidics on a PCB substrate using an mSLA printer. All steps of the production process can be carried out with commercially available printers and resins: this includes the structuring of the copper layer of the PCB and the buildup of the channel layer on top of the PCB. Copper trace dimensions down to 100 µm and channel dimensions of 800 µm are feasible. The described technology is a low-cost solution for combining PCBs and microfluidics.

microfluidic, centrifugal, embedded membrane, membrane deswelling, orthogonal flow, exponential decay, Mechanical engineering and machinery, and TJ1-1570

To bring to bear the power of centrifugal microfluidics on vertical flow immunoassays, control of flow orthogonally through nanoporous membranes is essential. The on-disc approach described here leverages the rapid print-cut-laminate (PCL) disc fabrication and prototyping method to create a permanent seal between disc materials and embedded nanoporous membranes. Rotational forces drive fluid flow, replacing capillary action, and complex pneumatic pumping systems. Adjacent microfluidic features form a flow path that directs fluid orthogonally (vertically) through these embedded membranes during assay execution. This method for membrane incorporation circumvents the need for solvents (e.g., acetone) to create the membrane-disc bond and sidesteps issues related to undesirable bypass flow. In other recently published work, we described an orthogonal flow (OF) platform that exploited embedded membranes for automation of enzyme-linked immunosorbent assays (ELISAs). Here, we more fully characterize flow patterns and cellulosic membrane behavior within the centrifugal orthogonal flow (cOF) format. Specifically, high-speed videography studies demonstrate that sample volume, membrane pore size, and ionic composition of the sample matrix significantly impact membrane behavior, and consequently fluid drainage profiles, especially when cellulosic membranes are used. Finally, prototype discs are used to demonstrate proof-of-principle for sandwich-type antigen capture and immunodetection within the cOF system.

development, multimedia, scientific approah., Education (General), L7-991, Science (General), and Q1-390

This research was a development research using the Plomp model with 3 phases, namely preliminary research consisting of: needs analysis, curriculum analysis, concept analysis and analysis of student characteristics. The development or prototyping phase consists of: self evaluation and expert review, one-to-one evaluation and small group evaluation. And the assessment phase consists of testing the effectiveness by testing the results of learning mathematics. The results of this study indicate that the average score of the material aspect by mathematicians is 85.84%; educational technology expert 81.82%; and linguists 93.75%. Therefore, multimedia obtained a total average score of 89.10% or very valid criteria. Based on the multimedia practicality test conducted by an educator and 6 students, it shows that multimedia gets an average score of 86.15% or very practical criteria with an average of 81.67% by the teacher's response and 90.63% by the student's response. Based on the multimedia effectiveness test by giving math problem solving test questions obtained 78.26% of students who meet completeness, this shows that multimedia mathematics meets the criteria of being very valid, very practical and very effective for improving mathematical problem solving for students of MTs Muhammadiyah Class VIII.

Badminton, Shuttlecock, Robot, Mechanical manufacturing, and Technology

Modern badminton training machines, which circumvents the requirement of two opposing players for conducting a match, are either expensive or has complex operation. This research involved the prototyping of a shuttlecock robot that enables a badminton player to practice independently. First, a three-dimensional model of the badminton robot was designed. Subsequently, the dynamics of the mechanism were evaluated. Next, the hardware was designed using MATLAB. Finally, the trajectory of the badminton shuttlecock was determined using a series of experimental tests. The as-developed product was reliable and stable, enabling badminton players to practice independently. Moreover, the designed robot can be manufactured at a lower cost than similar machines developed in other studies.

Autonomous robot, Assembly, Motion generation, Deep predictive learning, Technology, Mechanical engineering and machinery, TJ1-1570, Control engineering systems. Automatic machinery (General), TJ212-225, Machine design and drawing, TJ227-240, Technology (General), T1-995, Industrial engineering. Management engineering, T55.4-60.8, Automation, T59.5, Information technology, and T58.5-58.64

Abstract We propose a novel robotic system that combines both a reliable programming-based approach and a highly generalizable learning-based approach. How to design and implement a series of tasks in an atypical environment is a challenging issue. If all tasks are implemented using a programming-based approach, the development costs will be huge. However, if a learning-based approach is used, reliability is an issue. In this paper, we propose novel design guidelines that focus on the respective advantages of programming-based and learning-based approaches and select them so that they complement each other. We use a program-based approach for motions that is rough behavior and a learning-based approach for motion that is required complex interaction between robot and object of robot tasks and are difficult to achieve with a program. Our learning approach can easily and rapidly accomplish a series of tasks consisting of various motions because it does not require a computational model of an object to be designed in advance. We demonstrate a series of tasks in which randomly arranged parts are assembled using an actual robot.

Medicine and Science

Abstract The intra-image identification of DNA structures is essential to rapid prototyping and quality control of self-assembled DNA origami scaffold systems. We postulate that the YOLO modern object detection platform commonly used for facial recognition can be applied to rapidly scour atomic force microscope (AFM) images for identifying correctly formed DNA nanostructures with high fidelity. To make this approach widely available, we use open-source software and provide a straightforward procedure for designing a tailored, intelligent identification platform which can easily be repurposed to fit arbitrary structural geometries beyond AFM images of DNA structures. Here, we describe methods to acquire and generate the necessary components to create this robust system. Beginning with DNA structure design, we detail AFM imaging, data point annotation, data augmentation, model training, and inference. To demonstrate the adaptability of this system, we assembled two distinct DNA origami architectures (triangles and breadboards) for detection in raw AFM images. Using the images acquired of each structure, we trained two separate single class object identification models unique to each architecture. By applying these models in sequence, we correctly identified 3470 structures from a total population of 3617 using images that sometimes included a third DNA origami structure as well as other impurities. Analysis was completed in under 20 s with results yielding an F1 score of 0.96 using our approach.

controller hardware-in-the-loop, digital controller, FPGA, power electronics education, rapid control prototyping, real-time simulation, Environmental effects of industries and plants, TD194-195, Renewable energy sources, TJ807-830, Environmental sciences, and GE1-350

Power electronics is a core subject in electrical and electronics engineering at the undergraduate level. The rapid growth in the field of power electronics requires necessary changes in the curricula and practica for power electronics. The proposed next-generation power electronics teaching laboratory changes the learning paradigm for this subject and is for the first time used for teaching purposes in Pakistan. The proposed controller hardware-in-the-loop (CHIL) laboratory enabled students to design, control, and test power converters without the fear of component failure. CHIL setup allowed students to directly validate the physical controller without the need for any real power converter. This allowed students to obtain more repeatable results and perform extreme digital controller testing of power converters that are otherwise not possible on real hardware. Furthermore, students could start learning power electronics concepts with hardware from the beginning on a safe, versatile, fully interactive, and reconfigurable platform. The proposed laboratory meets the accreditation board for engineering and technology (ABET) student outcome criterion K such that students can continue with the same hardware and software toolset for graduate and research purposes. The knowledge and skills acquired during undergraduate years can help students create new solutions for power electronics systems and develop their expertise in the field of power electronics. The results obtained from the survey indicated that the majority of the students were satisfied with the laboratory setup. They also expressed appreciation over the provision of a high-level graphical language “LabVIEW” for the digital controllers compared to conventional low-level text-based languages such as VHDL, Verilog, C, or C++.

gestures, interaction, natural user interface, gestural input, freehand, hands-free, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, and QD1-999

Natural user interfaces based on hand gestures are becoming increasingly popular. The need for expensive hardware left a wide range of interaction possibilities that hand tracking enables largely unexplored. Recently, hand tracking has been built into inexpensive and widely available hardware, allowing more and more people access to this technology. This work provides researchers and users with a simple yet effective way to implement various one-handed gestures to enable deeper exploration of gesture-based interactions and interfaces. To this end, this work provides a framework for design, prototyping, testing, and implementation of one-handed gestures. The proposed framework was implemented with two main goals: First, it should be able to recognize any one-handed gesture. Secondly, the design and implementation of gestures should be as simple as performing the gesture and pressing a button to record it. The contribution of this paper is a simple yet unique way to record and recognize static and dynamic one-handed gestures. A static gesture can be captured with a template matching approach, while dynamic gestures use previously captured spatial information. The presented approach was evaluated in a user study with 33 participants and the implementable gestures received high accuracy and user acceptance.

vibration isolator, quasi-zero stiffness, pneumatic cylinder, complex dynamic, sliding friction, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, and QD1-999

This paper focuses on analyzing the dynamic response of an innovated quasi-zero stiffness pneumatic vibration isolator (QZSPVI) using two mechanisms, including wedge and semicircle cam. Different from other studies relating quasi-zero stiffness isolation system, the pneumatic cylinder in this paper works as an air spring in order to easily adjust the dynamic stiffness of the proposed system according to the change of the isolated load through regulating the pressure. Firstly, the dynamic stiffness of the QZSPVI will be analyzed. Then, the condition for which the minimum dynamic stiffness is quasi-zero around the equilibrium position is also determined. The fundamental resonance response of the QZSPVI subjected to the externally harmonic force is analyzed through multi-scale method and the numerical simulations are verified. Secondly, due to exiting relative sliding frictional phenomenon between the cylinder and piston, instead of an experiment, another key content of this work is to identify the friction force model of the cylinder through virtual prototyping model. From this identified result, the complex dynamic response of the QZSPVI and coexistence of multiple solutions will be discovered by realizing the direct integration of the original dynamic equation through using the 5th-order Runge–Kutta algorithm. The analysis and simulation results clearly show the advantages of the proposed model against the equivalent pneumatic vibration isolator (EPVI), which only employs the wedge mechanism. This research will offer a useful insight into design and QZSPVI in practice.

3D-cell biology, teflon, hanging-drop culture, delta-kinematic, rapid-prototyping, histology, Technology, Biology (General), and QH301-705.5

The wide use of 3D-organotypic cell models is imperative for advancing our understanding of basic cell biological mechanisms. For this purpose, easy-to-use enabling technology is required, which should optimally link standardized assessment methods to those used for the formation, cultivation, and evaluation of cell aggregates or primordial tissue. We thus conceived, manufactured, and tested devices which provide the means for cell aggregation and online monitoring within a hanging drop. We then established a workflow for spheroid manipulation and immune phenotyping. This described workflow conserves media and reagent, facilitates the uninterrupted tracking of spheroid formation under various conditions, and enables 3D-marker analysis by means of 3D epifluorescence deconvolution microscopy. We provide a full description of the low-cost manufacturing process for the fluidic devices and microscopic assessment tools, and the detailed blueprints and building instructions are disclosed. Conclusively, the presented compilation of methods and techniques promotes a quick and barrier-free entry into 3D cell biology.

Autotransplantation, Rapid prototyping, Root canal treatment, Dentistry, and RK1-715

Abstract Background Autotransplantation is a beneficial treatment with a high success rate for young patients. However, most adult patients require root canal treatment (RCT) of the donor teeth after the autotransplantation procedure, which causes a prolonged treatment time and additional expenses and increases the rate of future tooth fracture. Rapid prototyping (RP)-assisted autotransplantation shortens the extra-alveolar time and enables a superior clinical outcome. However, no cohort studies of the application of this method on adult populations have been reported. Methods This study is a retrospective cohort study. All patients underwent autotransplantation from 2012 to 2020 in the Kaohsiung and Chia-Yi branches of Chang Gung Memorial Hospital, and the procedure and clinical outcomes were analysed. Differences in clinical outcomes, age, sex, extra-alveolar time, fixation method, and RCT rate were compared between the two groups. Results We enrolled 21 patients, 13 treated using the conventional method and 8 treated using the RP-based technique. The RCT rates of the conventional group and RP group were 92.3% and 59%, respectively. The mean age of the two groups was significantly different (28.8 ± 10 vs. 21.6 ± 2.1); after performing subgroup analysis by excluding all of the patients aged > 40 years, we found that the RCT rates were still significantly different (91.0% vs. 50%). The mean extra-alveolar time was 43 s in the RP group, and the autotransplantation survival rate in both groups was 100%. Conclusions Rapid prototyping-assisted autotransplantation was successfully adopted for all patients in our study population. By shortening the extra-alveolar time, only 50% of the patients required a root canal treatment with a 100% autotransplantation survival rate. Trial Registration : Retrospectively registered.

Research data management, Prototyping, Catalysis research data, FAIR data principles, Chemistry, and QD1-999

The UK Catalysis Hub (UKCH) is designing and implementing an infrastructure to facilitate the management of research data produced by researchers, the Catalysis Data Infrastructure (CDI). The CDI is proposed to encompass the presentation of research outputs (publications and data) in a digital repository that brings together an array of heterogeneous data types. The CDI is designed to hold references to research outputs, maintains links between them and promotes publishing and sharing of data. The proposal is to create persistent relationships between the different types of data and publications complying with FAIR data principles (findability, accessibility, interoperability, and reuse). In this paper, we will discuss how the elicited requirements for data management are being incorporated in the design of the CDI. The prototype has been used in discussion with researchers and in presentations to the UKCH community, generating increased interest and providing ideas for further development. Additionally, the CDI prototype and its code are publicly available for further analysis.

3D printing technologies, biosensors, electrochemical biosensors, material extrusion, vat photopolymerization, material jetting, Biochemistry, and QD415-436

Recent advances in 3D printing technologies and materials have enabled rapid development of innovative sensors for applications in different aspects of human life. Various 3D printing technologies have been adopted to fabricate biosensors or some of their components thanks to the advantages of these methodologies over the traditional ones, such as end-user customization and rapid prototyping. In this review, the works published in the last two years on 3D-printed biosensors are considered and grouped on the basis of the 3D printing technologies applied in different fields of application, highlighting the main analytical parameters. In the first part, 3D methods are discussed, after which the principal achievements and promising aspects obtained with the 3D-printed sensors are reported. An overview of the recent developments on this current topic is provided, as established by the considered works in this multidisciplinary field. Finally, future challenges on the improvement and innovation of the 3D printing technologies utilized for biosensors production are discussed.

web-based, examination, randomization, auto-grading, e-learning, mysql, client/server, resumption, scheduling, recovery, Technology (General), T1-995, Industry, and HD2321-4730.9

This paper presents the development of a web-based examination system that focuses on automated resolution of faults such as power, network, or component failure that may occur when an e-learning system is used to conduct an examination. This system can withstand various challenges that hinder the adoption of e-learning technologies in developing countries. This is important because it will reduce the time and cost involved in conducting large scale examinations by tertiary institutions without the need to upgrade existing infrastructures. These institutions will not necessarily require uninterrupted power or network connection to conduct web-based examinations as the system can easily resume if such an incident occurs. The architecture of the proposed web-based online examination system provides for integrated management of functions such as question pool creation and update, examination monitoring, failure toleration and recovery, automated grading, and randomization. The system also eliminates the need for manual scheduling of examinations which requires much planning and is error-prone. Different examinations can be scheduled to run simultaneously. The design technology adopted for the implementation is a client/server technology. The incremental software development model in conjunction with prototyping technique was adopted in the development of the web-based examination system due to the iterative nature of the developed software. The system was developed using PHP, JavaScript, Ajax and MySQL. The system has been applied to conduct an examination involving more than 20,000 students per semester at University of Calabar. It has been proved to save efforts of teachers and students.

mass mixing, geotechnics, cement transporter, computer simulations, finite element method, and Technology

Regarding the vehicles used in civil engineering, some are manufactured in large quantities and some (especially innovative ones) are still prototypes manufactured for tests or rare use. The latter describes the case of equipment for mass mixing (mass stabilization) technology which is not widely used compared to other types of geotechnical equipment. The purpose of this paper is to present a research and development project on an innovative cement transporter designed for mass mixing. Three-dimensional models and advanced finite element method (FEM) calculations are used to validate the design of the most important part of the cement transporter—the frame connecting the undercarriage and the upper carriage. The results presented in the paper confirm that the design based on the strength criterion and boundary conditions from geotechnical safety requirements can be used for designing the parts of the prototype vehicle. It is concluded that in innovative vehicle design for geotechnical purposes, the analyses may extend beyond the standard static analyses.

building automation, occupant feedback, building information modeling, building management, prototyping, and Technology

Building automation is concerned with closed- and open-loop control of building services such as heating, cooling, ventilation and air conditioning, lighting and shading. The ultimate goal is to reduce energy consumption while providing comfort for the occupants. However, ensuring human comfort is a complex affair. In case of dissatisfaction, users need to inform the building operators about apparently badly adjusted setpoints. Then, service units of the facility management have to manually analyze how to improve the situation. Due to the complex characteristics of human perception and derived feedback, this can become a troublesome and time-consuming task. This paper describes the main results of our investigations to improve occupant comfort in office buildings using environmental information monitored by a Wireless Sensor Network (WSN) and human perception collected from a feedback tool. A joint information base aligned with static data from building information modeling integrates the information gathered. Reasoning on these data sources allows adjustments of the Building Automation System (BAS) to automatically enhance the tenant’s comfort or suggest necessary adjustments for facility managers. Communication between the different system components is handled via Message Queuing Telemetry Transport (MQTT). A real-world field study shows the potential of the developed approach, proves its feasibility, and demonstrates the functionality of the feedback tool.