Functional Prototype Research Articles

Towards Cooperative Perception Services for ITS: Digital Twin in the Automotive Edge Cloud

We demonstrate a working functional prototype of a cooperative perception system that maintains a real-time digital twin of the traffic environment, providing a more accurate and more reliable model than any of the participant subsystems—in this case, smart vehicles and infrastructure stations—would manage individually. The importance of such technology is that it can facilitate a spectrum of new derivative services, including cloud-assisted and cloud-controlled ADAS functions, dynamic map generation with analytics for traffic control and road infrastructure monitoring, a digital framework for operating vehicle testing grounds, logistics facilities, etc. In this paper, we constrain our discussion on the viability of the core concept and implement a system that provides a single service: the live visualization of our digital twin in a 3D simulation, which instantly and reliably matches the state of the real-world environment and showcases the advantages of real-time fusion of sensory data from various traffic participants. We envision this prototype system as part of a larger network of local information processing and integration nodes, i.e., the logically centralized digital twin is maintained in a physically distributed edge cloud.

IndoorCare: Low-Cost Elderly Activity Monitoring System through Image Processing.

The Portuguese population is aging at an increasing rate, which introduces new problems, particularly in rural areas, where the population is small and widely spread throughout the territory. These people, mostly elderly, have low income and are often isolated and socially excluded. This work researches and proposes an affordable Ambient Assisted Living (AAL)-based solution to monitor the activities of elderly individuals, inside their homes, in a pervasive and non-intrusive way, while preserving their privacy. The solution uses a set of low-cost IoT sensor devices, computer vision algorithms and reasoning rules, to acquire data and recognize the activities performed by a subject inside a home. A conceptual architecture and a functional prototype were developed, the prototype being successfully tested in an environment similar to a real case scenario. The system and the underlying concept can be used as a building block for remote and distributed elderly care services, in which the elderly live autonomously in their homes, but have the attention of a caregiver when needed.

Tensile properties of polyamide 12 / black with 10wt.% copper samples manufactured by laser powder bed fusion

In laser powder bed fusion (L-PBF) of polymers, a proven material for biomedical applications is Polyamide 12 (PA 12) that is used for production of functional prototypes and end-use parts. The aim of this study is to investigate properties of in situ copper-modified polyamide (Sintratec PA12/B) at 10 wt.% Cu by L-PBF. Polymer-metal composites test samples were evaluated for their porosity, Cu distribution and tensile properties.

An Automatically Verified Prototype of the Tokeneer ID Station Specification

The Tokeneer project was an initiative set forth by the National Security Agency (NSA, USA) to be used as a demonstration that developing highly secure systems can be made by applying rigorous methods in a cost-effective manner. Altran UK was selected by NSA to carry out the development of the Tokeneer ID Station. The company wrote a Z specification later implemented in the SPARK Ada programming language, which was verified using the SPARK Examiner toolset. In this paper, we show that the Z specification can be readily and naturally encoded in the $$\{log\}$$ { l o g } set constraint language, thereby generating a functional prototype. Furthermore, we show that $$\{log\}$$ { l o g } ’s automated proving capabilities can discharge all the proof obligations concerning state invariants as well as important security properties. As a consequence, the prototype can be regarded as correct with respect to the verified properties. This provides empirical evidence that Z users can use $$\{log\}$$ { l o g } to generate correct prototypes from their Z specifications. In turn, these prototypes enable or simplify some verification activities discussed in the paper.

On shear fracture and morphological features of fused filament fabrication based almond skin reinforced PLA structures

ABSTRACT The polylactic acid (PLA) composite-based 3D printed functional prototypes have been widely explored for preparation of biomedical scaffolds with fused filament fabrication (FFF). But hitherto little has been reported on the use of the almond skin (AS) as reinforcement in PLA matrix for scaffolding applications with improved shear modulus (SM). In this study composite of PLA and AS was subjected to pull-out test to ensure SM and modulus of toughness (MOT), surface hardness and morphological investigations for use as scaffold. The results of study show that during pull-out test, maximum shear strength at peak (PSS) as 22.85MPa; maximum shear strength at break (BSS) as 20.56MPa was observed for samples printed with infill density (ID) 100%, infill angle (IA) 45° and infill speed (IS) 90 mm/s (on open source FFF setup). The maximum MOT as 25.50 MPa was noticed for sample printed at ID 60%, IA 45° and IS 50 mm/s. Further maximum SM as 21.80 MPa was observed for samples printed at ID 60%, IA 60° and IS 70 mm/s. The results have been supported by photo-micrographic analysis; surface hardness analysis; Taguchi and response surface methodology based historical data approach for optimisation of pull-out properties.

On flexural and pull out properties of smart polymer based 3D printed functional prototypes

On flexural and pull out properties of smart polymer based 3D printed functional prototypes

On flexural, wear and morphological properties of 3D printed almond skin powder reinforced PLA matrix

ABSTRACT In past one decade, some studies have been reported on use of natural fibre-reinforced thermoplastic matrix such as polylactic acid (PLA)-based 3D-printed functional prototypes for biomedical applications. But hitherto little has been reported on the flexural, wear and morphological properties of almond skin powder–-reinforced PLA matrixbased 3D-printed functional prototypes prepared by fused filament fabrication (FFF) as biomedical scaffold/implant. In this study, the 3D-printed functional parts were subjected to flexural, wear and morphological investigations. The results suggested that maximum flexural strength at break and peak was observed as 57.38 MPa and 63.761 MPa, respectively (while printing with FFF at infill density 60%, infill angle 60° and infill speed 70 mm/s). The results are supported with the optical photomicrographs and surface topography analysis, which shows that there is relation between mechanical and surface properties of functional prototypes. The minimum surface roughness (Ra) 19.98 nm has been observed for 3D-printed flexural samples at proposed settings.

On investigations of 3D printed nylon 6 parts prepared by fused filament fabrication

The fused filament fabrication (FFF) which is also known as freeform filament fabrication is one of the additive manufacturing techniques used for the fabrication of functional and nonfunctional prototypes. The previous studies have suggested that FFF process parameters have significant impact over the mechanical, thermal, surface, morphological and tribilogical properties of the 3D printed parts. The present study deals with the investigation for process parameters of FFF. In this study, three different process parameters namely; infill percentage, bed temperature and outer perimeter have been varied for the FFF process. The 3D printed nylon 6 prototypes (As per ASTM 638 type IV) were tested by universal tensile tester for investigation of ultimate tensile strength. The results of the study have suggested that at 100% infill percentage, 60% and 6 outer perimeters the ultimate tensile strength can be maximized.

Towards optimal toe-clearance in synthesizing polycentric prosthetic knee mechanism

Stability at the stance phase and near normal able-bodied swing phase kinematics are essential in designing the prosthetic knee mechanism for transfemoral amputees. Primarily, insufficient mid swing toe clearance results in asymmetrical gait patterns, leading to muscular-skeletal pain and joint degeneration. The present work is focused on synthesizing a polycentric knee mechanism to enhance the toe-clearance at mid-swing for safe level ground walking of amputees in developing countries. Both fixed and moving centrodes of the four-bar knee mechanism are considered in optimal synthesis of the mechanism for achieving able-bodied gait patterns using evolutionary algorithms in mechanism design software tools. The knee stability at heel contact, stabilizing moment at push-off, stable knee flexion range, maximum knee flexion and maximum toe-clearance at mid-swing are the parameters used for comparing the knee design with the existing commercially available designs. The optimized results are then verified experimentally by building a functional prototype using a 3 D printing technique. The designed mechanism executes nominal performance in four parameters and offers enhanced toe-clearance during mid-swing. This is a significant improvement over the existing designs for amputees to navigate comfortably on irregular terrain in developing countries.

The effect of a functional prototype on user acceptance in transportation: Assessing the level of acceptance before and after the first demonstration flight of an air taxi

Prototypes support the development of new technology by enabling to collect user feedback before full market readiness is achieved. However, this potential is often not fully exploited as physical prototypes are mainly used at more mature levels of technology development, after demonstrating full functionality. Using physical prototypes that are not fully functional at an early stage of technology maturity could lead to lower resource consumption as customer feedback could be incorporated faster and acceptance could be established. However, previous research has indicated differences in consumer attitudes toward technologies before and after users have experienced prototypes first-hand. Therefore, this paper investigates whether experiencing a functional physical prototype at an early stage of technology maturity affects consumer perception. For this purpose, we utilized the first flight of an air taxi in Europe since we were certain that the technology had not been seen in action or used before. We conducted two studies: Study 1, with 126 potential users in a within-subject design, and Study 2, with 539 potential users in a between-subject design. We did not detect significant effects on the participants’ attitudes before and after watching an air taxi flight in person in either study. Overall, the data suggests that a live demonstration of a technology is not necessary to gain a comprehensive picture of peoples’ attitudes toward it, which creates the possibility of examining the effects of more inexpensive technologies, such as virtual and augmented reality simulators in mobility research.

Map Whiteboard Cloud Solution for Collaborative Editing of Geographic Information

For the purpose of exploiting the potential of cloud connectivity in geographical information systems, the Map Whiteboard technology introduced in this article does for web mapping what Google Docs does for word processing; create a shared user interface where multiple parties collaboratively can develop maps and map data while seeing each other work in realtime. To develop the Map Whiteboard concept, we have applied a methodology whereby we have collected technical and functional requirements through a series of hackathons, implemented a prototype in several stages, and subjected this to rigorous testing in a lab environment and with selected users from relevant environments at intermediate scale. The work has resulted in a fully functional prototype that exploits WebSockets via a cloud service to reflect map and data changes between multiple connected clients. The technology has a demonstrated potential for use in a wide range of web GIS applications, something that is facilitated by the interfaces already implemented towards mainstream mapping frameworks like OpenLayers and QGIS-two of the most popular frameworks for Web GIS solutions. Further development and testing are required before operationalization in mission-critical environments. In conclusion, the Map Whiteboard concept offers a starting point for exploiting cloud connectivity within GIS to facilitate the digitalization of common processes within the government and private sector. The technology is ready for early adopters and welcomes the contribution of interested parties.

Optimizing e-Consultations to Adolescent Medicine Specialists: Qualitative Synthesis of Feedback From User-Centered Design

Backgrounde-Consultations between primary care physicians and specialists are a valuable means of improving access to specialty care. Adolescents and young adults (AYAs) face unique challenges in accessing limited adolescent medicine specialty care resources, which contributes to delayed or forgone care. e-Consultations between general pediatricians and adolescent medicine specialists may alleviate these barriers to care. However, the optimal application of this model in adolescent medicine requires careful attention to the nuances of AYA care.ObjectiveThis study aims to qualitatively analyze feedback obtained during the iterative development of an e-consultation system for communication between general pediatricians and adolescent medicine specialists tailored to the specific health care needs of AYAs.MethodsWe conducted an iterative user-centered design and evaluation process in two phases. In the first phase, we created a static e-consultation prototype and storyboards and evaluated them with target users (general pediatricians and adolescent medicine specialists). In the second phase, we incorporated feedback to develop a functional prototype within the electronic health record and again evaluated this with general pediatricians and adolescent medicine specialists. In each phase, general pediatricians and adolescent medicine specialists provided think-aloud feedback during the use of the prototypes and semistructured exit interviews, which was qualitatively analyzed to identify perspectives related to the usefulness and usability of the e-consultation system.ResultsBoth general pediatricians (n=12) and adolescent medicine specialists (n=12) perceived the usefulness of e-consultations for AYA patients, with more varied perceptions of potential usefulness for generalist and adolescent medicine clinicians. General pediatricians and adolescent medicine specialists discussed ways to maximize the usability of e-consultations for AYAs, primarily by improving efficiency (eg, reducing documentation, emphasizing critical information, using autopopulated data fields, and balancing specificity and efficiency through text prompts) and reducing the potential for errors (eg, prompting a review of autopopulated data fields, requiring physician contact information, and prompting explicit discussion of patient communication and confidentiality expectations). Through iterative design, patient history documentation was streamlined, whereas documentation of communication and confidentiality expectations were enhanced.ConclusionsThrough an iterative user-centered design process, we identified user perspectives to guide the refinement of an e-consultation system based on general pediatrician and adolescent medicine specialist feedback on usefulness and usability related to the care of AYAs. Qualitative analysis of this feedback revealed both opportunities and risks related to confidentiality, communication, and the use of tailored documentation prompts that should be considered in the development and use of e-consultations with AYAs.

Library free bulk detection of explosives – Combining simple sensors for resolving a complicated issue

Based on previous work a robust, mobile and fully functional prototype of a detector for energetic materials was developed. The prototype works in a library free manner – it detects explosives regardless of the analyte’s chemical nature. Based on 170 experiments a detection rate of 99,4 % was reached. The detection algorithm was based on 13 explosive and 4 benign materials. The explosives were chosen to cover most common chemical classes and the benign materials included the ones which could easily be mistaken for explosives either optically or by their chemical constitution. In additional experiments, the possibility of library free and automatized operation was proven. Those experiments were performed in a double-blind mode and resulted in 9 of 10 right assignments (8 energetic materials and one benign) and 1 false positive. Sophisticated modular electronics allows quick exchange of sensors in case of malfunction or for experimental reasons. The application of custom metal oxide semiconductor gas sensors has not only the potential for significant power saving and therefore for making the prototypical detection-device suitable for mobile, battery powered application but additionally shortens the detection procedure runtime remarkably while still maintaining a close to 100 % detection rate, thus bringing the detector prototype one step closer to the market. Additional information about the chemical class of the analyzed substance can also be acquired, which can be a crucial advantage for first responders.

A Secure Link-Layer Connectivity Platform for Multi-Site NFV Services

Network Functions Virtualization (NFV) is a key technology for network automation and has been instrumental to materialize the disruptive view of 5G and beyond mobile networks. In particular, 5G embraces NFV to support the automated and agile provision of telecommunication and vertical services as a composition of versatile virtualized components, referred to as Virtual Network Functions (VNFs). It provides a high degree of flexibility in placing these components on distributed NFV infrastructures (e.g., at the network edge, close to end users). Still, this flexibility creates new challenges in terms of VNF connectivity. To address these challenges, we introduce a novel secure link-layer connectivity platform, L2S. Our solution can automatically be deployed and configured as a regular multi-site NFV service, providing the abstraction of a layer-2 switch that offers link-layer connectivity to VNFs deployed on remote NFV sites. Inter-site communications are effectively protected using existing security solutions and protocols, such as IP security (IPsec). We have developed a functional prototype of L2S using open-source software technologies. Our evaluation results indicate that this prototype can perform IP tunneling and cryptographic operations at Gb/s data rates. Finally, we have validated L2S using a multi-site NFV ecosystem at the Telefonica Open Network Innovation Centre (5TONIC), using our solution to support a multicast-based IP television service.

Development of Fused Filament Fabrication desktop 3D printer enclosure using axiomatic design principles

Additive manufacturing through Fused Filament Fabrication is one of the most spread methods for obtaining functional prototypes and components, mainly for single parts demands or small manufacturing lots. This direction of use presumes the use of engineering polymers in the manufacturing process, materials that require precise control of the environment regarding printing temperature and moisture. A Do-It-Yourself enclosure mock-up for engineering polymers processing was obtained using the Axiomatic Design principles. The enclosure is compatible with low-cost Fused Filament Fabrication desktop 3D printers and satisfies the functional requirements regarding manufacturing and secure usage of engineering-grade polymers. In addition, the presented design solved the requirements regarding surveillance and remote control during the manufacturing process.

Building a continuous passive mobilization machine (CPM) for the inferior limb recuperation

This paper is presenting the projection and realization of a passive mobilization device (CPM), used for rehabilitate lower knee articulation conditions, such as post-traumatic conditions, degenerative, ligamento-plastic chirurgical interventions, meniscectomy and in special patients who have had been under knee prosthesis chirurgical interventions, this one being the one which causes the biggest issues in the rehabilitation process. Also, in this paper are figured the main steps which are followed throughout the building process of a Low-Cost functional prototype and its way of function.

On 3D printing of PA6-10% almond skin powder reinforced composite

In past one decade, polyamide (PA)6 feedstock filaments has proved its capabilities for fused deposition modeling (FDM) based functional prototypes requiring wear and impact resistance. The almond skin powder (ASP) is organic kitchen waste material, which has highest strength to weight ratio. Some researchers have developed PA6 based composite feedstock filament reinforced with ASP. But hitherto little has been reported on use of ASP reinforced PA6 based composite filament for 3D printing (using FDM) and its printing capabilities. In this research work an effort has been made to 3D print, 10% (by weight) ASP reinforced PA6 composite filament with open source FDM setup as a pilot study. The results are supported with mechanical testing, optical photo-micro graphical analysis. The functional prototype can be very useful in meta-material printing (requiring high modulus of toughness) and rapid tooling applications.

A Service-Oriented Approach for Sensing in the Internet of Things: Intelligent Transportation Systems and Privacy Use Cases

This paper presents a Sensing-as-a-Service run-time Service Oriented Architecture (SOA), called 3SOA, for the development of Internet of Things (IoT) applications. 3SOA aims to allow interoperability among various IoT platforms and support service-oriented modelling at high levels of abstraction where fundamental SOA theories and techniques are fully integrated into a practical software engineering approach. 3SOA abstracts the dependencies of the middleware programming model from the application logic. This abstraction allows the development efforts to focus on writing the application logic independently from hardware platforms, middleware, and languages in which applications are programmed. To achieve this result, IoT objects are treated as independent entities that may interact with each other using a well-defined message exchange sequence. Each object is defined by the services it provides and the coordination protocol it supports. Objects are then able to coordinate their resources to address the global objectives of the system. To practically validate our proposals, we demonstrate an intelligent transportation system and data privacy functional prototypes as proof of concepts. The use cases show that 3SOA and the presented abstraction language allow the amalgamation of macroprogramming and node-centric programming to develop real-time and efficient applications over IoT.

Challenge-based and Competency-based Assessments in an Undergraduate Programming Course

In this work, we investigate an optimal assessment strategy to measure student learning in the first-year undergraduate engineering course at X-Department at X University. Specifically, we evaluate and compare challenge-based and competency-based assessment strategies. In the challenge-based approach, the students are required to design a C++-based application that meet the required design objectives. The competency-based assessment involves assessing learning by asking a variety of pointed questions pertaining to a single or a small group of concepts. After studying the performance of 207 students, we found that in the challenge-based assessment, due to the complex nature of the questions that assess numerous concepts simultaneously, students who are not very thorough with even one or two concepts fared very poorly since they were unable to finish the challenge and present a functional prototype of the program. On the other hand, the competency-based assessment allowed for a more balanced approach in which the students’ learning was reflected more accurately by their performance in the various assessments.

Ciudad Antigua: from remote sensing to virtual interactive experience of a pre-Hispanic settlement in Colombia

This study addresses the first photogrammetry reconstruction of Ciudad Antigua (CA), a pre-Hispanic archaeological site in Sierra Nevada de Santa Marta (SNSM), which is located in northern Colombia. The construction characteristics and symbolic relevance of places such as Ciudad Antigua, constitute a major part of the cultural heritage of Colombia. However, the remote location and limited public knowledge of the place have proven to be a disadvantage for the protection and conservation of this site. With this virtual representation project, we seek to fulfill three objectives: (1) Establish a strategy to preserve at-risk, remote archaeological sites through digital artifacts; (2) Use computational processes to go beyond representation and further analyze spatial components of the site; and (3) Spark and strengthen community interest in the history, architecture, design, and archaeology of SNSM. This study applies visualization and computation techniques to remote vestiges of cultural value, and demonstrates how these techniques can contribute to the social appropriation and protection of these ancient settlements. We created a functional prototype that could make the results of this research more readily available to the general public.