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ENGINEERING, MULTIDISCIPLINARY, UCD, UXD, SCRUM, Human Factors, Usability, Prototyping, HCD, Agile UX, Lean UX, Factores Humanos, Usabilidad, and Prototipado

This paper presents a methodological proposal that is based on powerful current approaches to the software development process: agile methodologies (SCRUM, Lean UX), user-centered design (UCD) and user experience design (UXD). Specifically, we have adapted some of the characteristics of the agile methodologies, which have allowed us to produce useful prototypes that are focused on the users while receiving constant feedback from them. The main goal of the proposed methodology is to identify usability problems and UX factors in the early stages of educational software development. Furthermore, we have also applied and validated the proposal during the framework development of an educational software project for users with special educational needs. A specific case taking into account key usability issues to support students with special education needs (SEN) is presented. In conclusion, we state that the proposed methodology could be a good design process philosophy to follow in the development of software projects in general, and in educational projects in particular.
Este artículo presenta una propuesta metodológica basada en los enfoques actuales del proceso de desarrollo de software: las metodologías ágiles (SCRUM), centradas en el usuario (UCD) y el diseño de experiencia de usuario (UXDy Lean UX). Así, hemos adaptado algunas de las características de las metodologías ágiles que nos han permitido producir prototipos centrados en los usuarios con retroalimentación constante de ellos. El objetivo principal de esta propuesta es identificar problemas de usabilidad y factores UX en las primeras etapas de desarrollo de software educativo. Además, hemos aplicado y validado esta propuesta en el marco de un proyecto de software educativo para los usuarios con necesidades educativas especiales. La metodología propuesta puede ser una buena filosofía de diseño a seguir en los proyectos de desarrollo de software en general, y en proyectos educativos en particular.

Geology, Géologie, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Informatique; automatique theorique; systemes, Computer science; control theory; systems, Intelligence artificielle, Artificial intelligence, Reconnaissance des formes. Traitement numérique des images. Géométrie algorithmique, Pattern recognition. Digital image processing. Computational geometry, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Généralités, General, Métrologie industrielle. Contrôle, Industrial metrology. Testing, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Radiotherapie. Traitement instrumental. Physiotherapie. Reeducation. Readaptation, orthophonie, crenotherapie. Traitement dietetique et traitements divers (generalites), Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects), Orl et stomatologie, Ent and stomatology, Maladies des voies aérodigestives supérieures, Diseases of the upper aerodigestive tract, Commande numérique calculateur, Computer digital control, Control numérico computador, Dentisterie, Dentistry, Odontología, Fabrication assistée, Computer aided manufacturing, Fabricación asistida por computador, Facteur réflexion, Reflectance, Coeficiente reflexión, Forme géométrique, Geometrical shape, Forma geométrica, Image tridimensionnelle, Tridimensional image, Imagen tridimensional, Interférométrie optique, Optical interferometry, Interferometría óptica, Langage CAML, CAML language, Laser, Láser, Méthode projection, Projection method, Método proyección, Métrologie surface, Surface metrology, Metrología superficie, Paramètre ordre, Order parameter, Parámetro orden, Pilotage ordinateur, Computer control, Control por ordenador, Prototypage rapide, Rapid prototyping, Prototipificación rápida, Reconstruction image, Image reconstruction, Reconstrucción imagen, Scanneur, Scanner, Escáner, Sondage laser, Laser sounding, Sondeo láser, Temps traitement, Processing time, Tiempo proceso, Traitement image, Image processing, Procesamiento imagen, Vision ordinateur, Computer vision, Visión ordenador, 3D reconstruction, fringe projection, and laser scanner

The rapid prototyping and copying of real 3D objects play a key role in some industries. Both applications rely on the generation of appropriated computer aided manufacturing (CAM) files. These files represent a set of coordinates of an object and can be understood by a computer numerically controlled (CNC) machine. Non-contact techniques, like laser scanning and fringe projection, are among the possibilities for obtaining such CAM files. In this work, a comparison between the two aforementioned non-contact techniques is presented. The comparison is made based on their performance as candidates for generating CAM files of objects of high reflectivity and maximum lateral dimensions of the order of 15 mm The parameters tested are the quality of the 3D reconstruction, the processing time, and the possibility of these being implemented in industrial scenarios, among others. Under the scope of these parameters, it is concluded that laser scanning offers superior performance for the kind of objects here considered. The techniques are evaluated with dental pieces in order to validate these methodologies in the rapid prototyping and copying of teeth.

Science technology, industry, Sciences et technologies, industries, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Métrologie industrielle. Contrôle, Industrial metrology. Testing, Généralités, General, Moteurs et turbines, Engines and turbines, Moteurs à combustion interne: moteurs à essence, diesels, etc, Internal combustion engines: gazoline engine, diesel engines, etc, Conception machine, Machine design, Concepción máquina, Contamination, Contaminación, Développement durable, Sustainable development, Desarrollo sostenible, Faisabilité, Feasibility, Practicabilidad, Industrialisation, Industrialization, Industrialización, Modèle géométrique, Geometrical model, Modelo geométrico, Modélisation, Modeling, Modelización, Moteur combustion interne, Internal combustion engine, Motor explosión interna, Pollution, Polución, Problème agencement, Layout problem, Problema disposición, Propulsion, Propulsión, Prototypage rapide, Rapid prototyping, Prototipificación rápida, Réalité virtuelle, Virtual reality, Realidad virtual, Rétroingénierie, Reverse engineering, Ingeniera inversa, Savoir faire, Know how, Saber hacer, Spécification, Specification, Especificación, Système acquisition donnée, Data acquisition system, Sistema adquisición dato, Véhicule hybride, Hybrid vehicle, Vehículo híbrido, bimodal vehicle, hybrid vehicle, and pollution

In research field of alternative solutions to internal combustion engine vehicles, the Politecnico di Milano has developed a design and manufacturing project for an adaptable electro-mechanical kit intended to transform a city car with endothermic propulsion into a bimodal one, using existent technologies and innovative solutions. This project involves mechanical and electrical competences in order to develop a new transmission parallel to the current endothermic propulsion and its control system. This paper describes, in general, the developed procedure to obtain the final prototype. At first, the requirements and constraints to fulfil a standard transport urban cycle has been established and the vehicle to modify was selected, in this case the Fiat Grande Punto. Next, new components and the required space to their installation have been identified and specified, whilst mechanical components were designed and manufactured. Instruments of reverse engineering and virtual prototyping have been employed to carry out the geometrical models, simulations and layouts and to identify useful spaces in the vehicle. Finally, general modifications, installation of new components, implementation of control and data acquisition system, fine-tuning and check of specifications fulfilment have been carried out. A 30 km range working in electrical mode, with a top speed of 70 km/h, is assured with the developed kit. These results demonstrate the feasibility to implement a forward bimodal propulsion system into a commercial city car with a little invasive commercial kit, and now, the Politecnico is working at its industrialization and implementation to different models of city cars. Regione Lombardia (Regional government in Italy) has funded this project as an investigation oriented to find new solutions to sustainable transport and reduction of environmental pollution.

ENGINEERING, MULTIDISCIPLINARY, fringe projection, laser scanner, 3D reconstruction, proyección de franjas, escaneo láser, and reconstrucción 3D

The rapid prototyping and copying of real 3D objects play a key role in some industries. Both applications rely on the generation of appropriated computer aided manufacturing (CAM) files. These files represent a set of coordinates of an object and can be understood by a computer numerically controlled (CNC) machine. Non-contact techniques, like laser scanning and fringe projection, are among the possibilities for obtaining such CAM files. In this work, a comparison between the two aforementioned non-contact techniques is presented. The comparison is made based on their performance as candidates for generating CAM files of objects of high reflectivity and maximum lateral dimensions of the order of 15 mm The parameters tested are the quality of the 3D reconstruction, the processing time, and the possibility of these being implemented in industrial scenarios, among others. Under the scope of these parameters, it is concluded that laser scanning offers superior performance for the kind of objects here considered. The techniques are evaluated with dental pieces in order to validate these methodologies in the rapid prototyping and copying of teeth.
La generación rápida de prototipos y la copia de objetos 3D reales desempeñan un papel clave en algunas industrias. Ambas aplicaciones se basan en la producción de archivos apropiados de fabricación asistida por computadora (CAM). Estos archivos representan un conjunto de coordenadas del objeto y que pueden ser entendidos por máquinas de control numérico (CNC). Técnicas de no contacto, como el escaneo láser y la proyección de franjas, se cuentan entre las posibilidades de generar los archivos CAM. En este trabajo se presenta una comparación entre las dos mencionadas técnicas de no contacto, sobre la base de su desempeño como candidatos para la generación de archivos CAM de objetos con dimensiones laterales máximas del orden de 15 mm y alta reflectividad. Los parámetros de prueba son la calidad de la reconstrucción 3D, el tiempo de procesamiento, la posibilidad de ser aplicado en los escenarios industriales, entre otros. En el marco de aplicación de estos parámetros se concluye que el escaneo láser ofrece un rendimiento superior para el tipo de objetos aquí considerados. Las técnicas son evaluadas con piezas dentales para la validación de estas metodologías en la generación rápida de prototipos y copiado de dientes.

ENGINEERING, MULTIDISCIPLINARY, Power measurement, Power quality, Power electronics, Complexity theory, Chaos, Power Inverter, Medida de potencia, Calidad de la Potencia, Electrónica de Potencia, Teoría Compleja, Caos, and Inversor de Potencia

This paper shows the behavior of a three-phase power converter with resistive load using a quasi-sliding and a chaos control techniques for output voltage regulation. Controller is designed using Zero Average Dynamic (ZAD) and Fixed Point Inducting Control (FPIC) techniques. Designs have been tested in a Rapid Control Prototyping (RCP) system based on Digital Signal Processing (DSP) for dSPACE platform. Bifurcation diagrams show the robustness of the system. Chaos detection is a signal processing method in the time domain, and has power quality phenomena detection applications. Results show that the phase voltage in the load has sinusoidal performance when it is controlled with these techniques. When delay effects are considered, experimental and numerical results match in both of stable and transition to chaos zones.
Este documento presenta el desempeño de un inversor de potencia con carga resistiva usando una técnica de control cuasi deslizante y una técnica de control de caos para la regulación de la tensión de salida. El controlador se diseño usando técnicas de Dinámica de Promedio Cero (ZAD) y Punto Fijo de Control de Inducción (FPIC). Los diseños han sido probados en un sistema de Prototipado Rápido de Control (RCP) basado en un Procesador Digital de Señales (DSP) para la plataforma dSPACE. Los diagramas de bifurcaciones muestran la solides del sistema. La detección de caos se realiza por un método de procesamiento de señales en el dominio del tiempo, y tiene aplicaciones en detección de fenómenos de calidad de la potencia. Los resultados muestran que la tensión de fase de la carga tiene desempeño sinusoidal cuando se controla con las técnicas mencionadas. Cuando se consideran los efectos de retraso, los resultados simulados y experimentales coinciden en ambos casos en zonas estables y de transición a caos.

ENGINEERING, MULTIDISCIPLINARY, HIL, Sistema de control, FPGA, Control system, and Hardware-in-the-Loop

Los sistemas de prototipado rápido son ampliamente usados en el desarrollo de productos en diferentes industrias, ya que permite configurar prototipos iniciales, probarlos bajo condiciones reales y optimizarlos con efectividad en tiempo y costo, sin mayor desarrollo de hardware. Con el concepto de Hardware-in-the-loop (HIL), se pueden emular condiciones de operación de un sistema real, llevándolo a un modelo matemático embebido en un sistema electrónico. Este trabajo muestra la implementación de una planta térmica en una FPGA que emula el comportamiento real y permite evaluar los alcances y beneficios de la técnica HIL. Por otro lado, se diseñó un controlador tipo PID en el software LabView®, que reguló la dinámica de la planta embebida usando comunicación serial. Se hizo una comparación entre el experimento y una simulación en Matlab® Simulink para validar el desempeño del sistema con los parámetros de diseño.
Rapid prototyping systems are widely used in product development in the different industries. They provide the ability to set up the initial prototypes, test them under real conditions, and optimize them time- and cost-effectively, without extensive hardware development. Following the Hardware-in-the-loop concept, the operation conditions of a real system can be emulated by means of a mathematical model, embedded in an electronic device. This paper shows a thermal plant implementation in a FPGA, which emulates the real behavior and allows to assess the scope and benefits of HIL technique. On the other hand, a PID controller was designed in LabView® to regulate the dynamics of the embedded plant by serial communication. A comparison was made to validate the system performance based on the design parameters.