Papers by Gregorio Romero
Lecture Notes in Mechanical Engineering, 2020
Since the beginning of time, the human being has tried to adapt to the environment and has had th... more Since the beginning of time, the human being has tried to adapt to the environment and has had the ability to overcome obstacles in a comfortable and effective way. There exist mechanisms with the ability to move on sandy or rough terrain, where it is very difficult to move or even practically impossible for systems that move by using wheels. Therefore, it is considered vital to study and analyze these kinetic structures in order to provide a series of guidelines aimed at improving their design for application in sandy or desert areas. In this work, and after analyzing the possible advantages of the walking mechanisms, as well as studying other existing ones, we will undertake the design of one of them that can be easily transported. I will be low cost and simple to assemble so it will be able to manufacture the specimens that are needed in the various places where you want to use it. All this taking into ac-count different fundamental parameters.
Sustainability, 2021
A traditional use of bioenergy is the main source of residential energy in developing countries, ... more A traditional use of bioenergy is the main source of residential energy in developing countries, essentially using firewood to cook, boil water or heating affecting people in developing countries. Improved cook stoves are more efficient and less polluting, and there is a need to evaluate different design options to facilitate their adoption. There are different types of very economical improved cookstoves with high combustion efficiency. In Mexico, multiple projects about cook stoves have been carried out, the root of this study being one of them: the Patsari cook stoves. The goal of this project was to modify previous stove designs to align with local people’s habits and traditions. This study shows the importance of including the participation of users in the design of the portable model of Patsari cook stoves, applying the Design Thinking methodology. Many designs or design changes have been carried out on cook stoves by different researchers, but users often do not adapt to them...
Simulation of railways control and protection systems allows the performance of different researc... more Simulation of railways control and protection systems allows the performance of different research tasks at low cost. The possibilities range from the design of the overall system to the planning of the allocation of trackside equipment, checking their influence over the line movements. In this case, simulation of ERTMS / ETCS (European Rail Traffic Management System / European Train Control System) system is especially interesting for its novelty. One properly design simulator would allow to check the technical specifications for finding contradictions that may be introduced during the design of the system, and their subsequent correction. Employment of the simulator for the implementation of the driving and circulation rules is possible too. One simulator would definitely be the essential tool for the final step between the design and the implementation of ERTMS / ETCS. In this paper, one ERTMS / ETCS simulator is presented. This tool is developed under Visual C++, using the power...
This paper presents a development consisting of a virtual reality application used to move, view ... more This paper presents a development consisting of a virtual reality application used to move, view and manipulate mechanisms. These mechanisms can be assembled or disassembled and checked if work properly. A virtual environment can be used and the mechanism can be observed by different ways using a HMD or stereoscopic glasses. The main object of this work is the development of new methodologies for training in mechanical design adapting traditional subjects as Engineering Drawing to the new technologies of visualization and simulation raised in the last years. In order to use these mechanisms in Internet, the program let us obtain a file that can be view with an Internet explorer program. The goal is to develop modules of design engineering through Internet where the three-dimensional and interactive graphics are the most innovative aspect and attractiveness. One of the most important decisions in the development of the project was to select the proper technology of three-dimensional graphics. These graphics had to allow to the interactivity with the user as far as navigation (zoom, rotation and pan) and as far as detection of events so they had to be programmable. In addition characteristics as the small size of file and the possibility of streaming were important. About 800 3D models have been developed where the user can visualize the model from any point of view and size and many of them can interact with him, executing disassemblies or processes for example.
jcsus.fclcz. joaquin.maroto.juandcdios.sanzj(rt.uprn.cs. moving machines, stcering system. l^yWOR... more jcsus.fclcz. joaquin.maroto.juandcdios.sanzj(rt.uprn.cs. moving machines, stcering system. l^yWORDS m d Graph. carth gecbanism. tBS TRACT ftiü papcr prcsents a modcl developed for simulating carth •novini; machines likc whcel loadcrs. The developed modcl is uS£ (i for rea! time simulation and is ineluded in a ful I ituchincry simulator designated for thc Iraining,.
… AND EXHIBITS, HELD …, 2001
Abstract: This paper presents the development by the Railway Research Centre (CITEF) and the Grap... more Abstract: This paper presents the development by the Railway Research Centre (CITEF) and the Graphical Engineering Group (GIG) of a simulator based on virtual reality techniques with training aim: a software tool for the simulation of a railway line and a train equipped ...
This article covers thc analysis and rescarch into a device recent ly dcveloped by thc University... more This article covers thc analysis and rescarch into a device recent ly dcveloped by thc University of Wolvcrhampion (UK). called a 'GP' MTD Meckanica! Thrombeciomy Device. under the direction of Dr G. Pcarcc. This device will improve the process of extracting thrombosis clots in the cerebral arterics. On thc onc hand. thc dcvclopmcnt of thc simulation model of this device is shown by using Bond-Graph formaüsm and, on the other hand. the optimizaron of its performance in the very near future, from thc interpreta! ion of the results.
Computer-Aided Design and system analysis aim to find mathematical models that allow emulating th... more Computer-Aided Design and system analysis aim to find mathematical models that allow emulating the behaviour of components and facilities. The high competitiveness in industry, the little time available for product development and the high cost in terms of time and money of producing the initial prototypes means that the computer-aided design and analysis of products are taking on major importance. On the other hand, in most areas of engineering the components of a system are interconnected and belong to different domains of physics (mechanics, electrics, hydraulics, thermal...). When developing a complete multidisciplinary system, it needs to integrate a design procedure to ensure that it will be successfully achieved. Engineering systems require an analysis of their dynamic behaviour (evolution over time or path of their different variables). The purpose of modelling and simulating dynamic systems is to generate a set of algebraic and differential equations or a mathematical model. In order to perform rapid product optimisation iterations, the models must be formulated and evaluated in the most efficient way. Automated environments contribute to this. One of the pioneers of simulation technology in medicine defines simulation as a technique, not a technology, that replaces real experiences with guided experiences reproducing important aspects of the real world in a fully interactive fashion [iii]. In the following chapters the reader will be introduced to the world of simulation in topics of current interest such as medicine, military purposes and their use in industry for diverse applications that range from the use of networks to combining thermal, chemical or electrical aspects, among others. We hope that after reading the different sections of this book we will have succeeded in bringing across what the scientific community is doing in the field of simulation and that it will be to your interest and liking. Lastly, we would like to thank all the authors for their excellent contributions in the different areas of simulation
Resumen. Según la revisión de 2018 del informe “Perspectivas Mundiales de Urbanización” elaborado... more Resumen. Según la revisión de 2018 del informe “Perspectivas Mundiales de Urbanización” elaborado por la Organización de Naciones Unidas (ONU), hoy en día el 55% de la población mundial vive en áreas urbanas y se prevé que dicha proporción crecerá hasta un 68 % para el año 2050. Las denominadas ciudades inteligentes deben por tanto regirse por los principios de eficiencia y sostenibilidad para que sean lugares no sólo habitables sino saludables para el elevado número de personas que se espera vivan en ellas. Para afrontar este problema se requiere de plataformas multidisciplinares e intersectoriales y la Universidad está llamada a jugar un papel fundamental al respecto. En concreto, los campus universitarios representan el lugar idóneo donde experimentar y evaluar propuestas relativas a eficiencia y sostenibilidad que luego puedan escalarse a las ciudades en las que, muchos de ellos, se integran, surgiendo así el concepto de campus as a living lab. Este artículo presenta el proyecto...
Journal of Biomechanics, 2019
Aspiration thrombectomy is one of the most effective systems for blood clot removal and vessel re... more Aspiration thrombectomy is one of the most effective systems for blood clot removal and vessel recanalization. We present the results of a study involving the modelling and extraction of blood clots in the arteries of the human body using the following computer tools: Bond-Graph methodology for the fluid domain and Multi-Body Simulation for the mechanical domain. The modelling for the mechanical domain focuses on the clot and the distal end section of an aspiration device. Our final model considers an elastic characterization of the blood clot with progressive detachment from the vessel wall. We conclude that the results of such modelling could potentially improve the effectiveness of blood clot removal by reducing the risk of clot fragmentation. Such modelling could also potentially provide an adjunct technique in improving recanalization of arteries over a range of given parameters (mechanical properties of the vessel, mechanical properties of the blood clot, blood clot length, suction pressure, catheter-clot distance, catheter shape, catheter diameter and vessel occlusion).
International Journal on Interactive Design and Manufacturing, 2013
ABSTRACT Multi-projector displays are commonly used for a wide range of applications such as virt... more ABSTRACT Multi-projector displays are commonly used for a wide range of applications such as virtual reality systems, simulators or data visualization where a high resolution image over a large projection surface is required. Such systems are cheap for the resolutions they can provide, can be configured to project images on almost any kind of screen shapes and are easily scalable, but in order to provide a seamless image with no photometric discontinuities they require a precise geometric and colour correction. In this paper, we propose a series of optimization techniques for large projection displays which make the adjustment procedure simpler and faster. Calibration method uses commercial off-the-shelf equipment such as a webcam and an intermediate performance graphics card. Multiple views are used if one camera image can’t cover the entire display with enough resolution. The effect of these optimizations in the calibration of a simulated display formed by 48 projectors are shown.
Journal of Mechanical Engineering and Sciences, 2020
A study involving the removal of blood clots in cerebral vessels by aspiration thrombectomy is pr... more A study involving the removal of blood clots in cerebral vessels by aspiration thrombectomy is presented. A robust design for the distal end geometry of a catheter is obtained that, together with adequate suction conditions, could avoid potential damage in the artery or fragmentation the thrombus. The optimization process of the parameters is undertaken by a Design of Experiments (DOE) that has been prepared based on Robust Design theories. In particular, 27 experiments are run for one factor at 9 levels (catheter geometry) and up to 9 factors at 3 levels. The experiments are formulated with virtual models that are solved with computing tools. Co-simulation between Computer Fluid Dynamics (CFD) and Finite Elements Method (FEM) structural analysis was used to obtain the suction conditions and the behavior of the blood clot during the intervention process. By comparing the results of the 27 experiments, the highest values of the suctioning force are obtained for a hole pattern based c...
Sustainability
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Recently, we have presented some studies concerning the analysis, design and optimization of one ... more Recently, we have presented some studies concerning the analysis, design and optimization of one experimental device developed in the UK - GPTAD - which has been designed to remove blood clots without the need to make contact with the clot itself, thereby potentially reducing the risk of problems such as downstream embolisation. Based on the idea of a modification of the previous device, in this work, we present a model based on the use of stents such as the SolitaireTM FR, which is in contact with the clot itself. In the case of such devices, the stent is self-expandable and the extraction of the blood clot is faciliatated by the stent, which must be inside the clot. Such stents are generally inserted in position by using a guidewire inserted into the catheter. This type of modelling could potentially be useful in showing how the blood clot is moved by the various different forces involved. The modelling has been undertaken by analyzing the resistances, compliances and inertances e...
This paper presents a set of models that compose the electrical power train of a hybrid vehicle, ... more This paper presents a set of models that compose the electrical power train of a hybrid vehicle, used to obtain the requirements of the elements of the power train of this kind of vehicle. These elements are basically the batteries, the thermal engine, the generator and the electrical engine. For the modeling of the thermal engine a complete torque curve is obtained from the maximum torque and the maximum power. The necessary control model is also introduced to rotate at a constant speed the thermal engine and the generator. The electric generator model is composed by a three-phase synchronous machine. So that the generated electrical current is employed to charge the batteries, a full wave three-phase diode bridge is modeled to rectification of such current. An electrochemical cell model will be used for the traction batteries. The voltage at the battery terminals is directly applied to a three-phase inverter that changes the continuous current into three alternating current output...
This paper presents an application designed to train electrical sub-station operators by means of... more This paper presents an application designed to train electrical sub-station operators by means of a virtual reality environment. The application will allow full viewing of any of the substations in the power supply network. It will be possible to navigate into the virtual world and interact with the elements. Each of the elements has behavior laws associated with it, so the complete functionality of the substation can be simulated. Behavior simulation is done using the bond graph technique. This module is built into a larger and more complex computer system composed of the actual sub-station control system, the GIS which defines the topology of the 1 network, and the design system which simulates the behavior of the sub-station. The application automatically updates in the virtual environment any changes to the sub-station's design and allows access, from this environment, to information on every component. The application could transparently replace the actual control system of...
Modelling Simulation and Optimization, 2010
This paper describes the collaboration among students and professors in four different subjects, ... more This paper describes the collaboration among students and professors in four different subjects, to develop multidisciplinary projects. The objective is to simulate the conditions in a company environment. A new methodology based on student interaction and content development in a Wiki environment has been developed. The collaborative server created an 'out of the classroom' discussion forum for students of different subjects, and allowed them to compile a 'project work' portfolio. Students and professors participated with enthusiasm, due to the correct well-distributed work and the easiness of use of the selected platform in which only an internet connected computer is needed to create and to discuss the multidisciplinary projects. Quality of developed projects has been dramatically improved due to integration of results provided from the different teams.
International Journal of Engineering Education, 2015
Creativity is one of the skills of our graduates most demanded by working companies, which is dir... more Creativity is one of the skills of our graduates most demanded by working companies, which is directly linked to problem-solving, innovation, and the creation of new businesses ideas or the patents development. The demand for the creativityskill is ever increasing and appears among the five skills most valued by employers at times when resources are most limited.During the last three years, a set of initiatives has been performing at the Industrial Technologies Degree course, at theUniversidad Polite cnica of Madrid, to enhance creativity as one of the most relevant skills. The goal is clearly to improvethe creative skill of the engineers in the industrial field, having focused the activities carried out on the two major players inthe educational process, i.e. the teaching staff and the students. The paper describes the process followed to gradually bringon board an ever increasing number of teachers committed to developing their student’s creativity.
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Papers by Gregorio Romero