Ciencias Exactas y Ciencias de la Salud
Permanent URI for this collectionhttps://hdl.handle.net/11285/551039
Pertenecen a esta colección Tesis y Trabajos de grado de las Maestrías correspondientes a las Escuelas de Ingeniería y Ciencias así como a Medicina y Ciencias de la Salud.
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- Optimisation of a parametric CAD geometry by means of a genetic algorithm(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2010-08-01) Ríos Soltero, Edgar Francisco; Ríos Soltero, Edgar Francisco; 242246; Cortés Ramírez, Jorge Armando; Galván Rodríguez, Arturo; Elizalde Siller, Hugo Ramón; Tecnológico de Monterrey, Campus Monterrey; Engineering Graduates Programme; Engineering DivisionThis thesis has the aim of optimising a three-dimensional geometry whose dimensions have been previously defined by parameters. Such a definition allows the geometry to change its shape by altering the value of a parameter without the need of directly modifying a geometrical feature (extrusion, protrusion, etc.) itself. In this way, a single value may affect more than one characteristic of the design. Then, the task is to find the best combination of parameters which improve the performance of a design. In here, the optimisation is performed by the computer by means of a genetic algorithm to change the values of such parameters. There is extensive work in the subject of optimising the performance of products by means of genetic algorithms (GA). In this regard, much work has been done by using equations which model their behaviour. The widespread use of computerised technology (for design and analysis) eventually allowed researchers to combine GA with computer-aided design (CAD) and engineering (CAE). This resulted in two major branches of GA-based optimisation of geometries: the agglomeration of finite elements and the combination of geometrical features. In here, a GA is used to iteratively modify (in CAD) and evaluate (in finite-element analysis) a parametric geometry. This geometry corresponds to a mechanism recently developed by the author. The device has both dynamic and static characteristics, however, the evaluations (analyses) performed on the design are purely static. An interface between a numerical analysis software (MATLAB1) and a CAD-CAE suite (CATIA1) is developed. The GA is run within the numerical analysis software and is interfaced to the CAD-CAE suite by means of its application programming interface (API). The results show the feasibility of improving a three-dimensional, feature-based and parametric CAD by means of the variations created by a GA.
- Modeling and Principles of Ionic Polymer-Metal Composite Electroactive Polymers as Actuators for Position Reconfigurable Devices-Edición Única(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2007-12-01) Guzmán Lozano, Josué Florencio; Cortés Ramírez, Jorge Armando; Marie Micheli Masson, Bernard Jean; Valencia Gallegos, Jesús Ángel; ITESM-Campus Monterrey; Ángel Bello, FranciscoThe present work is in the field of functional materials known as electroactive polymers. Electroactive polymers work as a system, enhancing the use of electrical energy to produce displacements and possible mechanical work. An ionic polymer-metal composite is one type of materials. The use of ionic polymer-metal composite actuators is currently a field in development with several areas to be fulfilled by researchers. The objective of this investigation is to develop a constitutive model of the bending deformation of an electroactive ionic polymer-metal composite strip as a response to an electrical input and the ion contents of the material. The constitutive model uses an approach of phase transformation to describe the changes in the cross section of an ionic polymer-metal composite, while modeling the deformations as a bending beam system. For the solution of the constitutive model, the composite material is prepared and characterized. The information about deformation in terms of potential difference, frequency and ionic specie content is gathered through an experimental analysis. The results of this analysis are used to find the parameters in the proposed model. The constitutive model may be applied then to as an engineering tool to propose the design and simulation for a reconfigurable system that uses the IPMC strip with the control variables needed for its repositioning of a device.
- Theory and principles of nickel - titanium shape memory alloy as smart material on the design of cardiovascular stents(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2007-12-01) Varela Jiménez, Manuel Ignacio; Varela Jiménez, Manuel Ignacio; 256743; Cortés Ramírez, Jorge Armando; Gallegos Cázares, Sergio; Florez Calderón, Lucio; Campus Monterrey; Ángel - Bello Acosta, Francisco RománThe changes in manufacturing environment are characterized by aggressive competition on a global scale and rapid changes in process technology. The development of ‘smart’ materials and the need of systems that can be readily reconfigured for a wide range of requirements have become necessary for the future. Nickel – Titanium alloy is a ‘smart’ material with shape memory effect, dominated by a transition between the austenite phase and the martensite structure. The chemical composition and the heat treatment have a significant effect on the transformation temperature of the material; in order to take advantage of the properties of NiTi control of this temperature is essential. One of the applications of NiTi is stents, taking advantage of the NiTi biocompatibility, large recoverable deformation, good fatigue life, superelastic and shape memory properties around body temperature, allowing the development of self-expanding stents. This works has as purpose the development of a constitutive model of NiTi phase transformation from martensite to austenite and the effect of heat treatment on the setting of transformation temperature, to be applied in the design, numerical simulation and laser manufacture of self-expandable stents. Also, considering that the improvement of stents designs and operation by the use of smaller dimensions, functional materials or polymers requires research about modern surface coatings and stent laser manufacturing methods is required, this research also intends to establish the state of art about stents materials, surface coatings and manufacture.
- Theory and Principles of Magnetorheological Fluids as Smart Materials and Their Application on the design of a Mechatronic Leg Prosthesis-Edición Única(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2007-12-01) Valdes Nakamura, Ruth Oseki; Cortés Ramírez, Jorge Armando; Jiménez González, Ricardo; Florez Calderón, Lucio; Campus Monterrey; Angel-Bello Acosta, Francisco RománMagnetorheological (MR) fluids are mainly suspensions of ferromagnetic particles of micrometric size in a carrier liquid. They can be considered smart materials because of their ability to achieve a wide range of viscosities in a fraction of milliseconds under application of a magnetic field. The purpose of the present work is to propose a theoretical basis which supports the rheological behavior of a MR fluid making an analogy with phase transformation, which corresponds to a natural phenomena, it is introduced in a non-explored field because, scientist have not related this natural behavior with a synthetic material such as MR fluid. Some experiment are carried out in order to verify the theory and based on that behavior, MR fluid will be applied in the design of mechatronic leg prosthesis. This work is divided in mainly three specific stages: Chemical formulation and characterization of MR fluid, modeling of the flow phenomena in MR fluids and mechanical design of a mechatronic leg prosthesis using MR fluid. The results of the thesis were a proposed model based on phase transformation, the validation of such model using experimental method and the application in mechatronic leg prosthesis.
- Desarrollo de un Sistema Reconfigurable de Manufactura para Conformado de Productos Laminados Controlado con Actuadores de Aleación con Efecto Memoria y su Formulación Constitutiva(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2004-01-12) de la Garza Giacomán, Rogelio; Cortés Ramírez, Jorge Armando; Martínez Martínez, Manuel; Rodríguez González, Ciro A.; ITESMLa próxima generación de sistemas de manufactura requiere de sistemas flexibles, inteligentes y reconfigurables, esto es debido a las tendencias de manufactura de productos personalizados. La flexibilidad y reconfigurabilidad en el área de conformado está restringida por la rigidez de las matrices y el protocolo de diseño y manufactura, estos protocolos no pueden permitir un avance tecnológico para la reconfigurabilidad cada vez más diversas y numerosas. El objetivo principal de esta investigación es desarrollar un sistema reconfigurable de manufactura para productos laminados, controlado con actuadores de aleación con efecto memoria y su formulación constitutiva. El trabajo se divide en 4 etapas. Primeramente, se tiene la parte introductoria donde se define el problema y se planea el desarrollo del trabajo. En la Segunda parte, se desarrolla un modelo constitutivo para una aleación de NiTi, para actuadores de efecto memoria de acuerdo al cambio de fase microestructural de austenita a martensita y su relación con la curva de esfuerzo deformación. En la tercera parte, se desarrolla el dado reconfigurable al utilizar un material con efecto memoria como actuador para dar la reconfigurabilidad del dado, y se realiza la modelación paramétrica en CAD. Finalmente, se hacen simulaciones computacionales para probar la funcionalidad del mecanismo actuador y un análisis de fuerzas en el perno con varias condiciones. Como resultados se tienen la formulación constitutiva del NiTi, para predecir los esfuerzos y la microestructura, en función de la temperatura y la deformación lo cual es una aportación científica. También se presenta un sistema innovador en un dado reconfigurable, al utilizar material con efecto memoria como actuador. Esto es una innovación tecnológica. Por último, se la funcionalidad mediante la simulación computacional del mecanismo actuador y se validan las condiciones de trabajo comprobar la utilidad de este diseño