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rapid prototyping, lost wax process (investment casting), waxes, ABS, Engineering (General). Civil engineering (General), and TA1-2040

Rapid prototyping is a manufacturing process which is different to traditional methods as material is not removed or formed but added to obtain the designed pieces. It is not lust used for manufacturing finished products but in manufacturing tooling for speeding up other manufacturing processes. This paper introduces rapid prototyping as a support technique for the lost wax process (investment casting). It gives a brief description of the different techniques implemented to date and materials used for making articles as part of the lost wax process.

buck converter, DSP, permanent magnet DC motor, controller, hysteresis, rapid control prototyping (RCP), Engineering (General). Civil engineering (General), and TA1-2040

Prácticamente todo desarrollo de ingeniería sobre sistemas de control suele ser analizado mediante simulación para prever su desempeño. Sin embargo, no se debe dejar de tener en cuenta que el destino final del algoritmo será su aplicación en un sistema de tiempo real. Utilizando como herramientas de desarrollo una placa con tecnología DSP y el Simulink con RTW, se pueden realizar simulaciones en tiempo real (es decir, la simulación interactúa con la planta física). Para poder apreciar las considerables ventajas que brindan estas herramientas se ha planteado ensayar un lazo de control de velocidad a un motor de corriente continua de imanes permanentes.

EMI reduction, DSP, power electronic converters, shielding, rapid control prototyping (RCP), Engineering (General). Civil engineering (General), and TA1-2040

En este artículo se presentan los resultados de la aplicación de algunas técnicas de reducción de EMI en convertidores electrónicos de potencia. Las técnicas aplicadas incluyen el apantallamiento de señales de control y de potencia, la separación de las referencias del sistema de potencia de las señales y medidas, la implementación de filtros análogos y la configuración de un adecuado sistema de disparo, de tal forma que se disminuyan al máximo las emisiones tipo IEM. En este artículo se presentan los resultados obtenidos antes y después de aplicar las técnicas de reducción de interferencias. Además los resultados son verificados usando dos técnicas de control en tiempo real RCP (Rapid Control Prototy- ping).

3D printing, mechanical properties, FDM process, ABS, makerbot replicator 2X, Engineering (General). Civil engineering (General), and TA1-2040

3D printing is a manufacturing process that is usually used for modeling and prototyping. One of the most popular printing techniques is fused deposition modeling (FDM), which is based on adding melted material layer by layer. Although FDM has several advantages with respect to other manufacturing materials, there are several problems that have to be faced. When setting the printing options, several parameters have to be taken into account, such as temperature, speed, infill percentage, etc. Selecting these parameters is often a great challenge for the user, and is generally solved by experience without considering the influence of variations in the parameters on the mechanical properties of the printed parts.This article analyzes the influence of the infill percentage on the mechanical properties of ABS (Acrylonitrile Butadiene Styrene) printed parts. In order to characterize this influence, test specimens for tensile strength and Charpy tests were printed with a Makerbot Replicator 2X printer, in which the infill percentage was varied but the rest of the printing parameters were kept constant. Three different results were analyzed for these tests: tensile strength, impact resistance, and effective printing time. Results showed that the maximum tensile force (1438N) and tensile stress (34,57MPa) were obtained by using 100% infill. The maximum impact resistance, 1,55J, was also obtained with 100% infill. In terms of effective printing time, results showed that printing with an infill range between 50% and 98% is not recommended, since the effective printing time is higher than with a 100% infill and the tensile strength and impact resistance are smaller. In addition, in comparing the results of our analysis with results from other authors, it can be concluded that the printer type and plastic roll significantly influence the mechanical properties of ABS parts.