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A quantitative method was developed to assess the form of agglomerated particles of powdered milk. The method is based on the three-dimensional reconstruction of said particles using a laser displacement sensor (LDS), which allows three-dimensional scanning volume particles to estimate and extract parameters such as sphericity, elongation ratio and flatness, shape factor, and aspect ratio. It was implemented a mechatronic system of two degrees of freedom, comprising a positioning system for rotating the angular agglomerate and linear positioning system to move the LDS. Experimental results allow classifying the agglomerated particles according to their shape parameters.

This paper proposes a methodology to analyze the resolution and variations in the positions of the 3RRR planar parallel mechanism driven by electrical actuators of discrete steps. This methodology consists of graphing and plotting all the possible combinations of angular movements of a three legs mechanism. This generates a “cloud of points” that will be the boundary of the control limits, so as to find the closest trajectory to a straight line. It was found that resolution, accuracy, and the approximation error improves when micro-steps are employed. For this purpose, it is necessary to determine direct and inverse kinematics, in order to calculate the workspace. A prototype was built to validate the methodology proposed.

Resumen In this work, the effect of sugar concentration for second fermentation on effervescence quality of sparkling cider was evaluated by image processing. To elaborate sparkling cider, three levels of sugar were applied (10, 15 and 20 g/L). The evolution of internal pressure was measured once a week. The effervescence characteristics such as: bubbles velocity, bubbles size, crown height and reduction time, were measured. The highest pressure, height crown and lowest size of bubble was obtained with 20 g/L of sugar, meanwhile the highest crown stability was obtained with 15 g/L. The image processing provides an objective and reliable method to evaluate the effervescence characteristics. En este trabajo se evaluo el efecto de la concentracion de azucar para la segunda fermentacion sobre la calidad de la efervescencia en sidra espumosa medida por analisis de imagenes. Para la elaboracion de la sidra espumosa se aplicaron tres concentraciones de azucar (10, 15 y 20 g/L). La evolucion de la presio...

Este documento presenta una técnica novedosa para el monitoreo en línea del desgaste de una herramienta de fresado. El desgaste es estimado directamente a partir de un sensor de proximidad de fibra óptica (SPFO) con características de alta resolución y alto ancho de banda. El SPFO proporciona una medida de la distancia entre su extremo y el perfil de la herramienta. La principal contribución de este trabajo es la aplicación del SPFO para monitorear en línea el desgaste de una herramienta de fresado. Puesto que la luz emitida por el SPFO proviene de un fotodiodo, esta no produce daño a los ojos, lo que la hace más segura que los sensores de desplazamiento de tipo láser. Esta técnica permite monitorear el desgaste de la herramienta en tiempo real, mientras la herramienta gira, con una precisión inferior a 1 micra. Se presentan resultados experimentales para una herramienta de fresado vertical de cuatro filos que gira a 300 rpm.A novel technique for on-line wear monitoring of a milling tool is presented. The tool wear is estimated directly from a fiber optic proximity sensor (FOPS) with high resolution and high bandwidth characteristics. The FOPS provides a distance measurement between its probe and the tool profile. The main contribution of this work is the application of FOPS to sense on-line the wear of a milling tool. Since the light emitted by this sensor comes from a photodiode, it does not produce eye damage; this is safer than laser displacement sensors. This technique senses the tool wear in real time, while the tool is rotating, with an accuracy of less than 1 micron. Experimental results are also presented for a four-flank cutting tool rotating at 300 rpm.

Resumen Foams are widely used in food industry and play an important role in texture and flavor of novel food products. Consumer accepts or rejects a product guided frequently only by foam's appearance; foams with stable, small and uniform size bubbles are associated to good flavor and quality. However, food technologists do not have enough tools to characterize foams in an objective and consistent way. This work presents a methodology to characterize foams appearance using image processing techniques on a set of images during a foaming process by air injection. Two kinds of protein-based foams, having different foaming agent concentration, were created to validate this methodology. Foam stability and homogeneity were determined by quantification of two parameters: bubbles number and size. Those parameters were extracted using image-processing techniques. The images were acquired automatically every 10 sec during the drainage phase using a USB camera and then were processed by personal computer. ...

"En este trabajo se evaluó el efecto de la concentración de azúcar para la segunda fermentación sobre la calidad de la efervescencia en sidra espumosa medida por análisis de imágenes. Para la elaboración de la sidra espumosa se aplicaron tres concentraciones de azúcar (10, 15 y 20 g/L). La evolución de la presión interna durante la segunda fermentación fue medida una vez por semana. Se cuantificaron las características de la efervescencia: la altura de corona y tiempo de reducción, diámetro de las burbujas y velocidad de ascenso de las burbujas. Con 20 g/L de azúcar se obtuvo la mayor presión, mayor altura de corona y menor diámetro de burbuja, mientras que con 15 g/L se presentó la mayor estabilidad de la corona. El análisis de imágenes resultó un método objetivo y confiable para la cuantificación de las características de la efervescencia."