KiloHertz Bandwidth, Dual-Stage Haptic Device Lets You Touch Brownian Motion

This paper describes a haptic interface that has a uniform response over the entire human tactile frequency range. Structural mechanics makes it very difficult to implement articulated mechanical systems that can transmit high frequency signals. Here, we separated the frequency range into two frequency bands. The lower band is within the first structural mode of the corresponding haptic device while the higher one can be transmitted accurately by a fast actuator operating from conservation of momentum, that is, without reaction forces to the ground. To couple the two systems, we adopted a channel separation approach akin to that employed in the design of acoustic reproduction systems. The two channels are recombined at the tip of the device to give a uniform frequency response from DC to one kHz. In terms of mechanical design, the high-frequency transducer was embedded inside the tip of the main stage so that during operation, the human operator has only to interact with a single finger interface. In order to exemplify the type of application that would benefit from this kind of interface, we applied it to the haptic exploration with microscopic scales objects which are known to behave with very fast dynamics. The novel haptic interface was bilaterally coupled with a micromanipulation platform to demonstrate its capabilities. Operators could feel interaction forces arising from contact as well as those resulting from Brownian motion and could manoeuvre a micro bead in the absence of vision

Los sistemas de información geográfica: una herramienta tecnológica para identificar la pobreza

This article aims to present the results of a pilot project conducted by the international NGO Institute for Conscious Global Change , in which they analyzed the poverty dimensions in the New York City district of Queens. By using Geographic Information Systems (GIS) technology, a series of maps were created to identify the location of the communities affected by poverty. Finally, with the Geodesign it could be proposed the services that might be necessary to improve the living conditions in the areas previously analyzed.Este artículo pretende mostrar los resultados del proyecto piloto llevado a cabo por la ONG Institute for Conscious Global Change, y cuyo objetivo era analizar las dimensiones de la pobreza en el distrito neoyorquino de Queens. Para ello, usando la tecnología de un Sistema de Información Geográfica (SIG), se elaboraron una serie de mapas que permitieron identificar la localización de las comunidades afectadas por la pobreza. Posteriormente, mediante el Geodiseño, se propusieron qué medidas se podrían implantar en las áreas analizadas, para mejorar las condiciones de vida

Optical trapping and binding

The phenomenon of light's momentum was first observed in the laboratory at the beginning of the twentieth century, and its potential for manipulating microscopic particles was demonstrated by Ashkin some 70 years later. Since that initial demonstration, and the seminal 1986 paper where a single-beam gradient-force trap was realized, optical trapping has been exploited as both a rich example of physical phenomena and a powerful tool for sensitive measurement. This review outlines the underlying theory of optical traps, and explores many of the physical observations that have been made in such systems. These phenomena include 'optical binding', where trapped objects interact with one another through the trapping light field. We also discuss a number of the applications of 'optical tweezers' across the physical and life sciences, as well as covering some of the issues involved in constructing and using such a tool