Tecnologías en la inteligencia ambiental

En este artículo se presenta el término “Inteligencia Ambiental” (AmI) y se describen las distintas tecnologías que posibilitan su desarrollo: la computación ubicua, la comunicación ubicua y las interfaces inteligentes. Enumeraremos las distintas técnicas de localización que se usan en los entornos inteligentes para determinar la ubicación del usuario y poder ofrecerle así los servicios más adecuados. Para comprender mejor las posibilidades de la AmI, también mostraremos sus principales áreas de aplicación.Este trabajo ha sido financiado por el Ministerio de Educación y Ciencia (MEC) de España mediante el proyecto DPI2005-06222 “Diseño, Implementación y Experimentación de Escenarios de Manipulación Inteligentes para Aplicaciones de Ensamblado y Desensamblado Automático” y mediante la beca de postgrado FPU AP2005-1458

PHOTONICALLY SINTERED PZT ENERGY HARVESTER

ABSTRACT This paper reports an Aerosol-Jet printed micro scale Lead Zirconate Titanate (PZT) energy harvester directly sintered on a low melting point substrate in less than 1 msec using photonic sintering technology. To improve the output signal, d33 piezoelectric mode was employed by patterning silver electrodes as an interdigitated structure on top of a PZT film. The size of the device is 15.5 mm × 13.5 mm × 0.2 mm. Up to 2.4 V was measured at 145 MPa tensile bending stress level in the device after poling at 180 °C for 2 hours with an electric field of 30 kV/cm. Using an oscillating stress (~2.5 Hz) of approximately 145 MPa, the power as a function of load was determined by connecting the device with various series resistive loads. A maximal power of 0.1 μW was generated when driving into a 10 MΩ load. A PZT energy harvester, for the first time, is demonstrated which has been directly printed and sintered on a low melting temperature flexible substrate without a film transfer processes. This not only dramatically simplifies the fabrication process, but expands the possible substrate materials for PZT energy harvesters

Designs for a general purpose wearable computer

To provide input and control, wearable computer solutions must replace the familiar desktop interface devices of keyboard and mouse with specialized hardware. While successful wearable input solutions have been developed for domain specific applications, a standard input interface for general purpose wearable computing has yet to emerge. The steep learning curves and unruly hardware of the solutions proposed thus far are one of the factors keeping wearable computing out of the mainstream. This thesis proposes a new input and control approach that increases wearable computing usability by integrating several commonly available devices into a comprehensive system. The proposed system integrates commercial, off the shelf hardware together with generalized software applications that increase the usability and general utility of a wearable computer. The hardware consists of a wearable computer, a clip-on microdisplay eyepiece and a standard PDA running Pocket PC. Through a Bluetooth network, the PDA can wirelessly control the text input (keyboard) and pointer control (mouse) of the wearable computer. The software consists of two applications designed to provide easy access to new content and previously stored data. One application presents a user with a continuous scroll of new content which can be attended to at the user\u27s discretion. The content is dynamically retrieved from any online sources, and can range from news feeds and stock quotes to calendars and weather reports. New content can be added to the user\u27s persistent digital store at any time. The second application, a private peer-to-peer data sharing program called the Tangle, was developed to fuse the user\u27s multiple data sources (home or work computer, wearable computer, PDA) into a single, searchable repository. Tangle also provides easy access to the digital assets of other, trusted Tangle users. Tangle makes it easy for virtually any content that a user encounters while using the system to be easily added to the user\u27s persistent data store

Enhanced Piezoelectric Performance of Printed PZT Films on Low Temperature Substrates

Since piezoelectric effect was discovered in 1880, it has been widely used in micro-actuators, sensors, and energy harvesters. Lead Zirconate Titanate (PZT) is a commonly used piezoelectric material due to the high piezoelectric response. The basic PZT film fabrication process includes deposition, sintering, and poling. However, due to the high sintering temperature (\u3e 800 °C) of PZT, only high melting point material can be served as the substrate. Otherwise, complex film transfer approach is needed to achieve flexible and foldable PZT devices. The exploration is accordingly necessary to realize direct fabrication of PZT films on low melting point substrates without affecting the piezoelectric performance. In order to lower the PZT film sintering temperature, in this work, the effect of the powder size and sintering aid on the sintering temperature was studied. A maskless, CAD driven, non-contact direct printing system, aerosol jet printer, was used to deposit PZT thick films on the substrate. This technique allows creating features without masking and etching processes that are generally required for realizing designed features via conventional deposition approaches. Broadband, sub-millisecond, high intensity flash pulses were used to sinter the PZT films. The role of all sintering parameters was investigated to regulate the sintering quality of the PZT thick films. The photonically sintered films showed much lower substrate temperature increase mainly due to the extremely short pulse duration and temperature gradient through the film thickness. The superior piezoelectric property to thermally sintered group was also obtained. This process significantly shortens the processing duration and dramatically expands the possible substrate materials. It accordingly opens the possibility of processing PZT film directly on low melting point materials. A PZT energy harvester based on this process was directly fabricated on the polyethylene terephthalate (PET) substrate to demonstrate the capability. The relation between the load and the generated power was investigated to obtain the highest output power. Up to 0.1 μW was generated from this flexible energy harvester when connected with 10 MΩ resistive load. Photonic sintering of PZT film also creates the opportunity of processing poling during sintering. Different combinations of the sintering and poling techniques were studied. It was observed that the best piezoelectric property was obtained while performing poling during photonic sintering. Consequently, a new method of printing, sintering, and poling of micro-scaled PZT films was demonstrated in this work resulting in high performance films. This process provides the capability of realizing PZT devices on low temperature substrate, facilitates the fabrication of flexible piezoelectric devices, and enhances the piezoelectric property

CMU Wearable Computers for Real Time Speech Translation

Carnegie Mellon’s Wearable Computers Laboratory has built four generations of real-time speech translation wearable computers, culminating in the Speech Translator Smart Module. Smart Modules use a family of interoperable modules supporting real-time speech recognition, language translation, and speech synthesis. In this paper, we examine the effect of various design factors on performance with emphasis on modularity and scalability. A system-level approach to power / performance optimization is described that improved the metric of (performance / (weight * volume * power)) by over a factor of 300 through the four generations. 1