124 research outputs found

    Bio-Inspired Optic Flow Sensors for Artificial Compound Eyes.

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    Compound eyes in flying insects have been studied to reveal the mysterious cues of vision-based flying mechanisms inside the smallest flying creatures in nature. Especially, researchers in the robotic area have made efforts to transfer the findings into their less than palm-sized unmanned air vehicles, micro-air-vehicles (MAVs). The miniaturized artificial compound eye is one of the key components in this system to provide visual information for navigation. Multi-directional sensing and motion estimation capabilities can give wide field-of-view (FoV) optic flows up to 360 solid angle. By deciphering the wide FoV optic flows, relevant information on the self-status of flight is parsed and utilized for flight command generation. In this work, we realize the wide-field optic flow sensing in a pseudo-hemispherical configuration realized by mounting a number of 2D array optic flow sensors on a flexible PCB module. The flexible PCBs can be bent to form a compound eye shape by origami packaging. From this scheme, the multiple 2D optic flow sensors can provide a modular, expandable configuration to meet low power constraints. The 2D optic flow sensors satisfy the low power constraint by employing a novel bio-inspired algorithm. We have modified the conventional elementary motion detector (EMD), which is known to be a basic operational unit in the insect’s visual pathways. We have implemented a bio-inspired time-stamp-based algorithm in mixed-mode circuits for robust operation. By optimal partitioning of analog to digital signal domains, we can realize the algorithm mostly in digital domain in a column-parallel circuits. Only the feature extraction algorithm is incorporated inside a pixel in analog circuits. In addition, the sensors integrate digital peripheral circuits to provide modular expandability. The on-chip data compressor can reduce the data rate by a factor of 8, so that it can connect a total of 25 optic flow sensors in a 4-wired Serial Peripheral Interface (SPI) bus. The packaged compound eye can transmit full-resolution optic flow data through the single 3MB/sec SPI bus. The fabricated 2D optic flow prototype sensor has achieved the power consumption of 243.3pJ/pixel and the maximum detectable optic flow of 1.96rad/sec at 120fps and 60 FoV.PhDElectrical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/108841/1/sssjpark_1.pd

    NASA Tech Briefs, June 1994

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    Topics covered include: Microelectronics; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery/Automation; Manufacturing/Fabrication; Mathematics and Information Sciences; Life Sciences; Books and Report

    A PCI Express board designed to interface with the electronic phase-2 upgrades of the ATLAS detectors at CERN

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    Nei prossimi 10 anni è in previsione un aggiornamento radicale dell'acceleratore LHC al CERN finalizzato al raggiungimento di più alti valori di luminosità istantanea (oltre \begin{math}5 \times 10^{34}cm^{-2}s^{-1}\end{math}) ed integrata (oltre un fattore 10 rispetto a quella attuale). Conseguentemente, anche i rilevatori degli esperimenti che lavorano al CERN, così come i loro sistemi di acquisizione dati, dovranno essere aggiornati per poter gestire un flusso notevolmente maggiore rispetto a quello utilizzato finora. Questa tesi tratta in particolare di una nuova scheda elettronica di lettura, progettata e testata nel laboratorio di elettronica del Dipartimento di Fisica ed Astronomia dell'Università di Bologna e nel laboratorio di elettronica della Sezione INFN (Istituto Nazionale di Fisica Nucleare) di Bologna. Le motivazioni che hanno indotto lo sviluppo della scheda prototipale sono molteplici. Un primo obiettivo da perseguire è stato quello di aggiornare la versione attuale delle schede elettroniche di acquisizione dati usate oggi nel Pixel Detector dell'esperimento ATLAS, visto che sono anch'esse sotto la responsabilità della sezione INFN di Bologna. Secondariamente, la scheda (nominata Pixel-ROD) è orientata a gestire le esigenze elettroniche che seguiranno l'upgrade di LHC durante la fase 2. La complessità del progetto e l'inerzia intrinseca di una vasta collaborazione come quella di ATLAS, hanno poi indotto lo sviluppo di questo progetto elettronico in largo anticipo rispetto al vero upgrade di fase 2 di LHC, previsto per il 2024. In questo modo saranno anche più facilmente eseguibili eventuali aggiornamenti tecnologici in corso d'opera, senza dover riprogettare da zero un sistema di acquisizione dati completo

    COBE's search for structure in the Big Bang

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    The launch of Cosmic Background Explorer (COBE) and the definition of Earth Observing System (EOS) are two of the major events at NASA-Goddard. The three experiments contained in COBE (Differential Microwave Radiometer (DMR), Far Infrared Absolute Spectrophotometer (FIRAS), and Diffuse Infrared Background Experiment (DIRBE)) are very important in measuring the big bang. DMR measures the isotropy of the cosmic background (direction of the radiation). FIRAS looks at the spectrum over the whole sky, searching for deviations, and DIRBE operates in the infrared part of the spectrum gathering evidence of the earliest galaxy formation. By special techniques, the radiation coming from the solar system will be distinguished from that of extragalactic origin. Unique graphics will be used to represent the temperature of the emitting material. A cosmic event will be modeled of such importance that it will affect cosmological theory for generations to come. EOS will monitor changes in the Earth's geophysics during a whole solar color cycle

    Proceedings of the Fifth International Mobile Satellite Conference 1997

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    Satellite-based mobile communications systems provide voice and data communications to users over a vast geographic area. The users may communicate via mobile or hand-held terminals, which may also provide access to terrestrial communications services. While previous International Mobile Satellite Conferences have concentrated on technical advances and the increasing worldwide commercial activities, this conference focuses on the next generation of mobile satellite services. The approximately 80 papers included here cover sessions in the following areas: networking and protocols; code division multiple access technologies; demand, economics and technology issues; current and planned systems; propagation; terminal technology; modulation and coding advances; spacecraft technology; advanced systems; and applications and experiments

    NASA Tech Briefs, December 2000

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    Topics include: special coverage sections on Imaging/Video/Display Technology, and sections on electronic components and systems, test and measurement, software, information sciences, and special sections of Electronics Tech Briefs and Motion Control Tech Briefs

    NASA Tech Briefs, February 2002

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    Topics include:a technology focus on computers, electronic components and systems, software, materials, mechanics,physical sciences machinery, manufacturing/fabrication, mathematics, book and reports, motion control tech briefs and a special section on Photonics Tech Briefs

    NASA Tech Briefs, March 2002

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    Topics include: a special section on data acquisition, software, electronic components and systems, materials, computer programs, mechanics, machinery/automation, manufacturing, biomedical, physical sciences, book and reports, and a special section of Photonics Tech Briefs

    NASA Tech Briefs, August 1994

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    Topics covered include: Computer Hardware; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences; Life Sciences; Books and Reports

    NASA Tech Briefs, August 1993

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    Topics include: Computer Graphics; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences; Life Sciences; Books and Reports
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