ENABLING HARDWARE TECHNOLOGIES FOR AUTONOMY IN TINY ROBOTS: CONTROL, INTEGRATION, ACTUATION

The last two decades have seen many exciting examples of tiny robots from a few cm3 to less than one cm3. Although individually limited, a large group of these robots has the potential to work cooperatively and accomplish complex tasks. Two examples from nature that exhibit this type of cooperation are ant and bee colonies. They have the potential to assist in applications like search and rescue, military scouting, infrastructure and equipment monitoring, nano-manufacture, and possibly medicine. Most of these applications require the high level of autonomy that has been demonstrated by large robotic platforms, such as the iRobot and Honda ASIMO. However, when robot size shrinks down, current approaches to achieve the necessary functions are no longer valid. This work focused on challenges associated with the electronics and fabrication. We addressed three major technical hurdles inherent to current approaches: 1) difficulty of compact integration; 2) need for real-time and power-efficient computations; 3) unavailability of commercial tiny actuators and motion mechanisms. The aim of this work was to provide enabling hardware technologies to achieve autonomy in tiny robots. We proposed a decentralized application-specific integrated circuit (ASIC) where each component is responsible for its own operation and autonomy to the greatest extent possible. The ASIC consists of electronics modules for the fundamental functions required to fulfill the desired autonomy: actuation, control, power supply, and sensing. The actuators and mechanisms could potentially be post-fabricated on the ASIC directly. This design makes for a modular architecture. The following components were shown to work in physical implementations or simulations: 1) a tunable motion controller for ultralow frequency actuation; 2) a nonvolatile memory and programming circuit to achieve automatic and one-time programming; 3) a high-voltage circuit with the highest reported breakdown voltage in standard 0.5 μm CMOS; 4) thermal actuators fabricated using CMOS compatible process; 5) a low-power mixed-signal computational architecture for robotic dynamics simulator; 6) a frequency-boost technique to achieve low jitter in ring oscillators. These contributions will be generally enabling for other systems with strict size and power constraints such as wireless sensor nodes.

The Repellent DEET Potentiates Carbamate Effects via Insect Muscarinic Receptor Interactions: An Alternative Strategy to Control Insect Vector-Borne Diseases.

International audience

Can open access repositories and peer-reviewed journals coexist?

It is often assumed that open access repositories and peer-reviewed journals are in competition with each other and therefore will in the long term be unable to coexist. This paper takes a critical look at that assumption. It draws on the available evidence of actual practice which indicates that coexistence is possible at least in the medium term. It discusses possible future models of publication and dissemination which include open access, repositories, peer review and journals. The paper suggests that repositories and journals may coexist in the long term but that both may have to undergo significant changes. Important areas where changes need to occur include: widespread deployment of repository infrastructure, development of version identification standards, development of value-added features, new business models, new approaches to quality control and adoption of digital preservation as a repository function.

Integración de Arbotix, Raspberry Pi y motores Dynamixel Ax-12+ para un robot humanoide que busca y patea pelotas

En este artículo se presenta a DeBuPa (Detección Búsqueda Pateo) un humanoide de tamaño pequeño (38 cm de alto) construido con las piezas del kit Bioloid. Del kit se ha excluido la tarjeta CM-510 para sustituirla por la tarjeta controladora Arbotix, que será la que controle los 16 motores Dynamixel Ax-12+ (para mover al robot) y 2 servomotores analógicos (para mover la cámara). Además se ha agregado un mini computador Raspberry Pi, con su cámara, para que el robot pueda detectar y seguir la pelota de forma autónoma. Todos estos componentes deben ser coordinados para que se logre cumplir la tarea de detectar, seguir y patear la pelota. Por ello se hace necesaria la comunicación entre la Arbotix y la Raspberry Pi. La herramienta empleada para ello es el framework ROS (Robot Operating System). En la Raspberry Pi se usa el lenguaje C++ y se ejecuta un solo programa encargado de captar la imagen de la cámara, filtrar y procesar para encontrar la pelota, tomar la decisión de la acción a ejecutar y hacer la petición a la Arbotix para que dé la orden a los motores de ejecutar el movimiento. Para captar la imagen de la cámara se ha utilizado la librería RasPiCam CV. Para filtrar y procesar la imagen se ha usado las librerías de OpenCV. La Arbotix, además de controlar los motores, se encarga de monitorizar que el robot se encuentre balanceado, para ello usa el sensor Gyro de Robotis. Si detecta un desbalance de un cierto tamaño puede saber si se ha caído y levantarse.

Controle de sistema não linear de separação gás/líquido sob ação de efeitos transientes fluídicos por sliding control

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Mecânica, 2015.

Sistema de conmutación y control de llamadas basado en OpenBTS y Asterisk

El presente trabajo empleó herramientas de hardware y software de licencia libre para el establecimiento de una estación base celular (BTS) de bajo costo y fácil implementación. Partiendo de conceptos técnicos que facilitan la instalación del sistema OpenBTS y empleando el hardware USRP N210 (Universal Software Radio Peripheral) permitieron desplegar una red análoga al estándar de telefonía móvil (GSM). Usando los teléfonos móviles como extensiones SIP (Session Initiation Protocol) desde Asterisk, logrando ejecutar llamadas entre los terminales, mensajes de texto (SMS), llamadas desde un terminal OpenBTS hacia otra operadora móvil, entre otros servicios.

Relación del Control Glucémico, Función Cognitiva y las Funciones Ejecutivas en el Adulto Mayor con Diabetes Tipo 2: revisión Sistemática

Objetivo: Revisar la evidencia disponible que demuestre la relación que existe entre el control glucémico, función cognitiva y las funciones ejecutivas en el AM con DT2. Métodos: La búsqueda de la literatura se realizó en idioma inglés y español, en 14 bases de datos, Open acces, y en el buscador Google. En base al modelo propuesto por Cooper (2007), para la síntesis de la literatura. Los estudios fueron evaluados para su validez, a través de la guía CASPe para estudios de casos y controles. Resultados: Se analizaron 11estudios de correlación, el 100% de los estudios mostró relación del control glucémico con el deterioro cognitivo y la función ejecutiva en AM con DT2. Los estudios concuerdan que los AM con DT2 presentan deterioro cognitivo, comparado con los AM sin DT2, por lo tanto existe déficit en el AM al realizar las funciones ejecutivas. Conclusiones: Según la evidencia disponible existe una relación significativa en el control glucémico y el deterioro cognitivo en el AM con DT2, así mismo un menor desempeño en la movilidad funcional y la fluidez verbal.

Mimicking the behaviour of idiotypic AIS robot controllers using probabilistic systems

Previous work has shown that robot navigation systems that employ an architecture based upon the idiotypic network theory of the immune system have an advantage over control techniques that rely on reinforcement learning only. This is thought to be a result of intelligent behaviour selection on the part of the idiotypic robot. In this paper an attempt is made to imitate idiotypic dynamics by creating controllers that use reinforcement with a number of different probabilistic schemes to select robot behaviour. The aims are to show that the idiotypic system is not merely performing some kind of periodic random behaviour selection, and to try to gain further insight into the processes that govern the idiotypic mechanism. Trials are carried out using simulated Pioneer robots that undertake navigation exercises. Results show that a scheme that boosts the probability of selecting highly-ranked alternative behaviours to 50% during stall conditions comes closest to achieving the properties of the idiotypic system, but remains unable to match it in terms of all round performance.

On-demand generation and removal of alginate biocompatible microvalves for flow control in microfluidics

[EN] This paper describes, for the first time, the use of alginate hydrogels as miniaturised microvalves within microfluidic devices. These biocompatible and biodegradable microvalves are generated in situ and on demand, allowing for microfluidic flow control. The microfluidic devices were fabricated using an origami inspired technique of folding several layers of cyclic olefin polymer followed by thermocompression bonding. The hydrogels can be dehydrated at mild temperatures, 37◦C, to slightly open the microvalve and chemically erased using an ethylenediaminetetraacetic acid disodium salt (EDTA) solution, to completely open the channel, ensuring the reusability of the whole device and removal of damaged or defective valves for subsequent regeneration.

Control para sistemas LPV basado en la parametrización de controladores estabilizantes

Este trabajo se enfoca en el estudio del control de sistemas Multi-Entrada Multi-Salida (MIMO) Lineales con Parámetros Variantes en el Tiempo (LPV). Los parámetros son medibles y permanecen dentro de cotas conocidas. El control por retroalimentación de salida garantiza estabilidad cuadrática (QS) y desempeño, mediante el Teorema de los vértices y el Lema de Cota Real (BRL). Se proponen condiciones para que el sistema retroalimentado sea convexo cuando se utilizan controladores estabilizantes en cada vértice. El controlador LPV resulta de la interpolación de estos controladores, y se estudia la relación entre la estabilidad y el desempeño del control de los vértices, y la estabilidad y desempeño del sistema LPV. Además, se da una forma explícita del parámetro libre de la Parametrización de Todos los Controladores Estabilizantes (PTCE) que resuelve un criterio de sensibilidad mezclada cuando se tiene un modelo de incertidumbre aditivo a la salida. Los resultados se aplican a un robot planar rotacional de dos grados de libertad, a un motor de CD y a un sistema de dos masas.

Avaliação da crioinjúria em ovócitos imaturos e maturados in vitro e produção de embriões a partir de ovócitos bovinos vitrificados em Open Pulled Straw (OPS) e Cryotop

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Ciências Médicas, Programa de Pós-Graduação em Ciências Médicas, 2012.

CLARK - Smart Clinic Assistant Robot for CGA

En esta presentación se exponen la arquitectura general y el estado actual de desarrollo del sistema CLARK. Dicho sistema tiene como objetivo el despliegue de un asistente robótico para ayudar a un médico en la realización de procedimientos CGA (Comprehensive Geriatric Assessment), de forma que ciertas tareas, tales como la realización de cuestionarios o pruebas de movimiento, puedan ser realizadas por el robot de forma paralela al resto del procedimiento CGA, aumentando así su eficiencia.

AN ENERGY BASED MINIMUM-TIME OPTIMAL CONTROL OF DC-DC CONVERTERS

Time-optimal response is an important and sometimes necessary characteristic of dynamic systems for specific applications. Power converters are widely used in different electrical systems and their dynamic response will affect the whole system. In many electrical systems like microgrids or voltage regulators which supplies sensitive loads fast dynamic response is a must. Minimum time is the fastest converter to compensate the step output reference or load change. Boost converters as one of the wildly used power converters in the electrical systems are aimed to be controlled in optimal time in this study. Linear controllers are not able to provide the optimal response for a boost converter however they are still useful and functional for other applications like reference tracking or stabilization. To obtain the fastest possible response from boost converters, a nonlinear control approach based on the total energy of the system is studied in this research. Total energy of the system considers as the basis for developing the presented method, since it is easy and accurate to measure besides that the total energy of the system represents the actual operating condition of the boost converter. The detailed model of a boost converter is simulated in MATLAB/Simulink to achieve the time optimal response of the boost converter by applying the developed method. The simulation results confirmed the ability of the presented method to secure the time optimal response of the boost converter under four different scenarios.