A Acessibilidade como veículo de inclusão social: proposta de dispositivo computacional para os deficientes visuais da cidade de Natal/RN

This study aims to propose a computing device mechanism which is capable to permit a tactile communication between individuals with visual impairment (blindness or low vision) through the Internet or through a local area network (LAN - Local Network Address). The work was developed under the research projects that currently are realized in the LAI (Laboratory of Integrated Accessibility) of the Federal University of Rio Grande do Norte. This way, the research was done in order to involve a prototype capable to recognize geometries by students considered blind from the Institute of Education and Rehabilitation of Blind of Rio Grande do Norte (IERC-RN), located in Alecrim neighborhood, Natal/RN. Besides this research, another prototype was developed to test the communication via a local network and Internet. To analyze the data, a qualitative and quantitative approach was used through simple statistical techniques, such as percentages and averages, to support subjective interpretations. The results offer an analysis of the extent to which the implementation can contribute to the socialization and learning of the visually impaired. Finally, some recommendations are suggested for the development of future researches in order to facilitate the proposed mechanism.

Controle de atitude e altitude para um veículo aéreo não tripulado do tipo quadrirrotor

A Quadrotor is an Unmanned Aerial Vehicle (UAV) equipped with four rotors distributed on a simple mechanical "X"form structure. The aim of this work is to build and stabilize a Quadrotor aircraft in the roll, pitch and yaw angles at a certain altitude. The stabilization control approach is based on a transformation in the input variables in order to perform a decoupled control. The proposed strategy is based on breaking the control problem into two hierarchical levels: A lower level, object of this work, maintains the desired altitude an angles of the vehicle while the higher level establishes appropriate references to the lower level, performing the desired movements. A hardware and software architecture was specially developed and implemented for an experimental prototype used to test and validate the proposed control approach

Controle de posição com restrição à orientação de um Veículo Aéreo Não-Tripulado tipo Quadrirrotor

Quadrotors aircraft are composed by four propellers mounted on four engines on a cross or x disposition, and, in this structure, the engines on the same arm spin in the same direction and the other arm in the opposite direction. By rotating each helix generates vertical upward thrust. The control is done by varying the rotational speed of each motor. Among the advantages of this type of vehicle can cite the mechanical simplicity of construction, the high degree of maneuverability and the ability to have vertical takeoffs and landings. The modeling and control of quadrirrotores have been a challenge due to problems such as nonlinearity and coupling between variables. Several strategies have been developed to control this type of vehicle, from the classical control to modern. There are air surveillance applications where a camera is fixed on the vehicle to point forward, where it is desired that the quadrotor moves at a fixed altitude toward the target also pointing forward, which imposes an artificial constraint motion, because it is not desired that it moves laterally, but only forwards or backwards and around its axes . This restriction is similar to the naturally existing on robots powered by wheels with differential drive, which also can not move laterally, due to the friction of the wheels. Therefore, a position control strategy similar to that used in this type of robot could be adapted for aerial robots like quadrotor. This dissertation presents and discusses some strategies for the control of position and orientation of quadrotors found in the literature and proposes a strategy based on dynamic control of mobile robots with differential drive, called the variable reference control. The validity of the proposed strategy is demonstrated through computer simulations

Desempenho de um veículo flex em bancada dinamométrica de chassi

Flex-fuel vehicles are equipped with Otto Cycle internal combustion engines and have the capability of functioning with more than one type of fuel, mixed at the same tank and burned in the combustion chamber simultaneously. This sort of motorization is a world pattern due to the scarcity of petroleum, the trade of several types of fuels, technology advances and the restriction imposed to gas emissions to the atmosphere. In Brazil, the Flexfuel vehicles are a reality, specially the ones using fuel with 20 to 25% anhydrous alcohol mixed with gasoline and those that use natural gas or original liquid fuel (gasoline or hydrated ethanol). The Brazilian model Fiat Siena, the object of this present scientific investigation, is equipped with a unique electronic central capable of managing the liquid or gaseous fuels. The purpose of this research was to perform a comparative analysis in terms of performance (in terms of both potency and consumption) of a tetra-fuel vehicle - using a chassis dynamometer, operating with different fuels: common gasoline, premium gasoline, Podium gasoline, ethanol or natural gas. It became necessary to develop a bench of tests and trials procedures, as well as to know the functioning of the electronic management of the vehicle under analysis. The experiments were performed at the automotive laboratory in CTGAS-ER (Center of Gas Technologies and Renewable energies) at the light of Brazilian standard ABNT, NBR 7024: Light on-road vehicles - measurement of fuel consumption. The essay results on specific fuel consumption using common gasoline, premium gasoline and Podium gasoline have shown similar results, both for urban and road driving cycles

Eficácia da utilização de grânulos de argila como veículo para a aplicação aérea de sulfentrazone e isoxaflutole em área de implantação de eucalipto

Realizou-se um experimento em uma área de implantação da cultura do eucalipto no município de São Miguel Arcanjo-SP, com o objetivo de avaliar a eficácia da aplicação aérea de grânulos de argila como veículo dos herbicidas sulfentrazone e isoxaflutole, no controle de plantas daninhas. Foi realizada aplicação aérea dos herbicidas sulfentrazone, nas doses de 500 e 750 g i.a. ha-1, e isoxaflutole, nas doses de 150 e 225 g i.a. ha-1, utilizando-se como veículo grânulos de argila com densidade de 1,05 g cm ³, alta capacidade de absorção (24 mL 100 g-1), alta resistência ao desgaste e tamanho das partículas entre 500 mícrons e 1 mm. Também foram feitas aplicações via líquida dos mesmos herbicidas e doses com um pulverizador convencional, acoplado a um trator. Além desses tratamentos, foi mantida uma parcela testemunha, sem aplicação dos herbicidas. Nas parcelas experimentais foram semeadas as espécies de plantas daninhas Brachiaria decumbens, Ipomoea grandifolia, Merremia cissoides e Panicum maximum, sendo realizadas avaliações visuais de controle aos 75 e 110 dias após a aplicação. em geral, foram observados, nas plantas daninhas avaliadas, resultados de controle semelhantes ou superiores para a aplicação aérea (via grânulos) até 75 DAA e superiores para essa modalidade de aplicação aos 110 DAA, indicando uma extensão no período do efeito do residual dos herbicidas estudados.

Estado da arte da obtenção de crédito de carbono via adoção de veículo elétrico

This paper aims to highlight the state of the art of obtaining carbon credits through the use of electric vehicles. This is one of the solutions to significantly reduce the emission of GHG (Greenhouse Gas) emissions in the case of CO 2, NOx, SOx, and CH 4 (thermochemical reactions arising from the combustion of gasoline with ethanol) in motor vehicles. For this quantitative study was done based on the survey of bibliographic data available and the development of basic calculations considering the car fleet of the Country of Brazil and the CO 2 emissions generated by the same. Thus explaining the considerable gain in air quality and reduction of vectors of greenhouse gases in the case of replacing the current fleet of vehicles combustion of hydrocarbon aliphatic chain, for an eco-efficient fleet consists of electric vehicles and/or hybrids.

O pão (1892-1896): veículo de divulgação literária e instrumento de intervenção na realidade social cearense

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Livros à mão cheia: o livro como veículo de produção acadêmica

O texto discute a importância do livro como modalidade de produção acadêmica. São apresentados argumentos em favor da visão de que periódicos e livros, em diversas áreas de conhecimento, constituem formas de veiculação de produção científica que se complementam no cumprimento de funções relevantes para o desenvolvimento da ciência e para a formação e atualização de profissionais. A metodologia adotada nos últimos anos para a avaliação dos livros produzidos no âmbito da pós-graduação em Psicologia é descrita e comentada.

Análise da falha do suporte de mancal de um eixo cardan utilizado num veículo pesado

Pós-graduação em Engenharia Mecânica - FEG

Desenvolvimento de um computador de bordo para veículo Baja-SAE

The objective of this paper is show the development of an Eletronic Control Unit (ECU) for Baja-SAE vehicles from its requirements to final implementation. An ECU for Baja-SAE vehicles is made of electric and electronic circuits (appropriated to the hostile situations of an off-road competition) able to make important measurements for the running or stand-by vehicle performance. For this development, some concepts were studied: embedded electronics concepts (mainly microcontrollers and data acquisition circuits) and sensoring. Both the studies were made considering the off-road environment. After these initial studies, the elaboration of the basics hardware and software (under simulations) has begun, and this elaboration objectives maximum performance and low implementation cost. After the theorical studies, basic definition of the hardware and software’s architectures and simulations, the printed circuit boards (PCB) were made, as exhaustive tests in these boards for debugging and verify if the boards work well. Once the system was tested in the university, it ran into a regional Southeast competition in 2010, that definitely proved the efficiency of the whole system

Análise e redução de custos e peso em veículo rodoviário de carga reboque linha de eixos

Load transportation in brazilian territory is made difficult by a deficient highway network, result of low maintenance and lack of government supervision. The problem aggravates when we consider the transportation of indivisible loads, mainly because the brazilian highways are not prepared for such task and few companies in Brazil have the necessary equipment suited for this kind of transport. In this dissertation it will be shown the analysis of a specific equipment to transport overweight indivisible loads, called hydraulic modular multi axle trailer. From an existing project (RB.04LE-01), manufactured and homologated in Brazil, it has been studied how the components in this trailer work so it could have been possible to elaborate a new model (RB.04LE-02), with two main objectives: reduction of costs and weight with subsequent increase in the liquid load for roadway transportation. The trailer’s components analyses were made utilizing the theory of fatigue strength of materials and finite element method with the von Misses criteria for a more safety when realizing the calculations

Acurácia da mosaicagem gerada por veículo aéreo não tripulado utilizado na agricultura de precisão

The need for unmanned aerial vehicle (UAV) is a Brazilian reality in the worlds agricultural, once they have models penetrating the market with agrictural purpose. After processing, the images collected by a UAV can generate a mosaic of the study area. For making and georeferencing the mosaic, can be deployed or not ground control points. Thus, the study aimed to compare a mosaic with ground control points and without ground control points generated from images collected by a UAV used primarily for agricultural purposes. The results showed that the quality in the determination of areas and perimeters no presented significant difference with or without the use of ground control points. The mosaic generated without ground control points obtained an average error of 23.7% of the pixel size; with ground control points, the average error was 10.6%, providing an improvement of approximately 50%. Planimetric and altimetric errors, with respect to the ground control points, for the controlled mosaic, reached the order of decimeters, with planimetric accuracy of 12.8 cm, a result considered satisfactory taking into account mainly the purpose of assessed UAV

Otimização do braço inferior da suspensão dianteira do veículo Baja utilizando o método dos elementos finitos

Mass reduction coupled with the mechanical performance in service has been the goal of many projects related to the transport area, considering the advantages that mass reduction can bring. However, make a simple material substitution without design a new geometry to corroborate for the best component performance, often makes the replacement unviable. In this study, it was investigated the advantages of replacing the prototype BAJA SAE front suspension lower arm of Equipe Piratas do Vale de BAJA SAE - Universidade Paulista, Campus Guaratinguetá, actually produced with steel, for a new component made of carbon fiber composite. The new geometry has been developed to provide the best possible performance for this component and your easy manufacturing. The study was done using the 3D modeling tools and computer simulations via finite element method. The first stage of this work consisted on calculation of the estimated maximum contact force tire / soil in a prototype landing after jump at one meter high, drop test in the laboratory with the current vehicle, current front suspension lower arm 3D modeling, finite element simulation and analysis of critical regions. After all current component analysis, a new geometry for the part in study was designed and simulated in order to reduce the component mass and provide a technological innovation using composite materials. With this work it was possible to obtain a theoretical component mass reduction of 25,15% maintaining the mechanical strength necessary for the appropriated component performance when incited

Análise cinemática e dinâmica para conversão de um VW saveiro em veículo elétrico

This work aims to kinematic and dynamic analysis of a VW Saveiro in order to estimate the power requested to the engine with the imposed movement conditions. Thus, the study will be the basis to the specification of the electric engine, on the conversion of the internal combustion vehicle into electric one. First of all, a literature review was done in order to understand the state of the art for this issue and come up with the technical features of the vehicle in question. The next step is the identification and calculation of all forces acting on the prototype in motion, from 0 to 120 km/h, in intervals of 10 km/h, under the defined conditions of path and time. Then, were determined the values of the torque and rotation of the components from the transmission system, as well as the engine power, for each speed range. The results show the most influential forces on the resistence of the movement in each speed range, and the behavior of the torque curve is verified. Finally, it was also analyzed the implementation of pinwheels on the frontal area of the vehicle, in order to convert wind energy into electrical energy to supply the lighting subsystem of the vehicle and the proposal was validated. Limiting the maximum speed of the vehicle to 90 km/h, it was finally concluded that the power of the electric engine should be 40 HP

Projeto mecânico do sistema de transmissão de um veículo Baja

This study aims to determine the best configuration for the new gearbox of the new Baja´s vehicle from Piratas do Vale team, focusing on the gear train, in order to achieve high performance of it. To this end, first some information about the vehicle is gathered to determine the best pair of gears configuration, then calculations about maximum bending stress, fatigue and surface thereof are performed; ; thereafter static simulations are performed using an a appropriated software. Thus this paper shows a satisfactory design of the addressed, besides providing the Baja SAE team consultation material for future use in the project