Orientador: Alberto Cliquet Júnior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-18T01:33:18Z (GMT). No. of bitstreams: 1 Alonso_KarinaCristina_M.pdf: 1360725 bytes, checksum: ef5853f896fca8b4d6065d76c5ba5352 (MD5) Previous issue date: 2011 / Resumo: A lesão medular é umas das mais graves e incapacitantes síndromes neurológicas que acomete o ser humano gerando distúrbios motores, sensitivos e neurovegetativos. A cadeira de rodas maximiza a locomoção funcional, a confiança, a independência e o conforto de seu utilizador e, portanto são utilizadas por grande parte dos deficientes físicos. Os indivíduos com lesão medular, aptos a transferir independentemente, possuem, normalmente, um lado preferencial para realizar suas transferências, o que pode gerar desequilíbrios musculares, futuras patologias e/ou lesões nos ombros. O objetivo do estudo foi avaliar a estratégia das transferências de paraplégicos da cadeira de rodas. Participaram do estudo doze sujeitos lesados medulares (T2 a T12), aptos a realizar independentemente a transferência da cadeira de rodas para um tablado com um metro quadrado de área por meio metro de altura. As imagens dos marcadores reflexivos nos pontos anatômicos foram capturadas por seis câmeras de infravermelho ProReflex e processadas através de um software específico (QTrac). Parâmetros cinemáticos do tronco, cabeça e ombros foram avaliados. A comparação das medidas entre os fatores estudados utilizou a ANOVA para medidas repetidas com transformação por postos. O nível de significância adotado para os testes estatísticos foi 5% ou ? 0,05. A pesquisa comparou três fatores: alturas da lesão (alta e baixa), lado de preferência e não para transferir e as duas primeiras fases da transferência (pré-levantamento e levantamento) para duração das fases da transferência, velocidade angular máxima e aceleração angular, índice de curvatura e deslocamento angular de cabeça, porém para deslocamento angular de ombros foi associado à comparação ombro líder e contralateral. A tarefa de transferência foi dividida em três fases: prélevantamento, levantamento e pós-levantamento. A duração das três fases e o índice de curvatura do esterno e da cabeça apresentaram significância estatística (p<0,05) na comparação das fases analisadas. O deslocamento angular dos ombros nos planos (x-y) e (y-z) mostraram significância estatística no efeito altura da lesão e lado da transferência (x-y: p=0.0470; y-z: p=0.0134) e o deslocamento angular da cabeça no plano (x-z) apresentou p=0.0274 no efeito lado da transferência. Os resultados obtidos com o estudo facilitaram a compreensão biomecânica e a descrição das características dos movimentos dos ombros, cabeça e tronco de sujeitos com lesão medular torácica, durante as transferências da cadeira de rodas. Embora, algumas variáveis não tenham atingido valores significativos, observou-se que há diferenças nas estratégias de transferências para as alturas das lesões / Abstract: Spinal Cord injury is one of the most severe and impairing neurological syndrome that causes motor, sensitive and central neural system disorders in humans. Wheelchair maximizes functional locomotion, the reliance, independence and the comfort of theirs users, so it is very used for the persons with physical deficiencies. These subjects usually perform their independent transfers using one side of their preference which may lead to a muscle unbalancing and future injuries. The objective of this study was to assess the wheelchair transfer strategies of paraplegic subjects. Twelve thoracic spinal cord injured subjects participated in this study (T2 to T12), and they were able to independently perform the transfers from a wheelchair to a table with an area of one square meter by half meter height. Images of reflexive anatomic markers were captured by six ProReflex infrared cameras and processed through a QTRac Capture software. Kinematics parameters of the trunk, head and shoulders were assessed. The comparison of the variables among the evaluated factors used ANOVA for repetitive measures with segmented factors. The significance adopted level for statistical tests was 5% or ? 0,05. This research compared three factors (injury height, preference and nonpreference side and phases) for transfer time of phases, maximum angular speed and angular acceleration, curve index and head angular displacement. And also besides the comparisons cited above, the shoulder angular displacement were compared the leading and contralateral shoulders. The transfer task was divided in three phases: pre-lift, lift and post-lift. Three phases duration and curve index had statistical significance (p<0.05). The shoulder angular displacements on x-y and yz plans showed statistical significance on injury height effect and transfer side (x-y: p=0.0470; y-z: p=0.0134) and head angular displacement on x-z plan showed p=0.0274 on transfer side effect. The obtained results with this research make easy the biomechanical understanding and the description of shoulder head and trunk movement characteristics of spinal cord injury subjects on their transfer tasks from wheelchair. Although some variables did not reach significant scores, it was observed that there are differences on transfer strategies for the heights of injuries / Mestrado / Fisiopatologia Cirúrgica / Mestre em Ciências

A kinematically redundant four degrees of freedommanipulator arm, a knuckle boom, is studied. Three joints arerevolute and one linear. Since only three degrees of freedomare needed for positioning, we have one redundant degree offreedom. Three different kinematic control strategies arestudied. One is based on the maximization of velocity (localoptimisation). This strategy is non-repeatable and cansometimes lead to kinematically unfavourable positions. In thesecond strategy, which is based on the maximization of staticlifting capacity (local optimisation), one of the degrees offreedom (the linear joint) is made a function of the toolcentre point position. The third strategy, which is based ondynamic programming (global optimization), calculates theshortest time that is possible for the tool centre point to gofrom one point to another point in the working area. The threestrategies are compared in a simulation study. The simulationsshow the necessary speed requirements for all joints whenperforming straight paths in the manipulator work area. Thesimulations also show the difference in time consumptionsbetween the three control algorithms and also what happens whenthe joints reach their maximum velocity limits. KeywordsManipulator, Kinematic Control, RedundantLanguage

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Four wheeler is one type of the transportation vehicle which be widely used. Good or bad performance of the vehicle steering system has the decisive influence regarding security of the driver operation and the vehicle travel. Therefore, the purpose of this article is to establish the kinematic analysis theories of the vehicle steering system. And an improvement design theory of size synthesis are proposed to develop a set of user-friendly computer aided analysis and design program. At First, this article collects the related literatures and papers to understand the research technique and the design direction of vehicle steering mechanism. Second, establish the location analysis theory, the rotation torque analysis theory, the mechanical advantage theory and other performance¡¦s calculation formula with regard to ¡§Rocker Shaft Type Connecting Rod Vehicle Steering¡¨ and ¡§Rack and Pinion Type Connecting Rod Vehicle Steering¡¨ which are the most widely used. Third, establish a set of user-friendly computer aided kinematic analysis program by using the VB.NET computer programming language. And then propose a systematized movement design procedure, and establish the optimization size synthesis design theory by using the gene calculation method. Afterwards, carry on the sensitivity analysis in view of the each design variable of the steering mechanism with the orthogonal array table, and establish the kinematic improvement design program. Finally, separately aim at the two Vehicle Steering mechanisms, design a new group mechanism¡¦s size, whose steering performance is better than the original mechanism¡¦s size.

The kinematic analysis of an articulated twin body, four-wheel, robotic vehicle is presented. Polaris, a research platform and contending robotic vehicle in the Intelligent Ground Vehicle Competition (IGVC) at Virginia Tech, was redesigned in 2006 to improve the mobility of the vehicle by incorporating an innovative four-bar linkage that connects the two bodies. The new linkage design minimizes vehicle off-tracking by allowing the rear wheels to closely track the path of the front wheels. This thesis will outline the theoretical kinematic model of the four-bar linkage as applied to a twin-bodied, differentially driven vehicle. The kinematic model is validated through computer simulation as well as experimentation on a fully operational robotic vehicle. The kinematic model presented here outlines the foundations for an autonomous, four-wheel drive, multi-body control system and opens avenues for dynamically controlling the tracking of the vehicle's rear body with an actuated linkage configuration. / Master of Science

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Abstract In order to understand ball motions of new ultra-precision ball grinding machine, this study presents an mechanical model using a transparent acrylic container to simulate ball motions. The effects of float material, load, and process condition on the ball grinding characteristics at low shaft speed. The ball motions can be observed by the CCD camera to calculate the ball¡¦s circulation speed , the ball¡¦s spin angular speed and the ball¡¦s spin angle . Furthermore, the kinematic equations of ball motion is derived with different rolling sliding condition. The theoretical values of , , and are compared with the experimental values under pure rolling condition. Results show that the theoretical values are in good agreement with the ball¡¦s spin angular speed, but with larger error for and .This error is still in range of engineer error. Hence, at low shaft speed, contacts between balls and container, or shaft or float are close to the pure rolling conditions. Because the higher friction force between ceramic balls and alumina float, the ball¡¦s circulation speed with alumina float than that with acrylic float since fluid thrusts balls at low shaft speed, the ball¡¦s circulation speed in working fluid than that without working fluid. Since mass of float is light, it can be drive easily. Hence, with increasing the load which also increases the float mass, the float angular speed is decreased and the ball¡¦s circulation speed is also decreased.

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