Cold-blooded horses find their use at present mainly in tensile work in forest stands. Motion mechanics plays the key role in estimating their potential for performing this activity. Subsequently, it is used in their selection and reproduction. In the process, applied load the horse is working with significantly influences the characteristics of a movement. Therefore, for horses doing tensile work, an objective assessment of their movement mechanics is important, not only during demonstration but also under a changing load. The aim of this study was to prepare and evaluate an experiment for assessing the quantitative characteristics of motion mechanics (step length, action height and running speed) of a cold-blooded horse with no load and with a load of different weight using videographic kinematic analysis. The data obtained were statistically processed to assess changes in step length, action height and running speed depending on the changing load. The results of our experiment showed that the step length decreases with increasing weight of the load. From an average value of 1.94 m at run without a load, it drops to an average value of 1.02 m at a maximum monitored load of 500 kg. A high dependence (r=-0.93) of the step length reduction on the tensile load was found. The dependence is strongly evincible (p<0.001). Changes in action height with increasing load weight are different for the forelimb and rear limb. The forelimb has an almost constant value (~ 0.08m) and no dependence (p=0.977) on the changing weight of the load has been demonstrated. The rear limb shows a strong correlation (p<0.001) to the increasing weight of the load. The correlation coefficient r=0.52 indicates only a slight dependence. This difference can be explained by different function and construction of the limb. The running speed derived from the horizontal marker from the tracking mark on the back is uniform in all observed cases and decreases from 1.95 m.s-1 to 1.19 m.s-1 with increasing weight of the load. The dependence is strongly evincible (p<0.001) and the correlation coefficient of r=-0.94 indicates a strong dependence. The results obtained from the horizontal head velocity component are very well matched to the spine results. The results provided by this method can be an invaluable tool in objective detection of utility and breeding potential of cold-blooded horse in tensile work. Based on these findings, we can recommend further development of videographic kinematic analysis application to objectify the evaluation of quantitative characteristics of motion mechanics for zootechnical and breeding practice.

This thesis comprises a study on the kinematic and force analyses of the overconstrained mechanisms. The scope of the overconstrained mechanisms is too wide and difficult to handle. Therefore, the study is restricted to the planar overconstrained mechanisms. Although the study involves only the planar overconstrained mechanisms, the investigated methods and approaches could be extended to the spatial overconstrained mechanisms as well. In this thesis, kinematic analysis is performed in order to investigate how an overconstrained mechanism can be constructed. Four methods are used. These are the analytical method, the method of cognates, the method of combining identical modules and the method of extending an overconstrained mechanism with extra links. This thesis also involves the force analysis of the overconstrained mechanisms. A method is introduced in order to eliminate the force indeterminacy encountered in the overconstrained mechanisms. The results are design based and directly associated with the assembly phase of the mechanism.

An automatic transmission is a device that is connected to the back of an engine and sends the power from the engine to the drive wheels. Its job is to keep the engine within a certain angular velocity. Although there are many epicyclic-type automatic transmissions in production, the related configuration design methods are still tedious and prone to human error. A simple and analytic methodology needs to be developed. Therefore, the purpose of this research is to present an efficient methodology for the systematic design of the epicyclic gear transmissions for automobiles. First, fundamentals and gear-shifting operations of the four-speed, five-speed and six-speed epicyclic-type automatic transmissions are illustrated to establish the design requirements. Second, based on the kinematic equations of the fundamental geared entities and the corresponding basic gear ratios, a procedure is applied to execute the kinematic and mechanical-efficiency analyses for the automatic transmissions. Third, two simple clutching-sequence synthesis methods are proposed and illustrated. One is based on the speed ratio equations, and another is based on the lever diagram. Next, a planar-graph representation is presented to arrange the desired clutches for each possible clutching sequence into the epicyclic gear mechanism. Then, the number of teeth of each gear is synthesized from assigning two or three desired speed ratios by the analytic method. Finally, a computer-aided design program for the clutching-sequence synthesis is developed with the considerations of the design requirements. With the above methods, the systematic designs of the 204 epicylic gear mechanisms are given for demonstrating the feasibility of the proposed methodology. The result of this work shows that the seven-link two-DOF epicylic gear mechanisms, the eight-link two-DOF Ravigneaux gear mechanism, and the nine-link two-DOF parallel-connected epicylic gear mechanisms could reach four-, six-, and six-forward speeds at most, respectively.

¡@An automatic transmission that is a transmission device between the engine and drive wheel, offers the vehicle while increasing and decreasing the speed mainly. Its job keeps the engine within a certain working rotational speed range.¡@Although there are many epicyclic-type automatic transmissions in production, the related design methods of lever diagram is not well developed.¡@Thus, the purpose of this research is to develop a systematic design of the epicyclic gear transmissions for automobiles with lever diagrammatical methodology.¡@First, fundamentals and gear-shifting operations of the four-speed and six-speed epicyclic-type automatic transmissions are illustrated to establish the design requirements.¡@Second, based on the basic theories of lever diagram, a procedure is applied to kinematic analysis for automatic transmission existed, and set up composite lever diagrams of 13 two-DOF seven-link epicyclic gear mechanisms and 190 two-DOF nine-link epicyclic gear mechanisms.¡@Next, a general clutching-sequence synthesis of lever diagrammatical method are proposed and illustrated. According to the limit range of lever dimensions established for four and five coaxial components, the clutching-sequences and the ranges of basic gear ratio of the feasible gear trains can be derived.¡@Finally, the planar-graph representation for arranging desired clutch and the number of teeth based on lever dimensions are applied to design six-forward speeds automatic transmission. The result of this work shows that the seven-link two-DOF epicylic gear mechanisms, and the nine-link two-DOF parallel-connected epicylic gear mechanisms could reach four- and six-forward speeds at most, respectively.

This thesis has developed an efficient methodology for automatic kinematic analysis of planar linkages using the concept of modular kinematics. Unlike conventional general purpose kinematic analysis packages where each joint in the mechanism is represented using a set of non-linear constraint equations which need to be solved by some iterative numerical procedure, modular kinematics is based on the original observation by Assur that kinematic state of a mechanism involving large number of links can be constructed out of the kinematic states of patterns of sub chains called modules taken in a given sequence called module sequence which in turn emulates the step by step construction procedure of traditional graphical methods. The position, velocity and acceleration analysis of modules are available in closed form. Kinematic analysis of modules later in the sequence is enabled by those of the ones earlier in the sequence, hence, the kinematic analysis of a mechanism is accomplished without any iterative endeavor by doing the kinematics of the modules as given in the module sequence. [102] classified all modules into three fundamental types namely input, dyad and transformation and also introduced the concept of constraint module for analyzing graphically non-constructible mechanisms within the paradigm of modular kinematics where a small step of numerical search was needed in an over all closed form kinematic formulation. Module sequence for a mechanism using the modules is not unique. Choice of a later module in the sequence depends upon the selection of modules earlier in the sequence. This thesis has presented a systematic approach of identifying all such methods for all the inversions of the mechanism and represented in the form of a module hierarchy or a module tree where each path from root to the leaf node represents a valid module sequence for the kinematic chain in hand. The work also extended the set of modules by adding eight new modules to what has already been used in literature to make it complete in the sense that all planar mechanisms involving revolute, prismatic and pin-in-slot (including circular slots) can be handled. The computational effort involved for analyzing these mechanisms thus depend on the number of constraint modules occurring in succession in the module sequence. However, maximum possible number of constraint modules in any mechanism with up to twelve links is only two. The derivative analysis also uses the same module sequence, but they are always devoid of any iterative steps. During the process of generation of a module sequence, at every stage multitude of modules could be identified for their potential placement in the sequence. But for every module sequence the difference between the number of input modules and that of constraint modules is constant and is equal to the kinematic degrees-of-freedom (d.o.f) of the mechanism. The algorithm presented in this thesis minimizes the number of generalized inputs (and hence extraneous constraints) and thus attempting to identify the simplest of the module sequences. In that sense the module sequences represented in the module tree are all optimal module sequences. The present work introduced the concept of multi phase modular kinematics which enables a large variety of mechanisms, conventionally identified as complex mechanisms, to be solved in closed form. This is achieved through the use of novel virtual link and virtual joints. Virtual link is slightly different from a normal rigid link in the sense that the joint locations on this are functions of some independent parameters. Since, the locations of joints are not fixed even in the local coordinate frame of the virtual link, the relative velocities between joints are not zero, they need to be appropriately accounted in kinematic analysis. The theory presented in the thesis is implemented in a computer program written in C++ on Windows platform and Graphics library (OpenGL) is used to display linkage configurations and simulations. The program takes the data of joints, input pairs, ground link in certain format through a file. Geometric models developed in any of the existing modeling softwares like ProE, Ideas, AutoCad etc. can be imported in VRML format to the links and in case of no geometric models a simple convex 2D geometry is created for each link for the purpose of visualization. Geometric import of links helps not only in understanding the simulations better but also in useful for dynamic analysis, dynamic motion analysis and interference analysis. A complete kinematic analysis (position, velocity and acceleration) is given for a four bar mechanism and illustrated the positional ( configuration) analysis using modular kinematics for several other examples like old-ham, quick-return mechanisms etc. in the current work. Multi-phase modular approach is illustrated using a five bar with floating input pairs, a back actor and a drafter mechanism and the Back actor configuration is shown with the imported link geometries. It is observed in practice that there are many apparently spatial Mechanisms, which are constructed out of symmetric dispositions of planar mechanisms in space. A pseudo spatial mechanism concept is proposed to solve this class of spatial mechanisms, which can actually be analyzed with the effort of solving only one such component. This concept is illustrated with Shaker and Umbrella mechanisms. Possible extensions of the concept for modeling and analysis of more general class of pseudo-spatial mechanisms are also indicated.

L'hétérogénéité inter-patients des altérations motrices consécutives aux lésions cérébrales rend nécessaire le besoin d'individualiser la prise en charge du patient après AVC. Afin d'apporter une thérapie adaptée aux besoins du patient au moment opportun, il est nécessaire de prendre en compte plusieurs considérations théoriques afin de comprendre comment la rééducation influence la plasticité cérébrale. La récupération motrice est un phénomène complexe et non-linéaire, et identifier ses composantes caractéristiques est délicat. Au travers d'une étude observationnelle, nous avons investigué la récupération de la fonction motrice en condition unimanuelle (membre non-parétique, parétique) et bimanuelle chez des patients cérébro-lésés en phase subaigüe, sans interférer sur leur programme de rééducation classique. Nous avons d'abord validé l'analyse cinématique pour l'évaluation motrice des mouvements d'atteinte d'objets après AVC, en complément des tests cliniques. L'analyse cinématique permet de fournir des indicateurs de la récupération en temps réel de manière plus sensible que les échelles cliniques. En condition unimanuelle, la récupération du membre non-parétique progresse avant de se stabiliser après 9-10 semaines après AVC. En condition bimanuelle, la dynamique de récupération des coordinations bimanuelles change 6 semaines après AVC. Ces périodes pourraient être des fenêtres temporelles clés à prendre en compte en établissant des protocoles de rééducation. L'identification complète et précise de ces patterns naturels de récupération après AVC pourrait permettre de mieux comprendre les réseaux nerveux spécifiques qui sous-tendent les altérations du membre supérieur. A partir de ces indications cliniques prometteuses, proposer une rééducation adaptée au patient et au meilleur moment devient le challenge des travaux futurs. / Poststroke characteristics vary significantly between patients and over time, necessitating the introduction of individualized care. To provide to patients an appropriate and timely therapy, theoretical considerations must be taken into account to understand how a therapy may influence underlying neuroplasticity. Motor recovery is a nonlinear and complex function of time, and identifying its representative features remains intricate. Through observational analysis, we investigated in this thesis the time-related changes in unimanual (nonparetic, paretic upper-limb) and bimanual motor function in subacute poststroke patients, without interfering with standard rehabilitation. Overall, our results firstly validated the relevance of kinematics to assess recovery of reaching movements following stroke, in complement to clinical scores. Kinematics provides accurate real-time indicators of patients' recovery in a more sensitive way to current clinical scales. In unimanual reaching, motor function of nonparetic upper-limb recovered and then leveled off 9-10 weeks poststroke. In bimanual reaching, the dynamic of the recovery pattern of between-hands coordination changed after 6 weeks poststroke. These time-windows might be key periods to consider into designing rehabilitation protocols. Our results contribute to a better understanding of the natural pattern of motor recovery poststroke and could be of interest to understand specific neural network underlying upper-limb impairment. From these promising therapeutic guidelines, next challenge in future research includes tailoring rehabilitation training to patients at the most opportune time.

Human movements are remarkably adaptive, such that we are capable of completing movements in a novel environment with similar accuracy to those performed in a typical environment. Our ability to perform in these environments involves accurate processing of sensory feedback for online and offline control. These processes of control have been widely studied for well learned actions, but not for actions in a novel visuomotor environment. In two experiments, we examined control processes underlying reaches when participants were first introduced to a visuomotor rotation (Experiment 1) and then following visuomotor adaptation (Experiment 2). All participants completed 150 reach training trials when (1) a cursor accurately represented their hand motion (i.e., aligned cursor) and (2) a cursor was rotated 45 degrees clockwise relative to their hand motion (i.e., rotated cursor). In Experiment 1, we sought to determine if the control processes underlying movements in typical and novel visuomotor conditions were comparable. Participants (n = 16) received either continuous visual feedback or terminal visual feedback regarding movement endpoint during reach training. Analyses revealed that participants were able to demonstrate similar outcomes (i.e., movement time and endpoint errors) regardless of visual or cursor feedback, but also demonstrated more offline control (i.e., took more time planning and were less consistent in initiating their movements) when reaching with a rotated cursor compared to an aligned cursor, even at the end of training. Together, the results suggest a greater contribution of offline control processes and less effective online corrective processes when reaching in a novel environment compared to when reaching in a typical environment. In attempt to promote online corrective processes, participants (n = 16) in Experiment 2 first completed the training trials with continuous visual feedback and then completed an additional 45 reaches under (1) slow movement time (i.e., Slow MT: 800-1000 ms) and (2) fast movement time (i.e., Fast MT: 400-500ms) constraints. Results showed a shift to online control (i.e., greater endpoint accuracy) when reaching with an aligned and rotated cursor, when sufficiently more time was provided (i.e., Slow MT). Specifically, participants were able to more effectively utilize visual feedback for online control under the Slow MT constraint compared to when reaching quickly (i.e., Fast MT). Together, these experiments demonstrate a flexibility in control processes underlying reaches with rotated visual feedback of the hand. In that reaches first engage in offline control processes during adaptation to a visuomotor rotation, and then shift to online corrective processes following visuomotor adaptation.

This work thesis is dealing with planar mechanisms. It?s concentrated on definition the topic, enumeration methods of mathematical description of mechanisms and occasion of simulation with usage information technology. It?s going mainly on GeoGebra program, in which were created most of schemes and models mechanisms. Created models are recorded on attached CD. Important charter of this theses are mechanisms used to draving planar curves, ending with mechanisms used to drawing straight line.

Made available in DSpace on 2016-06-02T20:19:08Z (GMT). No. of bitstreams: 1 DissRPC.pdf: 2420716 bytes, checksum: 1cbc22f0545ae9f69283830e98fee60e (MD5) Previous issue date: 2004-03-10 / Financiadora de Estudos e Projetos / The aim of this work was to investigate the influence of body posture during reaching movements in four healthy, four-month-old infants. Experimental conditions consisted of presenting two toys alternately, at the infant s midline and shoulder levels and midway between the infant s shoulder and wrist. After the reaching, the toy was taken away and given back again for a period of two minutes (for each toy) or until the infant reached for it a total of ten times. This procedure was repeated at the supine posture (0º), a reclined posture (45º) and a sitting posture (70º). We randomized this order these positions. The results were recorded on video and analyzed using the Dvideow system for the purpose of checking the kinematics of the angle of the shoulder (flexion/extension and abduction/aduction) and elbow flexion/extension). Also, we analyzed the rectitude index (the distance traveled by the hand during a reaching movement divided by the distance between the starting and the end points), time (in seconds) in each of the three positions, as well as the frequency of reaching unimanually and bimanually. The statistical method used for the rectitude index was t-Student test and for the frequency of reaching was the analysis of variance (ANOVA). From the results showed that there were differences between the frequency of reaching unimanually and bimanually (p-value=0,0341) in sitting posture. The frequency of reaching was more in sitting posture than in supine posture. In relation to the rectitude index, the test showed a significant difference between the supine and reclined postures (p-value=0,001) and the supine and sitting postures (p-value=0,001). The infants spent the same time reaching in the tree postures. When analyzing the angles, only two babies used the same movement pattern for the three positions. We concluded that, the age of 4 months, reaching does not follow a stable pattern, which can be modified by the position of the infant. Each infant has its own intrinsic dynamics and reacts in different ways to the environmental restrictions imposed by different body positions. / O presente estudo teve como objetivo investigar a influência da postura corporal na execução do movimento de alcance em quatro lactentes a termo, saudáveis, com idade de 4 meses de vida. A condição experimental consistia na apresentação de dois brinquedos, alternadamente, na altura dos ombros dos lactentes. Após o alcance, o brinquedo era retirado e apresentado novamente, durante um período de dois minutos para cada brinquedo ou até que o lactente realizasse 10 alcances. Este procedimento foi repetido nas posturas supina (0º), reclinada (45º) e sentada (70º), sendo a ordem escolhida de forma aleatória. As avaliações foram filmadas e analisadas pelo sistema Dvideow, com objetivo de verificar o comportamento das variáveis cinemáticas de ângulo de ombro (flexão/extensão e abdução/adução) e cotovelo (flexão/extensão), índice de retidão (distância percorrida pela mão durante o alcance dividido pela distância entre os pontos de início e fim) e tempo (segundos) em cada uma das três posições, além da freqüência de alcances unimanuais e bimanuais. O método estatístico empregado para o índice de retidão foi o teste t-Student e para a freqüência de alcances, a análise por variância (ANOVA). A partir dos resultados obtidos constatamos que houve diferença entre a freqüência de alcances unimanuais e bimanuais (p=0,0341) na postura sentada. A freqüência de alcances na postura sentada foi maior que na supina (p=0,038). Em relação ao índice de retidão, o teste indicou diferença significativa entre as posturas supina e reclinada (p=0,001) e entre supina e sentada (p=0,002). Os lactentes gastaram o mesmo tempo no alcance nas 3 posturas. Na análise dos ângulos, apenas dois lactentes usaram o mesmo padrão motor para as três posições. Baseando-se na abordagem dos sistemas dinâmicos, verificamos que o alcance ainda é um padrão instável de comportamento, o qual pode ser modificado pela posição do lactente. Cada lactente possui uma dinâmica intrínseca e responde de maneiras diferentes à restrição do ambiente imposta por meio das diferentes posições do corpo.

The aim of this research is to bridge the gap between CAD modeling and kinematic analysis packages by extracting kinematic information directly from part genometries. It will relieve the designers from the tedious task of specifying assembly constraints and specifying redundant information for creating kinematic models. Automatic generation of kinematic assembly models is achieved by characterizing the lower kinematic pairs: cylindrical, spherical, prismatic, planar and revolute; from the geometries point of view. Based on characterization, the algorithms are developed to recognize these kinematic pairs from a pair of part genometries. The combinations of primitive genometric entities: vertices, edges and faces; forming point, line, arc and surface contacts are studied. The signature geometry is found to be associated with each type of joint. The contacts are analysed for restraining the relative motion between a pair of parts. Based on this, the form closure conditions are derived for surface, line, arc and point contacts for each type of joint. The algorithms are developed to automatically recognize these joints and to assemble them into a kinematic assembly model represented as a graph. The strength and novelty of the present procedure is that kinematic pairs can be recognized for conforming as well as non conforming genometries. A Visual Basic for Application (VBA) for Solid Works has been developed using Application Programming Interface (API) for user interaction. The part genometries can be in any 3D solid modeling neutral file format (.sat, .igs, etc) or some of the native formats of CAD softwares supported by Solid Works. The regions of interest can be directly identified through mouse pick on parts using Solid Works Graphical User Interface (GUI). The transformation matrices are derived automatically to position the parts relative to each other. The local interference between part geometries is also considered for checking the validity of the kinematic pair in the assembly. Assembly model is created and represented as a directed graph. The present implementation, built on the ACIS geometry kernel, imports the parts into SolidWorks, specifies the mating regions using a visual Basic interfaces and finally generates the kinematic assembly model as an ADAMS input file complete with part genometries, their mass properties, kinematic joints and their locations.