Metodologia para descrição tridimensional do movimento humano a partir de cameras de video não sincronizadas

Orientador: René BrenzikoferDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Educação FisicaResumo: Este trabalho pretende contribuir para o incremento das pesquisas em Biomecânica por meio de uma metodologia para descrição tridimensional de movimentos que seja rigorosa e precisa quanto aos seus resultados, simples quanto à sua implementação, que evite causar constrangimentos à livre movimentação do sujeito estudado e acessível financeiramente. Para que obtenhamos essa descrição necessitamos, no mínimo, de duas vistas do mesmo movimento (filmagem estereoscópica) e que cada ponto de interesse seja observado simultaneamente pelas duas câmeras. O principal problema no uso de câmeras de vídeo padrão na reconstrução de movimentos é a falta de sincronização entre os registros. As causas dessa falta de sincronismo nos registros são o fato de que eles não se iniciam no mesmo instante e a possível diferença de freqüência entre os equipamentos. Para que possamos determinar a posição no espaço dos pontos de interesse a cada instante, primeiramente fazemos medições das imagens destes pontos que obtemos por meio das filmagens. Depois que nossas seqüências de imagens de vídeo foram digitalizadas e estão armazenadas em memória no computador, aplicamos um programa que realiza as medições.... Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digitalAbstract: The aim of this work is to contribute to the development of research in Biomechanics with a methodology for the three-dimensional description of movements. This methodology should be both precise and of simple implementation, it should avoid constraints to the subject studied and be financially affordable. In order to obtain this description we need at least two views of the same movement (stereoscopic filming) and also that each point of interest be simultaneously observed by both cameras. The main problem in the use of standard video cameras is the lack of synchronization between registers. The causes of this lack are (1) the fact that the registers do not start at the same time and (2) the possible frequency mismatch between the machines. To determinate the position of the points of interest in space at each moment, we first measure the images of the points obtained with the filming. Aft'er having digitalized the sequences of video images and having stored them in the computer memory, we run a software which enables measurements.... Note: The complete abstract is available with the full electronic digital thesis or dissertationsMestradoCiencia do EsporteMestre em Educação Físic

INFLUENCE OF YEARS OF SWIM TRAINING ON SEPARATE THORACOABDOMINAL VOLUMES DURING BREATHING

The purpose of this study was to verify the influence of the years of swim training on the separate thoracoabdominal volume variation during breathing using a kinematic analysis. Fifteen male swimmers were analyzed during tidal volume and vital capacity maneuvers. From the 3D coordinates of 30 markers fixed at the trunk the volumes of 4 separate compartments of the trunk (superior thorax, inferior thorax, superior abdomen and inferior abdomen) were calculated in function of time. During tidal volume, the coefficient of variation of the volumes of the superior and inferior abdomen increased with the years of swim training (

SEPARATE TRUNK VOLUMES AND RIBS MOTION CORRELATIONS IN SWIMMERS

The purpose of this study was that to analyze the separate trunk volumes and ribs motion correlations aiming to verify swimmers present better motor coordination or control during breathing. The trunk was represented by 53 markers, attached to the ribs, vertebrae, thorax and abdomen of 13 male swimmers and 10 non-athletes. From the 3D coordinates of the markers, obtained by a kinematical analysis system equipped with 6 digital video cameras (60Hz), in function of time, the rotation angles of the 2nd to the 10th ribs around the quasi-transversal axis and the volumes of 4 separate compartments of the trunk were calculated (superior thorax, inferior thorax, superior abdomen and inferior abdomen). Correlating the curves of ribs rotation angles with the curves of the separate volumes, swimmers presented higher values during vital capacity manoeuvers when the correlation involved the inferior thorax and the superior and inferior abdomen. These results showed a better coordination between the trunk volumes and the ribs motion in the swimmers during vital capacity manoeuvers, suggesting that swimming practice leads to the formation of an optimized breathing pattern when larger efforts are required from the respiratory system

SEPARATE TRUNK VOLUMES AND RIBS MOTION CORRELATIONS IN SWIMMERS

The purpose of this study was that to analyze the separate trunk volumes and ribs motion correlations aiming to verify swimmers present better motor coordination or control during breathing. The trunk was represented by 53 markers, attached to the ribs, vertebrae, thorax and abdomen of 13 male swimmers and 10 non-athletes. From the 3D coordinates of the markers, obtained by a kinematical analysis system equipped with 6 digital video cameras (60Hz), in function of time, the rotation angles of the 2nd to the 10th ribs around the quasi-transversal axis and the volumes of 4 separate compartments of the trunk were calculated (superior thorax, inferior thorax, superior abdomen and inferior abdomen). Correlating the curves of ribs rotation angles with the curves of the separate volumes, swimmers presented higher values during vital capacity manoeuvers when the correlation involved the inferior thorax and the superior and inferior abdomen. These results showed a better coordination between the trunk volumes and the ribs motion in the swimmers during vital capacity manoeuvers, suggesting that swimming practice leads to the formation of an optimized breathing pattern when larger efforts are required from the respiratory system

Analysis of variability in measurements on soccer tactic positions

O objetivo deste trabalho foi analisar a variabilidade na medição de posicionamento tático de jogadores de futebol. Para isto foram feitas 20 análises do primeiro tempo do jogo entre Corinthians e Palmeiras, válido pela Taça Libertadores da América de 1999. Foram registrados os locais em que ocorreram as ações do jogador Vampeta, do Corinthians, através de um “software” que simula um campo de jogo onde são marcados os locais em que jogadores se encontram posicionados em cada uma de suas ações. Após marcadas todas as ações do jogador, foi feita a construção de dois eixos principais, que substituem os locais das ações, para cada vez que o jogo foi analisado. Os autovetores são ortogonais entre si e o ponto de intersecção entre os dois eixos foi centrado nas medianas de X e de Y. O comprimento dos eixos principais foi determinado pelos pontos mais distantes, depois de selecionada a porcentagem dos dados que seriam utilizados na sua construção. Neste caso, os dados foram restritos ao nonagésimo percentil. A variabilidade foi medida pelo intervalo interquartil do BOXPLOT, que é uma medida de dispersão resistente, ou seja, que é pouco afetada por mudanças nas posições dos dados. Os resultados obtidos indicaram uma variabilidade de 2,42 graus entre os ângulos, 0,50 metros entre as medianas de X e 1,25 metros entre as medianas de Y. Assim, pudemos concluir que não houve grande variabilidade entre as medições do jogador analisado, e a metodologia utilizada é um meio preciso para a análise tática no futebolThe main goal of this study was to analyze the variability in the measurement of soccer players' tactical positioning. Twenty analyses were made during the first half of the game between Corinthians and Palmeiras, valid for the Libertadores of America 1999's Cup. The action places of the Corinthians team player Vampeta were registered using a software that simulates a soccer pitch and marks the places on which the players are positioned during each action. After marking all the players actions, two principal axes, which substituted the action places, were built for every game analysed. The eigenvectors are ortogonal between themselves and the intersection point between the two axes was centered in the median of X and Y. The length of the principal axes was determined by the most distant points, after selecting the percentage of the data used for its construction. In this case, the data were restricted to the ninetieth percentil. The variability was measured by the BOXPLOT interquartil interval, which is a measure for the resisting dispersion, in other words, that is little affected by changes in the data positions. The results indicated a variability of 2.42 degrees between the angles, 0.50 meters between the X median, and 1.25 meters between the Y median. We could therefore conclude that there was no great variability between the measurements of the player analysed, and the methodology used is an accurate mean for soccer tactical analysis

Utilização da ultrassonografia como método auxiliar no posicionamento de marcadores em análise de movimento de equinos

A análise cinemática do movimento é baseada na reconstrução de pontos anatômicos específicos identificados por marcadores de superfície. Esses pontos de referência geralmente não correspondem a pontos, mas a áreas relativamente grandes e curvas de difícil identificação pela palpação. A colocação precisa dos marcadores de superfície é ainda mais difícil e há grande variabilidade entre examinadores. Neste estudo 16 examinadores foram submetidos à identificação da borda lateral da tuberosidade isquiática esquerda de um cavalo usando a palpação e a ultrassonografia para colocar um marcador de superfície. Imagens de cada procedimento de marcação foram adquiridas utilizando duas câmeras de vídeo digital e processadas utilizando o sistema de videogrametria DVideow.  O software Matlab foi usado para determinar a posição dos respectivos vetores. As posições dos marcadores foram comparadas para avaliar a variabilidade entre os examinadores e a precisão do método empregado através do teste de Bartlett e teste t pareado respectivamente. A ultrassonografia melhorou significativamente a localização dos pontos anatômicos de cada examinador (p = 0,04) e reduziu a variabilidade no posicionamento dos marcadores de superfície quando comparada a palpação (p = 0,0028). A variabilidade das distâncias calculadas (média ± dp) foi de 2,89 ± 2,24 cm e 1,63 ± 0,98 cm usando a palpação e a ultrassonografia respectivamente. A ultrassonografia reduziu a variabilidade entre examinadores e permitiu a visualização do ponto anatômico correspondente.Kinematic motion analysis is based on the reconstruction of selected bony anatomical landmarks identified by surface markers. Anatomical landmarks generally do not correspond to points but rather to relatively large and curved areas and their identification by palpation is not easy. Precise placement of surface markers is even more difficult and there is great variability between operators. In this study 16 examiners were asked to identify the lateral border of the left ischial tuberosity in a horse using palpation and ultrasonography for placement of a corresponding skin surface marker. Images of each marking procedure were captured using two video cameras and processed using the DVideow videogrammetry. A custom-written Matlab code was used to determine the position of the respective vectors. The positions of the markers were then compared to assess inter-examiner variability and the precision of the methods employed using the Bartletttest and the paired t-test respectively. Ultrasonography significantly improved the location of the anatomical landmark by each examiner (p = 0.04) and reduced the variability in the position of the surface marker when compared to palpation (p = 0.0028). The variability of the calculated distances (mean ± SD) was 2.89 ± 2.24 cm and 1.63 ± 0.98 cm using palpation and ultrasonography respectively. Ultrasound guidance reduced inter-examiner variability and allowed visualization of the corresponding bony anatomical landmark

Ultrasonography as an ancillary method for the positioning of markers in equine motion analysis

Kinematic motion analysis is based on the reconstruction of selected bony anatomical landmarks identified by surface markers. Anatomical landmarks generally do not correspond to points but rather to relatively large and curved areas and their identification by palpation is not easy. Precise placement of surface markers is even more difficult and there is great variability between operators. In this study 16 examiners were asked to identify the lateral border of the left ischial tuberosity in a horse using palpation and ultrasonography for placement of a corresponding skin surface marker. Images of each marking procedure were captured using two video cameras and processed using the DVideow videogrammetry. A custom-written Matlab code was used to determine the position of the respective vectors. The positions of the markers were then compared to assess inter-examiner variability and the precision of the methods employed using the Bartletttest and the paired t-test respectively. Ultrasonography significantly improved the location of the anatomical landmark by each examiner (p = 0.04) and reduced the variability in the position of the surface marker when compared to palpation (p = 0.0028). The variability of the calculated distances (mean ± SD) was 2.89 ± 2.24 cm and 1.63 ± 0.98 cm using palpation and ultrasonography respectively. Ultrasound guidance reduced inter-examiner variability and allowed visualization of the corresponding bony anatomical landmark

System for kinemâtical analysis of the human gait based on videogra

Three-dimensional kinematic analysis has been used as an important research method for assessing normal or pathological human gait. However, due to several factors, such analysis is not widespread in Brazil. The aim of this paper is to present results of a three-dimensional kinematic analysis of the human gait by means of a Brazilian videogrammetry system - Dvideow, d e v e l o p e d by the Laboratório deInstrumentação para Biomecânica at Unicamp, SP. A complete gait cycleof three female adult subjects with no history of pathologies or gaitcomplaints was evaluated. The lower limbs and pelvis were tahcen as rigidbodies articulated by six joints, each representing a body segment. In order to obtain position and space orientation for each body segment, reflexive markers (f=15mm) were fixed onto anatomical landmarkers and in a technical markers system. The ankle, knee and hip joint angles wereanalyzed, as well as trie pelvis orientation. Results w e r e evaluateaby means of accuracy tests of the reconstruction of the path described by two markers during the gait; accuracy relative to framing was of 0,2%. Data obtained agree to those described in the literature. It is shown that it is possible to make gait analysis using the Dvideow system, which allows for analysing the ankle joint with three degrees of freedom and for simultaneous visual and quantitative analysis.A análise cinemática tridimensional vem sendo utilizada como importante método de pesquisa e avaliação da marcha humana, normal ou patológica. No entanto, ainda é pouco difundida no Brasil, devido a uma série de fatores. Este artigo apresenta resultados de análise cinemáticatridimensional da marcha humana realizada c om base no sistema brasileiro de videogrametria Dvideow, desenvolvido pelo Laboratório deInstrumentação para Biomecânica da UNICAMP. Foi analisada a marcha de três voluntárias adultas, sem histórico de patologias ou comprometimento do andar. Os membros inferiores e a pelve foram tratados como corpos rígidos unidos por seis articulações, cada qual representando um segmento corporal. Para obter posição e orientação de cada segmento no espaço, marcadores retrorrefletivos (f=15mm) foram fixados em pontosanatômicos das voluntárias e em sistemas de marcas técnicas. Nas imagens de um ciclo de marcha, foram analisados os ângulos articulares do tornozelo, joelho e quadril, além da orientação da pelve. Os dados coletados foram avaliados por testes de acurácia da reconstrução da trajetória de dois marcadores durante a marcha; a acurácia relativa ao enquadramento utilizado foi de 0,2%. Os resultados encontrados concordam com os descritos na literatura. Conclui-se que é possível realizar análise da marcha humana pelo sistema Dvideow, com a possibilidade de analisar a articulação do tornozelo com três graus de liberdade e com integração da análise visual à quantitativa

ANALYSIS OF THE SHOTS TO GOAL STRATEGIES OF FIRST DIVISION BRAZILIAN PROFESSIONAL SOCCER TEAMS

The purpose of this study was to analyze the shots to goal strategies during four soccer matches, through computational tracking. Software Dvideow was used to obtain data about players’ position and their technical actions and data treatment was performed in Matlab® environment. The results showed that the teams usually win the ball possession in their defensive soccer field and ball possessions that resulted in shot to goal can involve few or great number of passes depending on the game situation. Results do not corroborate with literature studies due to different methods of data treatment. Information about to these shots to goal strategies can help coaches to improve technical training, to find possible team mistakes and present it to players

3D KINEMATICAL ANALYSIS OF THE HAMMER THROW IN COMPETITIONS

This study analyzes 14 throws accomplished in Brazilian competitions and it compares with available international results in the literature. It calculates the angle, the velocity and the height of release of the hammer and the velocity curves in function of the time, starting from the 3D trajectory of the head of the hammer. The analyses relate the difference between Brazilian (averages of 55.38m male and 52.05m female) and international results (averages of 79.44m male and 70.60m female) and the release velocity (Brazilian averages of 24.59m/s male and 23.59m/s female, and international of 29.60m/s male and 28.89m/s female). The velocity curves in function of the time of the international releases show that the accelerations are higher and the deceleration lower during the turns, when compared with a Brazilian throw