scholarly journals Three-Dimensional Upper Body Kinematics and Inter-articular Kinematic Sequence During a Canoe Polo Throw

2021 ◽  
Vol 3 ◽  
Author(s):  
Najoua Assila ◽  
Cyril Delavallade ◽  
Yoann Blache ◽  
Christian Berger-Vachon ◽  
Philippe Collotte ◽  
...  
Keyword(s):  
Angular Velocity ◽  
Inverse Kinematics ◽  
Three Dimensional ◽  
Statistical Parametric Mapping ◽  
Vertical Axis ◽  
Axial Rotation ◽  
Upper Body ◽  
Parametric Mapping ◽  
Overhead Sports ◽  
Angular Velocities

Canoe polo is an increasingly popular discipline requiring both kayaking and ball-handling skills. While the kinematics of the upper body during throw has been investigated for several overhead sports, the canoe polo throw has still to be studied. Therefore, the aim of this study is to analyze the canoe polo throw kinematics in terms of angles and inter-articular sequencing to understand its specificity. A secondary aim was to investigate whether adding pelvis mobility has an impact. Nineteen male players of canoe polo were equipped with reflective body markers for the throw analysis. They performed 5 throws with the pelvis fixed and 5 throws with additional pelvic mobility in rotation around a vertical axis. Inverse kinematics was performed with OpenSim providing pelvis, trunk, and glenohumeral rotations. Angular velocities were calculated to build the inter-articular sequences relative to these throws. Statistical parametric mapping was used to assess the effect of pelvis mobility on the throwing kinematics. Similar kinematics patterns as in other overhead sports were observed, however, a different inter-articular sequence was found for the canoe polo throw with a maximal angular velocity occurring sooner for the thorax in axial rotation than for the pelvis in rotation. While the limitation of rotation of the pelvis around a vertical axis has an influence on the pelvis and trunk kinematics, it did not modify the kinematic sequence.

scholarly journals The Effect of Golf Club Moment of Inertia on Clubhead Delivery and Golfer Kinematics

Proceedings ◽  
2020 ◽  
Vol 49 (1) ◽  
pp. 96
Author(s):  
Josh Turner ◽  
Stephanie E. Forrester ◽  
Aimée C. Mears ◽  
Jonathan R. Roberts
Keyword(s):  
Statistical Parametric Mapping ◽  
Axial Rotation ◽  
Moment Of Inertia ◽  
Golf Club ◽  
Wrist Flexion ◽  
Contributing Factors ◽  
Parametric Mapping ◽  
Paired Sample

The purpose of this study was to determine the effect of modifying whole club moment of inertia (MOI) on clubhead delivery, thorax and wrist kinematics. Seven skilled golfers hit ~10 shots with two driver conditions (MOI difference ~400 kg∙cm2). A GOM system tracked the clubhead at impact and a 12-camera Vicon system was used to determine golfer biomechanics. Paired sample t-tests were conducted to quantify the effect of MOI on clubhead delivery, whilst biomechanical differences during the downswing were determined using statistical parametric mapping. Increasing MOI significantly reduced clubhead velocity (p = 0.001) but had a small and non-significant effect (p ≥ 0.294) on clubhead direction and orientation. The increase in MOI significantly decreased lead wrist flexion, thorax lateral bend and thorax axial rotation velocities during the downswing. The timing and magnitude of the decreases in both thorax velocities, suggests that these were contributing factors of the observed decrease in clubhead velocity.

scholarly journals Head and body dyskinesia during gait in tactical athletes with vestibular deficit following concussion

2021 ◽  
Author(s):  
John J Fraser ◽  
Jacob A VanDehy ◽  
Dawn M Bodell ◽  
Kim R Gottshall ◽  
Pinata H Sessoms
Keyword(s):  
Walking Speed ◽  
Center Of Mass ◽  
Three Dimensional ◽  
Statistical Parametric Mapping ◽  
Neurological Impairment ◽  
Control Group ◽  
Initial Contact ◽  
Parametric Mapping ◽  
Movement Strategy ◽  
Vestibular Deficit

Background: Vestibular deficit is common following concussion and may affect gait. The purpose of this study was to investigate differences in head and pelvic center of mass (COM) movement during gait in tactical athletes with and without concussion-related central vestibular impairment. Methods: 24 patients with post-concussion vestibular impairment (20 males, 4 females; age: 31.7±7.9 years; BMI: 27.3±3.3) and 25 matched controls (21 males, 4 females; age: 31.8±6.4 years; BMI: 27.2±2.6) were included. Three-dimensional head and pelvic COM displacement and velocities were collected at a 1.0 m/s standardized treadmill walking speed and assessed using Statistical Parametric Mapping t-tests. Maximum differences (dmax) between groups were reported for all significant kinematic findings. Results: The Vestibular group demonstrated significantly diminished anteroposterior head excursions (dmax=2.3 cm, p=0.02;) and slower anteroposterior (dmax=0.37 m/s, p=0.01), mediolateral (dmax=0.47 m/s, p=0.02) and vertical (dmax=0.26 m/s, p<0.001) velocities during terminal stance into pre-swing phases compared to the Control group. Vertical pelvic COM excursion was significantly increased in midstance (dmax=2.4 cm, p=0.03) and mediolaterally during pre- to initial-swing phases (dmax=7.5 cm, p<0.001) in the Vestibular group. In addition, Pelvic COM velocities of the Vestibular group were higher mediolaterally during midstance (dmax=0.19 m/s, p=0.02) and vertically during post-initial contact (dmax=0.14 m/s, p<0.001) and pre-swing (dmax=0.16 m/s, p<0.001) compared to the Control group. Significance: The Vestibular group demonstrated a more constrained head movement strategy during gait compared with Controls, a finding that is likely attributed to a neurological impairment of visual-vestibular-somatosensory integration.

Three-dimensional kinematic analysis of upper limb movements between individuals with and without subacromial shoulder pain exploring the statistical parametric mapping

2021 ◽  
pp. 110806
Author(s):  
Diogo Henrique Magalhães Gonçalves ◽  
Anamaria Siriani de Oliveira ◽  
Lucas Cruz Freire ◽  
Ana Beatriz Marcelo Silva ◽  
Silvio Antonio Garbelotti ◽  
...  
Keyword(s):  
Shoulder Pain ◽  
Upper Limb ◽  
Kinematic Analysis ◽  
Three Dimensional ◽  
Statistical Parametric Mapping ◽  
Limb Movements ◽  
Parametric Mapping ◽  
Upper Limb Movements

scholarly journals Statistical parametric mapping of three-dimensional local activity distribution of skeletal muscle using magnetic resonance imaging (MRI)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Satoshi Yamaguchi ◽  
Makoto Watanabe ◽  
Yoshinori Hattori
Keyword(s):  
Magnetic Resonance Imaging ◽  
Skeletal Muscle ◽  
Magnetic Resonance ◽  
Muscle Activity ◽  
Three Dimensional ◽  
Statistical Parametric Mapping ◽  
Resonance Imaging ◽  
Parametric Mapping ◽  
Local Activity ◽  
Activity Distribution

AbstractAnalysis of the internal local activity distribution in human skeletal muscles is important for managing muscle fatigue/pain and dysfunction. However, no method is established for three-dimensional (3D) statistical analysis of features of activity regions common to multiple subjects during voluntary motor tasks. We investigated the characteristics of muscle activity distribution from the data of ten healthy subjects (29 ± 1 year old, 2 women) during voluntary teeth clenching under two different occlusal conditions by applying spatial normalization and statistical parametric mapping (SPM) to analysis of muscle functional magnetic resonance imaging (mfMRI) using increase in transverse relaxation time (T2) of the skeletal muscle induced by exercise. The expansion of areas with significant T2 increase was observed in the masticatory muscles after clenching with molar loss comparing with intact dentition. The muscle activity distribution characteristics common to a group of subjects, i.e., the active region in the temporal muscle ipsilateral to the side with the molar loss and medial pterygoid muscle contralateral to the side with the molar loss, were clarified in 3D by applying spatial normalization and SPM to mfMRI analysis. This method might elucidate the functional distribution within the muscles and the localized muscular activity related to skeletal muscle disorders.

3-D Analysis of the Flight Trajectories of Flies (Drosophila melanogaster)

1980 ◽  
Vol 35 (9-10) ◽  
pp. 811-815 ◽  
Author(s):  
Heinrich Buelthoff ◽  
Tomaso Poggio ◽  
Christian Wehrhahn
Keyword(s):  
Drosophila Melanogaster ◽  
Angular Velocity ◽  
Computer System ◽  
Three Dimensional ◽  
Strongly Correlated ◽  
Free Flight ◽  
Flight Behaviour ◽  
Error Angle ◽  
Angular Velocities ◽  
Flight Trajectories

Abstract We have developed a computer system for reconstructing and analyzing three dimensional flight trajectories of flies. Its application to the study of the free flight behaviour of the fruitfly Drosophila melanogaster is described. The main results are: a) Drosophila males only occasionally track other flies; b) in such cases the fly’s angular velocity is a function of the error angle under which the leading fly is seen; c) body saccades can be demonstrated during cruising flights; d) high angular velocities are strongly correlated with low forward velocities, probably reflecting an aerodynamic constraint of flight. The 3-D technique described may provide an adequate tool for studying the organization of the systems present in flies and for relating the free flight behaviour to previous analyses of tethered flies.

scholarly journals Axial rotation as a cause of loss of interference in a shrink fitted split disc assembly

2021 ◽  
pp. 19-32
Author(s):  
Анатолий Александрович Буренин ◽  
Анастасия Валерьевна Ткачева
Keyword(s):  
Angular Velocity ◽  
Axial Rotation ◽  
Thermomechanical Properties ◽  
Operating Conditions ◽  
Relative Rotation ◽  
Centrifugal Forces ◽  
Interference Fit ◽  
Final Structure ◽  
Angular Velocities ◽  
Composite Disk

На примере составного диска, созданного посредством операции горячей посадки, изучается прочность такого соединения на отрыв. Отрывные усилия создаются в качестве центробежных инерционных сил при вращении диска относительное его центральной оси. Показывается, что созданный натяг в сборке имеет выраженную тенденцию к уменьшению. Однако для его обнуления необходимы достаточно значительные угловые скорости вращения. Приведен пример расчета придельной угловой скорости в зависимости от первоначального нагрева охватывающей детали сборки, термомеханических свойств материала сборки и геометрических параметров итоговой конструкции. Подобные расчеты в снижающемся натяге совершенно необходимы, когда эксплуатационные условия требуют принять вращение составного диска в качестве части его функциональных обязанностей. On the example of a composite disk, created by means of a hot-fit operation, the pulloff strength of such a disk is studied. separation forces as centrifugal forces with relative rotation of its central axis. It is shown that the created interference fit in the assembly has a pronounced tendency to decrease. However, for vanishing, sufficiently significant angular velocities of rotation are required. An example of calculating the near-limit angular velocity, depending on the original covered part of the assembly, of the thermomechanical properties of the material and the geometric characteristics of the final structure is given. Such computations in decreasing interference are essential when operating conditions require the rotation of the composite disc to be accepted as part of its functionality.

scholarly journals Method for Predicting the Liquid-Sloshing Characteristics of a Microsatellite Propulsion System

2019 ◽  
Vol 2019 ◽  
pp. 1-17 ◽  
Author(s):  
L. Teng ◽  
T. Meng ◽  
Zh. H. Jin
Keyword(s):  
Angular Velocity ◽  
Storage Tank ◽  
Three Dimensional ◽  
Propulsion System ◽  
Liquid Sloshing ◽  
Particle Hydrodynamics ◽  
Calculation Results ◽  
Angular Velocities ◽  
Three Dimensional Coordinate ◽  
Minimum Disturbance

In this study, a method for establishing a prediction model for the liquid-sloshing characteristics of microsatellite propulsion systems is proposed. The ideal states of the liquid-sloshing characteristics are considered for the following three models: (1) storage tank, (2) coupled storage tank and microsatellite, and (3) coupled storage tank and microsatellite with a deployment mechanism. The smoothed-particle hydrodynamics method is implemented in ABAQUS to study the effect of sloshing on a storage tank and microsatellite disturbance for the above three cases. Relationship models between the sloshing time, sloshing angular velocity, amount of fluid filled, and satellite attitude angular velocity are established. The analysis results show that the disturbance angular velocity of the empty storage tank and sloshing angular velocity have a linear relationship. Furthermore, the disturbance angular velocity of the liquid-filled storage tank exhibits a surface relationship with the sloshing angular velocity and amount of fluid filled in a three-dimensional coordinate system. Additionally, the disturbance angular velocity in the liquid-filled state of the storage tank is higher than that of the empty storage tank, and the degree of disturbance decreases with the increase in the mass of the coupling. The disturbance of the storage tank and microsatellite with the deployment mechanism is 10−2°/s when the angular velocities of the satellite are ωx′=3, ωy′=3, and ωz′=2. The maximum and minimum deviations between the calculation and simulation results of the three models are 7.6% and 1.1%, respectively. The model is used to predict the disturbance angular velocity of the microsatellite. When the calculation results of the model are compared with the orbit satellite data, the maximum and minimum disturbance angular velocity deviations occur in the y and z directions with a deviation of 43.36% and 14.86%, respectively. This demonstrates the accuracy of the analysis and model. The results of this study can provide theoretical guidance for the engineering design and attitude and orbital control of a microsatellite propulsion system.

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