Kinematic Analysis on the Clean and Jerk Action of the Chinese Elite Athlete Zhong Huang

We made a 3D camera resolution on the elite Chinese weightlifting athlete Zhong Huang, with the three-dimensional analysis we gained the kinematic parameters and found the problem of his technique, thus provide some scientific basis for the weight-lift training. The results show that in the barbell lifting stage, the distance of Zhong Huang’s hand is 69.6cm, a narrow grip and the depth of pre squatting is small. In the force stage, the angle of knee joint is relatively large, full squatting distance prolonging the working distance. In the squat support stage Zhong Huang had a good flexion of the hip and knee, in line with the "straight, stable, shallow" pre squatting requirements. In the stand up stage, Zhong Huang lifted the barbell and stood fast, which explains he had a good effect of force. In the jerk stage, he had an over bent of knee.

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Kinematics Analysis on the Throwing Skills of Elite Chinese Male Hammer Athletes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.950.91 ◽

2014 ◽

Vol 950 ◽

pp. 91-92

Author(s):

Shuai Wang ◽

Ji He Zhou ◽

Chong Jia

Keyword(s):

Three Dimensional ◽

Track And Field ◽

Kinematics Analysis ◽

Short History ◽

Kinematic Parameters ◽

World Record ◽

3D Camera ◽

Internal Relations ◽

Double Supporting ◽

Chinese Male

Hammer throw is one of the traditional track and field events but it only has a short history in China. Chinese hammer athlete Shizhu Wang won the championship of China Long Throw Open in 2013, but the performance in the game has a big gap with the world record. In order to improve the techniques of Chinese men hammer athletes, have a clearly understanding of the rational factors and internal relations of hammer throw technique, enrich the theory of the action and provide reference to the hammer throw training, we made a 3D camera resolution on the top three men hammer throwers (Shizhu Wang, Dakai Qi and Xiwan Jiang) at the game site of China Long Throw Open in 2013, with the three-dimensional analysis we gained the kinematic parameters. We made a comparison on the parameters between Chinese and foreign elite men hammer throwers. The result shows that: Compared with the datas of outstanding foreign athletes, the pre-swing time is much larger and hammer velocity increment is much smaller in the pre-swing stage; the total rotation time is much longer, and the single to double supporting time is distributed unreasonly, what’s more, the change between the knee joint and bevel angle are too small; the shot speed ,with the fastest Shizhu Wang of 24.87 m/s, is much slower than that of foreign famous athlete Sedych (30.7 m /s), and longer hammer throw running time, which are the main reasons that affect athletes’ performance.

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Modelling and Kinematic Analysis of a Built Up Linear Delta Robot

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.186.234 ◽

2012 ◽

Vol 186 ◽

pp. 234-238

Author(s):

Erol Uyar ◽

Lutfi Mutlu

Keyword(s):

Simulation Model ◽

Kinematic Analysis ◽

Position Control ◽

Mechanical Design ◽

Dimensional Space ◽

Three Dimensional ◽

Inverse Kinematic ◽

Kinematic Parameters ◽

Dc Motors ◽

Three Dimensional Space

In this paper kinematic analysis of a 3-PUU translational parallel manipulator (TPM) is made by creating the forward and inverse Kinematic solutions. For a given position, control of the end effecter is then realized by using the calculated inverse kinematic parameters as reference values. For kinematic analysis relevant equations are derived from geometrical vector relations. For the forward and inverse kinematic solutions of the non-linear model a MATLAB based iterative algorithm is developed and the inverse kinematic solutions of limbs, are then used to control the end effecter position through screw rails which are driven by DC motors. After the general mechanical design of the manipulator all parts are drawn and modelled in SolidWorks, and a simulation of the motion in three dimensional space is made. To support the reliability of calculated parameters through inverse kinematic solutions, results are compared with the values of SolidWorks based simulation model of the manipulator. Furthermore a real position control with use of feed back encoders is applied and the evaluated results are compared with the results of a simulation model. Very similar and satisfactory results are obtained with both simulation and real application.

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Low-light-level three-dimensional video microscope with long working distance objective lenses

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100168864 ◽

1994 ◽

Vol 52 ◽

pp. 226-227

Author(s):

W. Lin ◽

J. Gregorio ◽

T.J. Holmes ◽

D. H. Szarowski ◽

J.N. Turner

Keyword(s):

Three Dimensional ◽

Light Level ◽

Stereo Pair ◽

Light Illumination ◽

Initial Image ◽

Low Light ◽

Image Recording ◽

Depth Discrimination ◽

Video Microscope ◽

Working Distance

A low-light level video microscope with long working distance objective lenses has been built as part of our integrated three-dimensional (3-D) light microscopy workstation (Fig. 1). It allows the observation of living specimens under sufficiently low light illumination that no significant photobleaching or alternation of specimen physiology is produced. The improved image quality, depth discrimination and 3-D reconstruction provides a versatile intermediate resolution system that replaces the commonly used dissection microscope for initial image recording and positioning of microelectrodes for neurobiology. A 3-D image is displayed on-line to guide the execution of complex experiments. An image composed of 40 optical sections requires 7 minutes to process and display a stereo pair.The low-light level video microscope utilizes long working distance objective lenses from Mitutoyo (10X, 0.28NA, 37 mm working distance; 20X, 0.42NA, 20 mm working distance; 50X, 0.42NA, 20 mm working distance). They provide enough working distance to allow the placement of microelectrodes in the specimen.

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BIOMECHANICAL ANALYSIS OF THE STANDING LONG JUMP

Biomedical Engineering Applications Basis and Communications ◽

10.4015/s1016237203000286 ◽

2003 ◽

Vol 15 (05) ◽

pp. 186-192 ◽

Cited By ~ 12

Author(s):

WEN-LAN WU ◽

JIA-HROUNG WU ◽

HWAI-TING LIN ◽

GWO-JAW WANG

Keyword(s):

Knee Joint ◽

Motion Analysis ◽

Joint Angle ◽

Three Dimensional ◽

The Body ◽

Initial Angle ◽

Knee Joint Angle ◽

Standing Long Jump ◽

Long Jump ◽

Arm Motion

The purposes of the present study were to (1) investigate the effects of the arm movement and initial knee joint angle employed in standing long jump by the ground reaction force analysis and three-dimensional motion analysis; and (2) investigate how the jump performance of the female gender related to the body configuration. Thirty-four healthy adult females performed standing long jump on a force platform with full effort. Body segment and joint angles were analyzed by three-dimensional motion analysis system. Using kinetic and kinematic data, the trajectories on mass center of body, knee joint angle, magnitude of peak takeoff force, and impulse generation in preparing phase were calculated. Average standing long jump performances with free arm motion were +1.5 times above performance with restricted arm motion in both knee initial angles. The performances with knee 90° initial flexion were +1.2 times above performance with knee 45° initial flexion in free and restricted arm motions. Judging by trajectories of the center mass of body (COM), free arm motion improves jump distance by anterior displacement of the COM in starting position. The takeoff velocity with 90° knee initial angle was as much as 11% higher than in with 45° knee initial angle. However, the takeoff angles on the COM trajectory showed no significant differences between each other. It was found that starting jump from 90° bend knee relatively extended the time that the force is applied by the leg muscles. To compare the body configurations and the jumping scores, there were no significant correlations between jump scores and anthropometry data. The greater muscle mass or longer leg did not correlated well with the superior jumping performance.

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Simulation Analysis of Pneumatic on-off Pressure Mechanism on Printing Press

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.154-155.1481 ◽

2010 ◽

Vol 154-155 ◽

pp. 1481-1484 ◽

Cited By ~ 1

Author(s):

Jun Zhong Guo ◽

Jun Ping Yang

Keyword(s):

Kinematic Analysis ◽

Simulation Analysis ◽

Angular Displacement ◽

Three Dimensional ◽

Printing Press ◽

Work Demand ◽

Analysis Process ◽

Adams Software ◽

Important Basis

The on-off pressure mechanism has an important function to the printing press, the quality of which concerns the working performance of the printing machine and the quality of printed products directly. In this paper, the pneumatic on-off pressure mechanism is discussed; the work demand of order on-off pressure is analyzed. In addition, the three-dimensional digital model and the kinematic analysis process can be achieved on the basis of ADAMS software. What’s more, the on pressure value in the process of on pressure is derived from the kinematic analysis. Lastly, the relation between the motion of on-off pressure mechanism and cylinder’s angular displacement is analyzed, an important basis to the on-off pressure mechanism’s optimal design will be provided.

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Three-dimensional kinematic analysis of influence of hand orientation and joint limits on the control of arm postures and movements

Biological Cybernetics ◽

10.1007/s004220050538 ◽

1999 ◽

Vol 80 (6) ◽

pp. 449-463 ◽

Cited By ~ 45

Author(s):

Xuguang Wang

Keyword(s):

Kinematic Analysis ◽

Three Dimensional ◽

Hand Orientation ◽

Joint Limits

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In Vivo Tracking of the Human Patella Using Cine Phase Contrast Magnetic Resonance Imaging

Journal of Biomechanical Engineering ◽

10.1115/1.2800868 ◽

1999 ◽

Vol 121 (6) ◽

pp. 650-656 ◽

Cited By ~ 86

Author(s):

F. T. Sheehan ◽

F. E. Zajac ◽

J. E. Drace

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Knee Joint ◽

Phase Contrast ◽

Three Dimensional ◽

Resonance Imaging ◽

Contrast Magnetic Resonance ◽

Knee Joint Kinematics ◽

Cine Phase Contrast

Improper patellar tracking is often considered to be the cause of patellar-femoral pain. Unfortunately, our knowledge of patellar-femoral-tibial (knee) joint kinematics is severely limited due to a lack of three-dimensional, noninvasive, in vivo measurement techniques. This study presents the first large-scale, dynamic, three-dimensional, noninvasive, in vivo study of nonimpaired knee joint kinematics during volitional leg extensions. Cine-phase contrast magnetic resonance imaging was used to measure the velocity profiles of the patella, femur, and tibia in 18 unimpaired knees during leg extensions, resisted by a 34 N weight. Bone displacements were calculated through integration and then converted into three-dimensional orientation angles. We found that the patella displaced laterally, superiorly, and anteriorly as the knee extended. Further, patellar flexion lagged knee flexion, patellar tilt was variable, and patellar rotation was fairly constant throughout extension.

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INTRA-SESSION RELIABILITY AND REPEATABILITY OF KNEE KINEMATICS IN SUBJECTS WITH ACL DEFICIENCY DURING STAIR ASCENT

Journal of Mechanics in Medicine and Biology ◽

10.1142/s0219519417500920 ◽

2017 ◽

Vol 17 (06) ◽

pp. 1750092

Author(s):

MARYAM HAJIZADEH ◽

ALIREZA HASHEMI OSKOUEI ◽

FARZAN GHALICHI ◽

GISELA SOLE

Keyword(s):

Knee Joint ◽

Cruciate Ligament ◽

Intraclass Correlation ◽

Force Plate ◽

Three Dimensional ◽

Knee Kinematics ◽

Compensatory Mechanisms ◽

Joint Rotation ◽

Stair Ascent ◽

Acl Deficient

Analysis of knee kinematics and ground reaction forces (GRFs) is widely used to determine compensatory mechanisms of people with anterior cruciate ligament deficiency (ACLD). However, the practicality of the measurements is subject to their reliability during different trials. This study aims to determine the reliability and repeatability of knee joint rotations and GRFs in people with ACLD during stair ascent. Eight participants with unilateral ACL-deficient knees performed five trials of stair ascent with each leg. The movements were captured by VICON motion analysis system, and GRF components were recorded using force plate. Three-dimensional tibiofemoral joint rotations were calculated. Intraclass correlation coefficient (ICC), standard error of measurement (SEM) and coefficient of multiple correlation (CMC) were calculated ACL-deficient legs showed lower absolute reliability during swing ([Formula: see text]–6.4) than stance phase ([Formula: see text]–2.2) for knee joint rotations. Moderate to high average measure ICCs (0.59–0.98), relative reliability, were achieved for injured and uninjured sides. The results also demonstrated high repeatability for the knee joint rotation ([Formula: see text]–0.97) and GRF ([Formula: see text]–0.99). The outcomes of this study confirmed the consistency and repeatability of the knee joint rotations and GRFs in ACL-deficient subjects. Additionally, ACL-deficient legs exhibited similar levels of reliability and repeatability compared to contralateral legs.

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