Effect of arm motion on standing lateral jumps

2019 ◽  
Vol 96 ◽  
pp. 109339
Author(s):  
Blake M. Ashby ◽  
Arif Ahmed Sohel ◽  
Gordon J. Alderink
Keyword(s):  
2005 ◽  
Author(s):  
Frédéric Meyer ◽  
Fabio Borrani ◽  
Rose-Marie Repond

Author(s):  
Pier Giorgio Golzio ◽  
Arianna Bissolino ◽  
Raffaele Ceci ◽  
Simone Frea

Abstract Background ‘Idiopathic’ lead macrodislodgement may be due to Twiddler’s syndrome depending on active twisting of pulse generator within subcutaneous pocket. All leads are involved, at any time from implantation, and frequently damaged. In the past few years, a reel syndrome was also observed: retraction of pacemaker leads into pocket without patient manipulation, owing to lead circling the generator. In other cases, a ‘ratchet’ mechanism has been postulated. Reel and ratchet mechanisms require loose anchoring, occur generally briefly after implantation, with non-damaged leads. We report the first case of an active-fixation coronary sinus lead selective macrodislodgement involving such ratchet mechanism. Case summary A 65-year-old man underwent biventricular defibrillator device implantation, with active-fixation coronary sinus lead. Eight months later, he complained of muscle contractions over device pocket. At fluoroscopy, coronary sinus lead was found near to pocket, outside of thoracic inlet. Atrial and ventricular leads were in normal position. After opening pocket, a short tract of coronary sinus lead appeared anteriorly dislocated to generator, while greater length of lead body twisted a reel behind. The distal part of lead was found outside venous entry at careful dissection. Atrial and ventricular leads were firmly anchored. Discussion Our case is a selective ‘Idiopathic’ lead macrodislodgement, possibly due to a ratchet mechanism between the lead and the suture sleeve, induced by normal arm motion; such mechanism incredibly, and for first time in literature involves a coronary sinus active-fixation lead. Conclusion Careful attention should always be paid to secure anchoring even of active-fixation coronary sinus leads.


2012 ◽  
Vol 516 ◽  
pp. 234-239 ◽  
Author(s):  
Wei Wu ◽  
Toshiki Hirogaki ◽  
Eiichi Aoyama

Recently, new needs have emerged to control not only linear motion but also rotational motion in high-accuracy manufacturing fields. Many five-axis-controlled machining centres are therefore in use. However, one problem has been the difficulty of creating flexible manufacturing systems with methods based on the use of these machine tools. On the other hand, the industrial dual-arm robot has gained attention as a new way to achieve accurate linear and rotational motion in an attempt to control a working plate like a machine tool table. In the present report, a cooperating dual-arm motion is demonstrated to make it feasible to perform stable operation control, such as controlling the working plate to keep a ball rolling around a circular path on it. As a result, we investigated the influence of each axis motion error on a ball-rolling path.


2003 ◽  
Vol 15 (05) ◽  
pp. 186-192 ◽  
Author(s):  
WEN-LAN WU ◽  
JIA-HROUNG WU ◽  
HWAI-TING LIN ◽  
GWO-JAW WANG

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.


2009 ◽  
Vol 2 (2) ◽  
pp. 61-69 ◽  
Author(s):  
Yukyung Choi ◽  
SyungKwon Ra ◽  
Soowhan Kim ◽  
Sung-Kee Park

2005 ◽  
Vol 02 (01) ◽  
pp. 105-124 ◽  
Author(s):  
VELJKO POTKONJAK

Handwriting has always been considered an important human task, and accordingly it has attracted the attention of researchers working in biomechanics, physiology, and related fields. There exist a number of studies on this area. This paper considers the human–machine analogy and relates robots with handwriting. The work is two-fold: it improves the knowledge in biomechanics of handwriting, and introduces some new concepts in robot control. The idea is to find the biomechanical principles humans apply when resolving kinematic redundancy, express the principles by means of appropriate mathematical models, and then implement them in robots. This is a step forward in the generation of human-like motion of robots. Two approaches to redundancy resolution are described: (i) "Distributed Positioning" (DP) which is based on a model to represent arm motion in the absence of fatigue, and (ii) the "Robot Fatigue" approach, where robot movements similar to the movements of a human arm under muscle fatigue are generated. Both approaches are applied to a redundant anthropomorphic robot arm performing handwriting. The simulation study includes the issues of legibility and inclination of handwriting. The results demonstrate the suitability and effectiveness of both approaches.


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