Analisis Perubahan Momentum Tubuh Bagian Atas Pada Saat Pukulan Tennis One-Handed Backhand Drive

Agus Rusdiana

doi:10.26877/jo.v6i2.8040

Analisis Perubahan Momentum Tubuh Bagian Atas Pada Saat Pukulan Tennis One-Handed Backhand Drive

Jendela Olahraga ◽

10.26877/jo.v6i2.8040 ◽

2021 ◽

Vol 6 (2) ◽

pp. 29-39

Author(s):

Agus Rusdiana

Keyword(s):

Angular Momentum ◽

Vertical Direction ◽

Linear Momentum

Tujuan dari penelitian ini adalah menganalisis perpindahan linear dan angular momentum dari gerak tubuh bagian atas (upper extrimity) sampai perkenaan bola dengan raket pada saat melakukan pukulan backhand drive dengan satu tangan pada permainan tenis. Pukulan backhand drive adalah salah satu teknik yang paling sering digunakan dalam bermain tenis. Sangat sedikit penelitian yang menganalisis kajian terkait transfer linear momentum dan momentum rotasi dari gerak upper extrimity sampai perkenaan bola dengan raket pada saat melakukan pukulan backhand drive dengan satu tangan. Subjek dalam penelitian ini adalah pemain tenis putra yang berjumlah 12 orang (rata-rata ± SD; usia 27 ± 3.7 tahun, tinggi batang tubuh 169 ± 7.4 cm, berat batang tubuh 71.5 ± 8.3 kg). Metode yang digunakan adalah deskriptif dengan pendekatan kualitatif. Hasil penelitian ini menunjukan bahwa segmen tangan berkontribusi signifikan terhadap perubahan linear momentum (leading dan vertical direction) dan angular momentum (supination). Kesimpulan hasil penelitian ini adalah bahwa pemahaman tentang perubahan gerak kinetika, momentum dan force sangat penting dipahami pemain dan pelatih dalam upaya meningkatkan performa kualitas pukulan backhand drive dalam permainan tenis.

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MOMENTUM TRANSFER OF UPPER EXTREMITY IN TENNIS ONE-HANDED BACKHAND DRIVE

Journal of Mechanics in Medicine and Biology ◽

10.1142/s0219519405001436 ◽

2005 ◽

Vol 05 (02) ◽

pp. 231-241 ◽

Cited By ~ 2

Author(s):

LIN-HWA WANG ◽

HWAI-TING LIN

Keyword(s):

Angular Momentum ◽

Upper Extremity ◽

Vertical Direction ◽

Linear Momentum ◽

Point Of View ◽

Anatomic Landmarks ◽

Obvious Effect ◽

Tennis Players ◽

Injury Mechanisms ◽

Kinetics Of

Study Design: Linear momentum and angular momentum in trunk and upper extremity segments in one-handed backhand drive were calculated. Objective: To investigate the characteristics and transfer of linear momentum and angular momentum from the trunk and upper extremity to racket during tennis one-handed backhand drive. Background: Backhand stroke is one of the most frequently used techniques in playing tennis. Very few studies have taken the point of view from the transfer linear and angular momentum of the trunk and upper extremity to racket during tennis one-handed backhand drive. Methods: Six right-handed elite male tennis players participated in this study. Mean age was 26 ± 2.71 years. Sixteen markers were attached on the selected anatomic landmarks unilaterally and three markers attached on the racket to define the coordinate system of the trunk, upper arm, forearm, hand, and racket. Results: Hand contributed the most force for the changes of both linear momentum (leading and vertical direction) and angular momentum (supination). Racket and hand had similar curves in the three directions, which shows the main control racket is from hand and obvious effect in one-handed backhand stroke performance. Conclusions: An understanding of kinetics of the backhand stroke is essential for understanding injury mechanisms and prevention.

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Application of an Angular Momentum Balance Method for Investigating Numerical Accuracy in Swirling Flow

Journal of Fluids Engineering ◽

10.1115/1.1595673 ◽

2003 ◽

Vol 125 (4) ◽

pp. 723-730

Author(s):

H. Nilsson ◽

L. Davidson

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Angular Momentum ◽

Swirling Flow ◽

Linear Momentum ◽

Correct Solution ◽

Momentum Balance ◽

Numerical Accuracy ◽

Water Turbine ◽

Water Turbines

This work derives and applies a method for the investigation of numerical accuracy in computational fluid dynamics. The method is used to investigate discretization errors in computations of swirling flow in water turbines. The work focuses on the conservation of a subset of the angular momentum equations that is particularly important to swirling flow in water turbines. The method is based on the fact that the discretized angular momentum equations are not necessarily conserved when the discretized linear momentum equations are solved. However, the method can be used to investigate the effect of discretization on any equation that should be conserved in the correct solution, and the application is not limited to water turbines. Computations made for two Kaplan water turbine runners and a simplified geometry of one of the Kaplan runner ducts are investigated to highlight the general and simple applicability of the method.

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Inertia parameter identification of anunknown captured space target

Aircraft Engineering and Aerospace Technology ◽

10.1108/aeat-04-2018-0128 ◽

2019 ◽

Vol 91 (8) ◽

pp. 1147-1155 ◽

Cited By ~ 1

Author(s):

Xiaofeng Liu ◽

Bangzhao Zhou ◽

Boyang Xiao ◽

Guoping Cai

Keyword(s):

Angular Momentum ◽

Parameter Identification ◽

Linear Momentum ◽

Content Type ◽

Identification Method ◽

Robot Arms ◽

Precise Estimation ◽

Inertia Parameter ◽

Inertia Parameters ◽

Space Target

Purpose The purpose of this paper is to present a method to obtain the inertia parameter of a captured unknown space target. Design/methodology/approach An inertia parameter identification method is proposed in the post-capture scenario in this paper. This method is to resolve parameter identification with two steps: coarse estimation and precise estimation. In the coarse estimation step, all the robot arms are fixed and inertia tensor of the combined system is first calculated by the angular momentum conservation equation of the system. Then, inertia parameters of the unknown target are estimated using the least square method. Second, in the precise estimation step, the robot arms are controlled to move and then inertia parameters are once again estimated by optimization method. In the process of optimization, the coarse estimation results are used as an initial value. Findings Numerical simulation results prove that the method presented in this paper is effective for identifying the inertia parameter of a captured unknown target. Practical implications The presented method can also be applied to identify the inertia parameter of space robot. Originality/value In the classic momentum-based identification method, the linear momentum and angular momentum of system, both considered to be conserved, are used to identify the parameter of system. If the elliptical orbit in space is considered, the conservation of linear momentum is wrong. In this paper, an identification based on the conservation of angular momentum and dynamics is presented. Compared with the classic momentum-based method, this method can get a more accurate identification result.

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Transformation from a Linear Momentum to an Angular Momentum Basis for Particles of Zero Mass and Finite Spin

Journal of Mathematical Physics ◽

10.1063/1.1704353 ◽

1965 ◽

Vol 6 (6) ◽

pp. 928-940 ◽

Cited By ~ 10

Author(s):

H. E. Moses

Keyword(s):

Angular Momentum ◽

Linear Momentum ◽

Zero Mass

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Conservation Principles for Systems With a Varying Number of Degrees-of-Freedom

Journal of Applied Mechanics ◽

10.1115/1.2789116 ◽

1998 ◽

Vol 65 (3) ◽

pp. 719-726 ◽

Cited By ~ 1

Author(s):

S. Djerassi

Keyword(s):

Angular Momentum ◽

Degrees Of Freedom ◽

Mechanical Energy ◽

Equations Of Motion ◽

Nonholonomic Systems ◽

Linear Momentum ◽

Dynamical Equations ◽

The Third ◽

Conservation Principles

This paper is the third in a trilogy dealing with simple, nonholonomic systems which, while in motion, change their number of degrees-of-freedom (defined as the number of independent generalized speeds required to describe the motion in question). The first of the trilogy introduced the theory underlying the dynamical equations of motion of such systems. The second dealt with the evaluation of noncontributing forces and of noncontributing impulses during such motion. This paper deals with the linear momentum, angular momentum, and mechanical energy of these systems. Specifically, expressions for changes in these quantities during imposition and removal of constraints are formulated in terms of the associated changes in the generalized speeds.

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