Distinction between center of mass and center of gravity—Oscillation of rod‐shaped satellite as an example

The purpose of this study was to examine grand battement devant at the barre, in the center, and traveling through space. The primary focus was to consider weight transfer in three conditions: from two feet to one foot for the barre and center conditions, and from one foot to the other foot in traveling. Forty female dancers volunteered (mean age 30.0 ± 13.0 yrs) and were placed in three groups: beginner (n = 12), intermediate (n = 14), and advanced (n = 14). Data were collected with a 7-camera Vicon motion capture system using a Plug-in Gait Full Body Marker set and with two Kistler force plates. Dancers executed five grand battement devant in each of three conditions in randomized order: at the barre in 1st position, in the center in 1st position, and traveling through space. Four variables were investigated: center of gravity of the full trunk, center of gravity of the pelvis, center of gravity of the upper trunk, and center of mass. Data were analyzed in three intervals—stance to battement initiation (STN to GBI), initiation to battement peak (GBI to GBP), and peak to end (GBP to END)—and in the x-axis and y-axis. The main effect condition was significant for all four variables in both x-axis and y-axis (p<0.001). There were no significant differences for training and no significant condition 3 training interactions. Condition was significant for all three intervals (STN to GBI, GBI to GBP, and GBP to END) for all four variables in both axes (p<0.01). Dance educators might consider the importance of allocating sufficient time in dance practice to each of the three conditions—barre, center, and traveling—to ensure development of a variety of motor strategies for weight transfer.

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Center of Gravity, Center of Mass,Centroids

Statics – Formulas and Problems ◽

10.1007/978-3-662-53854-8_2 ◽

2016 ◽

pp. 29-44

Author(s):

Dietmar Gross ◽

Wolfgang Ehlers ◽

Peter Wriggers ◽

Jörg Schröder ◽

Ralf Müller

Keyword(s):

Center Of Mass ◽

Center Of Gravity ◽

Gravity Center

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Some “laws” of gastropod shell form

Paleobiology ◽

10.1017/s0094837300005261 ◽

1977 ◽

Vol 3 (2) ◽

pp. 196-206 ◽

Cited By ~ 87

Author(s):

Robert M. Linsley

Keyword(s):

Center Of Mass ◽

Mantle Cavity ◽

Center Of Gravity ◽

The Body ◽

Water Current ◽

Gastropod Shell ◽

Shell Form ◽

Body Whorl ◽

Anterior Posterior ◽

Anterior Posterior Axis

Five generalizations derived from the shell form of prosobranch gastropods are developed. (1) A univalve of more than one volution whose aperture lies in a plane that passes through the axis of coiling does not live with the aperture parallel to the substrate. (2) A univalve of more than one volution whose aperture lies in a plane that is tangential to the body whorl does live with the plane of the aperture parallel to the substrate. (3) Gastropods with tangential apertures, when extended, support the shell so that the center of mass of the shell and its contents is over the midline of the cephalopedal mass; this balancing of the shell may be accomplished either by regulatory detorsion, by inclination or by a combination thereof, to keep the center of gravity of the shell as low as possible. (4) Angulations or re-entrants in the gastropod aperture are usually indicative of inhalent or exhalent areas; inhalent areas are directed as far anteriorly as possible. (5) Gastropods having elongated apertures possess only a single gill and develop a water current through the mantle cavity from anterior to posterior along the long axis of the aperture; this axis is subparallel to the anterior-posterior axis of the foot.These generalizations are then used as the basis for some deductive interpretations of behavioral modes of Paleozoic Gastropoda.

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Dental Malocclusion and Its Relation to the Podal System

Frontiers in Pediatrics ◽

10.3389/fped.2021.654229 ◽

2021 ◽

Vol 9 ◽

Author(s):

María E. Cabrera-Domínguez ◽

Antonia Domínguez-Reyes ◽

Manuel Pabón-Carrasco ◽

Ana J. Pérez-Belloso ◽

Manuel Coheña-Jiménez ◽

...

Keyword(s):

Sagittal Plane ◽

Scientific Evidence ◽

Center Of Mass ◽

Class Ii ◽

Center Of Gravity ◽

Dental Occlusion ◽

Class Ii Malocclusion ◽

Class Iii ◽

Foot Posture ◽

The Right

Background and Objective: This study analyzes the possibility that Stomatognathic and Postural systems are related by muscle chains. Malocclusion may influence the posture, contact between the foot and the ground, center of mass, footprint or vice-versa. This study aimed to verify whether there is a relationship between dental occlusion and podal system.Materials and Methods: A cross-cutting, descriptive study was carried out on 409 children (222 boys and 187 girls) between 8 and 14 years old. Dental occlusion was assessed on the sagittal plane (Angle's classification) the contact between the foot and the ground and the center of mass were evaluated using a stabilometric platform.Results: There was a statistically significant relationship between the plantigrade phase, the contact surface area and center of gravity. There was a prevalence of molar and canine Angle's class II malocclusion. In molar class II, an anterior center of gravity was predominant, in class I it was centered and in class III, it was posterior. There was significant correlation between malocclusions and the FPI (foot posture index) of the left foot and the height of the scaphoid in the right foot (P < 0.001).Conclusions: Some authors agree with our results. There is still much uncertainty in terms of showing a relationship between both systems. In addition, there is scarce scientific evidence on the topic. Some kind of relationship between the two systems has been proven. Studies that evaluate a group of subjects in a longitudinal manner are necessary to enable the changes taking place in both systems to be defined.

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Center of Gravity, Center of Mass, Centroids

Engineering Mechanics 1 ◽

10.1007/978-3-540-89937-2_5 ◽

2009 ◽

pp. 87-114

Author(s):

Dietmar Gross ◽

Werner Hauger ◽

Jörg Schröder ◽

Wolfgang A. Wall ◽

Nimal Rajapakse

Keyword(s):

Center Of Mass ◽

Center Of Gravity ◽

Gravity Center

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C4 CENTER OF GRAVITY AND CENTER OF MASS

BIOS Instant Notes in Sport and Exercise Biomechanics ◽

10.4324/9780203488300-21 ◽

2007 ◽

pp. 157-164

Keyword(s):

Center Of Mass ◽

Center Of Gravity

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Center of Gravity, Center of Mass, Centroids

Engineering Mechanics 1 ◽

10.1007/978-3-642-30319-7_5 ◽

2013 ◽

pp. 89-116

Author(s):

Dietmar Gross ◽

Werner Hauger ◽

Jörg Schröder ◽

Wolfgang A. Wall ◽

Nimal Rajapakse

Keyword(s):

Center Of Mass ◽

Center Of Gravity ◽

Gravity Center

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Analysis on non-stationary gyroscopes and their application in measurement technology

Journal of Physics Conference Series ◽

10.1088/1742-6596/2091/1/012006 ◽

2021 ◽

Vol 2091 (1) ◽

pp. 012006

Author(s):

A I Andreev ◽

A P Perekrestov

Keyword(s):

Center Of Mass ◽

Interesting Case ◽

Center Of Gravity ◽

Point Of View ◽

Measurement Technology ◽

Measuring Instruments ◽

Body Of Revolution ◽

Gravitational Fields ◽

First Case ◽

Working Medium

Abstract In this work, the main subjects of research are: 1) analysis of the process of rotation of a Chinese top on a flat surface, 2) analysis of the main dependencies and an explanation of the rise of the center of gravity of the top during rotation due to nonlinear friction and the resulting force of the overturning top on the upper axis. Also, an analytical study of the motion of the top along the plane and the laws of rotation was carried out, the rotation of the top was analyzed from the point of view of asymmetry during rotation. The top-top spinning top is an interesting case of raising the center of gravity during rotation. The simplest model of a Chinese top can be a dynamic symmetric inhomogeneous ball, the center of mass of which lies on the axis of dynamic symmetry, but does not coincide with its geometric center. The precession of the Chinese top is based on dry friction. The occurrence of a gyroscopic deflection moment is based on the frictional force. Considering the simplest top-type top, one can distinguish the main forces acting on this body, as well as its characteristics that determine the precession. Based on this fact, it is possible to propose the use of this body of revolution as a working medium for instruments such as tribometers and gravimeters. In the first case, this makes it possible to increase the accuracy of the device, in the second, to create a new scheme for measuring gravitational fields. The relevance of this work is the analysis of the rotation of the Chinese top and the possibility of its use in measuring instruments.

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System of differential equations of aircraft spatial motion dynamics with arbitrary tensor of inertia and center of gravity position

VESTNIK of the Samara State Aerospace University ◽

10.18287/2541-7533-2021-20-2-7-18 ◽

2021 ◽

Vol 20 (2) ◽

pp. 7-18

Author(s):

D. V. Vereshchikov

Keyword(s):

Differential Equations ◽

Center Of Mass ◽

Center Of Gravity ◽

The Body ◽

Spatial Motion ◽

System Of Differential Equations ◽

Aircraft Flight ◽

Analytic Expressions ◽

Tensor Of Inertia ◽

Arbitrary Tensor

Derivation of analytic expressions making up the basis of a mathematical model of aircraft flight dynamics for the differential equations describing the change in the rate of roll, yaw and pitch, as well as flight velocity components in projections on the body-fixed coordinate axes is presented. The origin of the coordinate system does not in general coincide with the center of mass of the plane, and the axes are not the same as its main central axes of inertia. The differential equations for angular and linear velocities are reduced to the form convenient for the use of numerical methods and computer systems and make it possible to get consistent results of simulating the dynamics of aircraft spatial motion with an arbitrary tensor of inertia and center of gravity position.

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