scholarly journals A Method for Direct Measurement of the First-Order Mass Moments of Human Body Segments

Sensors ◽  
2010 ◽  
Vol 10 (10) ◽  
pp. 9155-9162
Author(s):  
Yusaku Fujii ◽  
Kazuhito Shimada ◽  
Koichi Maru ◽  
Junichi Ozawa ◽  
Rong-Sheng Lu
Keyword(s):  
Direct Measurement ◽  
Human Body ◽  
Body Segments ◽  
First Order

Application of Topographical Capture Techniques for Modelling Virtual Reality

2013 ◽  
pp. 970-990
Author(s):  
Mercedes Farjas Abadía ◽  
Manuel Sillero Quintana ◽  
Pedro Ángel Merino Calvo
Keyword(s):  
Physical Activity ◽  
Virtual Reality ◽  
Human Body ◽  
Research Group ◽  
3D Models ◽  
Body Segments ◽  
The Road ◽  
Representation Systems ◽  
Human Figure ◽  
Capture Techniques

Since the dawn of time man has attempted to represent the human figure with techniques ranging from simple drawings to techniques that manage to reflect the movement of body segments. In parallel, cartographic techniques have developed very advanced capture and 3D representation systems, but even though they have been applied in recent years to other sciences, they have not been applied yet to virtual reality. The appearance of the laser acquisition systems has enabled us to acquire data without discrimination on points and to get quick 3D models. This situation allows us to work directly on the concept of surface and to analyze it from the uniqueness of the detail, compared to traditional systems which capture points for, later, imaging surfaces from them. Under this prism, a research group was formed by graduates in Physical Activity and Sport and in Cartography, in order to bring together both sciences and to improve techniques of capture and representation of the human body. The road is not completely gone, but some results have been obtained and are presented in this work.

scholarly journals Kinematics of the Foot

1982 ◽  
Vol 9 (2) ◽  
pp. 119-125 ◽  
Author(s):  
P. Allard ◽  
P.S. Thiry ◽  
M. Duhaime ◽  
G. Geoffroy
Keyword(s):  
Computer Program ◽  
Human Body ◽  
Lower Limb ◽  
Three Dimensional ◽  
Spatial Location ◽  
Geometrical Parameters ◽  
Rotating Platform ◽  
Talocrural Joint ◽  
Body Segments ◽  
Simple Movement

SUMMARY:Orthogonal stereoradiographs are frequently utilized in determining three-dimensional geometrical parameters of human body segments. They have been applied here in the estimation of the length and elongation of the ligaments of the normal foot. Three small spherical metallic markers were respectively encrusted into the tibia and fibula, the seven bones of the tarsus and into the five metatarsals of an amputed lower limb to identify uniquely their spatial location. The foot was then positioned on a rotating platform. Standardized antero-posterior and lateral radiographs were taken. Afterwards the foot was dissected and the proximal and distal insertions of most of its ligaments were located by means of spherical markers. A second series of orthogonal radiographs were taken of each of the fourteen bones. The radiographs were digitized. The length of each ligament and elongation for a simple and complex movements were calculated by means of a computer program. The results of a simple movement of rotation representing a normal 20° dorsiflexion at the talocrural joint and of complex movements of rotation simulating an abnormal high arch such as encountered in Friedreich’s ataxia are presented and discussed.

The Development, Application, and Limitations of 3D Human Simulations in Fall Accidents

2005 ◽  
Vol 49 (9) ◽  
pp. 858-861 ◽  
Author(s):  
Gary David Sloan
Keyword(s):  
Coefficient Of Friction ◽  
Human Body ◽  
Body Segment ◽  
Body Segments ◽  
Velocity Coefficient ◽  
Patterns Of Injury ◽  
Accident Site ◽  
Development Application ◽  
Fall Accidents

A tool that predicts the trajectories of linked human body segments on the basis of their inertial properties could be useful in the analysis of fall accidents. In order to be of value in forensic applications, relevant attributes of both the plaintiff and accident site must be modeled at some requisite level of fidelity. By systematically varying different attributes of the model, e.g., avatar posture, body segment velocity, coefficient-of-friction between modeled treads and footwear, it is possible to examine the likely consequences on body-segment trajectories. Trajectories and collisions can then be compared with patterns of injury, plaintiff testimony, and witness accounts.

Identification and Experimental Validation of Damping Ratios of Different Human Body Segments Through Anthropometric Vibratory Model in Standing Posture

2006 ◽  
Vol 129 (4) ◽  
pp. 566-574 ◽  
Author(s):  
T. C. Gupta
Keyword(s):  
Human Body ◽  
Damping Ratio ◽  
Physical Structure ◽  
The Body ◽  
Anthropometric Data ◽  
Body Segments ◽  
Lumped Parameter ◽  
Mass Damper ◽  
Linear Spring ◽  
Experimental Response

A 15degrees of freedom lumped parameter vibratory model of human body is developed, for vertical mode vibrations, using anthropometric data of the 50th percentile US male. The mass and stiffness of various segments are determined from the elastic modulii of bones and tissues and from the anthropometric data available, assuming the shape of all the segments is ellipsoidal. The damping ratio of each segment is estimated on the basis of the physical structure of the body in a particular posture. Damping constants of various segments are calculated from these damping ratios. The human body is modeled as a linear spring-mass-damper system. The optimal values of the damping ratios of the body segments are estimated, for the 15degrees of freedom model of the 50th percentile US male, by comparing the response of the model with the experimental response. Formulating a similar vibratory model of the 50th percentile Indian male and comparing the frequency response of the model with the experimental response of the same group of subjects validate the modeling procedure. A range of damping ratios has been considered to develop a vibratory model, which can predict the vertical harmonic response of the human body.

scholarly journals Stochastic Bioimpedance-Based Channel Model of the Human Body for Galvanic Coupling

2021 ◽  
Vol 12 (1) ◽  
pp. 117-124
Author(s):  
Aaron Roopnarine ◽  
Sean A. Rocke
Keyword(s):  
Human Body ◽  
Channel Model ◽  
Random Variable ◽  
Distribution Functions ◽  
Galvanic Coupling ◽  
Body Segments ◽  
Generalized Pareto ◽  
Body Parameter ◽  
Log Normal ◽  
Body Parameters

Abstract Human body communication (HBC) uses the human body as the channel to transfer data. Extensive work has been done to characterize the human body channel for different HBC techniques and scenarios. However, statistical channel bioimpedance characterisation of human body channels, particularly under dynamic conditions, remains relatively understudied. This paper develops a stochastic fading bioimpedance model for the human body channel using Monte Carlo simulations. Differential body segments were modelled as 2-port networks using ABCD parameters which are functions of bioimpedance based body parameters modelled as random variables. The channel was then modelled as the cascade of these random 2-port networks for different combinations of probability distribution functions (PDFs) assumed for the bioimpedance-based body parameters. The resultant distribution of the cascaded body segments varied for the different assumed bioimpedance based body parameter distributions and differential body segment sizes. However, considering the distribution names that demonstrated a best fit (in the top 3 PDF rankings) with highest frequency under the varying conditions, this paper recommends the distribution names: Generalized Pareto for phase distributions and Log-normal for magnitude distributions for each element in the overall cascaded random variable ABCD matrix.

Age Effect Investigation on Postural Dynamic Responses of Human Body

2001 ◽  
Author(s):  
Maryam Hoviattalab
Keyword(s):  
Dynamic Analysis ◽  
Human Body ◽  
Balance Control ◽  
Angular Displacement ◽  
Age Groups ◽  
Dynamic Responses ◽  
Body Motion ◽  
Body Sway ◽  
Adult Age ◽  
Body Segments

Abstract Responses of human body were studied in two adult age groups. The healthy subjects with no records of falling down or occupation in a crowded and noisy environment were elected. Mean age was 24 and 71 yrs. in young and elderly groups, respectively. Four experimental tasks were presented to subjects. Two involving flat standing with open and closed eyes and two were involving imposed disturbances. Two optoelectronic camera systems were used to measure body motion. The extents of postural sway were determined by processing the recorded data from force plate. The results were compared, and also provided the basis for kinematics analysis of body segments. For dynamic analysis, we used 3-link biomechanical model on a stationary triangular foot. Results from dynamic analysis indicated that, (a) The angular displacement of body segments was larger in elderly group, especially at the trunk; (b) The visual system had a dramatic effect on balance control, and its omission along with onset of senescence, has progressive effect, i.e. increased the amplitude and frequency of body sway, up to 2.4 and 1.5 times, respectively; (c) It has been proved that, in response to sudden stimulation, body employs certain strategy for muscle contraction. “Maximum torque, occurs in ankle, and respectively diminishes in joints, on its course toward upper segments”. The point is well consistent with the literature in this contest.

Anatomical Coordinate Systems for Human Body Segments

1978 ◽  
Vol 22 (1) ◽  
pp. 676-679
Author(s):  
Arvind J. Padgaonkar ◽  
Shirley M. Lawson ◽  
Albert I. King
Keyword(s):  
Human Body ◽  
Body Motion ◽  
Anatomical Landmarks ◽  
Coordinate Systems ◽  
Body Segment ◽  
X Ray ◽  
Body Segments ◽  
Fixed Set ◽  
Injury Research ◽  
Impact Injury

An anatomically based coordinate system is a useful tool for standardizing the placement of instrumentation on segments of the human body or human surrogate. It is suggested that this system be based upon a fixed set of anatomical landmarks that are easily located by palpation and/or x-ray. A set of coordinate systems for the head, torso and extremities is proposed. Such systems will aid investigators in comparing data acquired at different laboratories involved in impact injury research. These systems can also be used for accurately locating the center of gravity of a body segment and for describing body motion in an impact environment.

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