In modern technologically based society, recognition of the fundamental importance of dimensional measures of human population has increased. This is reflected in the observation that about 85% of large anthropometric studies worldwide have been conducted over time.
RESULTS OF LARGE-SCALE ANTHROPOMETRIC SURVEYS
PRECONDITIONS
This is because sitting position determines the curvature of the spine, which in turn affects sitting height. In particular, in large-scale anthropometric research, carelessness on this point can often be observed.
MEASURING INSTRUMENTS
The considerable amount of information gathered further allows the combination of anthropometric data
Here again we discover the concept of the average man, and practical measurements show it to be just as unworkable as before. Problems similar to those of the textile industry can also be found in the automotive industry.
CONCLUSION
This type of comparison raises the question of the extent to which it makes sense to adapt one thing to all the world's populations using special adaptation provisions. Perhaps it would be better from an economic and technical point of view to divide humanity into two groups and serve them with two sizes of product, be it a car or something else.
LITERATURE
FBWM 76-2, Bonn
- SOURCES OF ANTHROPOMETRIC DIFFERENTIATION
- WHICH POPULATIONS NEED ANTHROPOMETRIC DESCRIPTION?
- WHICH MEASUREMENTS ARE NEEDED?
- METHODS OF OBTAINING AND PRESENTING THE DATA
- CONCLUSION
Current areas of the Air Force Aerospace Medical Research Laboratory (AFAMRL) Anthropometric Data Bank include 34 separate surveys (Table 1). In many cases, it is felt that the research has theoretical implications, ie, the study of therapy.
AVAILABLE MOTIONS INVENTORY NAME
CLIENT#: 1021
DATE OF BIRTH: 09-18-58 SEX: MALE
DATE OF PROCEDURE: 08-05-80 SET UP: HHEELCHAIR
SEATED ELBOH HEIGHT: (LEFT) 68.8 SEATED ELBOW HEIGHT: (RIGHT) 71.2
GROUP SUBTESTS MEAN Z-SCORES STANDARDS MEAN Z-SCORES
DESCRIPTION OF SPECIFIC STUDIES IN MORPHOLOGICAL BIOMETRY The characteristics of the human body studies in morphological
These sciences need information about the characteristics of the human body, as it varies intra- and inter-individually, and under static and dynamic conditions. If you introduce the time factor, the dynamic behavior of the human body is studied. In this context, the elements of the person (anatomical points) and the elements of the system (commands) are calculated according to a common reference system (Fig. 7).
In the latter case, the use of techniques for measuring the human body in three-dimensional space significantly enriches our knowledge of the dynamic aspects of growth. The measurement of masses and the effects of accelerations on the masses of the human body is carried out by known methods in biometrics and biomechanics.
DATA PROCESSING AND HANDLING
Usually, measurements of the inertial properties of the human body are made by the double oscillation method application of the Huygens theorem. The location of the center of mass itself, given by measuring the period of oscillation of the pendulum and the masses. man + pendulum), is defined according to its location in a three-rectangular frame of reference. The experimental values of mass and oscillation period of the pendulum are also transformed into values of moments of inertia and positions of the center of mass.
In other words, the data results of a survey stored in ERGODATA can be handled individually, but they can also be used to create samples (thanks to the conversation mode) in relation to other data or other surveys stored in the bank. Specific software makes it possible to create models of the human body or human-machine system that can vary in time and space.
CONCLUS ION
BIOMECHANICAL COMPUTER MODELING FOR THE DESIGN AND EVALUATION OF ~JORK STATIONS
This model divides the operator's body into 15 mass segments for dynamic analysis of the body's response to acceleration. The problems of using computer simulations for crew station design and evaluation arise from inadequacies in the databases being modeled, forgetting assumptions made in the modeling process, inappropriate use of the computer model, failure to verify analysis, and failure to model the to validate. Statistics books teach us that the error increases as the predicted value moves away from the center of the modeled distribution, and increases non-linearly, until outside the upper and lower ranges of the data, the potential for error is so great that the model is worthless. .
Using the model outside the realm of the modeled data is against good engineering practice. Due to the complexity of computer models, it sometimes happens that a combination of input variables interact in such a way that they produce erroneous results.
SOLUTIONS TO BIOMECHANICAL MODELING PROBLEMS
In summary, biomechanical databases cannot be easily combined into a single model. Existing databases were collected for purposes other than general computer modeling. The force that can be applied to a control is a function of the location of the control and the direction of the required force. In summary, most biomechanica1 databases were not collected for computer modeling purposes.
They have neither the number of variables nor the right definition of variables for computer modeling. This not only increases the accuracy and usability of the model, but it also simplifies the model development.
INTRODUCTION
DYNAMIC STRENGTH
Static strength was defined as the maximum force that muscle can exert isometrically in a single voluntary effort. These tests can be worthwhile because they are easy to administer, require little equipment, and can be completed in two minutes. Their disadvantages lie in the fact that no partial credit is awarded and a relatively small sample of the body's muscle groups are tested.
Other measurements of dynamic strength have been made using a different approach than that reported by Fleishman. Such techniques have been reported by Doss and Karpovich (1965) who measure muscle strength during isotonic movements, both concentric and eccentric.
EQUIPMENT USED TO MEASURE DYNAMIC STRENGTH
In addition, they present slightly less strenuous versions of these tests that meet the needs of women. It should be noted that some of the tests described above may not be considered valid measures of strength but rather measures of endurance by some investigators.
STATIC STRENGTH
Static strength has also been defined as the ability to produce torque or force with maximal voluntary isometric muscle effort. At the same time, some researchers reported a high correlation between the two measures (Asmussen et al. 1965).
EQUIPMENT USED TO MEASURE DYNAMIC STRENGTH
TESTING PROCEDURES STATIC
AYOUB (3) Speeds are normally
- VARIABLES AFFECTING STRENGTH MEASUREMENTS
Instruments and techniques for measuring muscular strength and endurance in the human body. Its effect is similar to the force with which a log resting on a handle would act in the dead axis (Fig. l), perpendicular to the line between the handle and the floor support. In the 'dead weight' analogy, the force depends only on the weight of the log and where its center of mass is relative to the floor support and handle.
The force is in the live axis (Figure 1), which is the line between the center of pressure on the ground and the handle. If we measure the vertical or horizontal components of force during the maximum static lifts or pulls with different placements of arms and legs (total) (Figure 2), we can calculate the proportions of own weight of the variance of strength, which are the result of differences in weight and height in the population (Pheasant, 1977). .
PUSH-
In the general case of effort in any direction, the man in Figure 3 exerts a force that has LIFT and THRUST components. Torque can be significant when the arms are separated in the sagittal plane, but was negligible in the experiments for which the results are presented.
BACK
The intersection at the base of the PSD (LIFT/W= -1) is equal to the horizontal distance from the center of gravity to the handle as a fraction of the handle height. Lines obtained in two positions that differed by a shift in the subject's center of gravity (a-b), but the centers of gravity of hands and feet (h/b) did not change. The effect of shifting the center of gravity was to change the point of intersection of the line containing the heads of the vectors.
By means of a large balance board, the limiting anterior and posterior locations of the center of gravity were determined for each combination of foot and hand placement. Restrictive ESEs apply when the center of pressure on the feet is at the anterior limit of the foot base, while the center of gravity is at the posterior limit, and vice versa.
TOE POSN
TCMJ
Each force effort was analyzed at the peak portion of the force-effort curve and at the maintained level. Additionally, the percentage of force exerted was calculated as a function of each subject's 100% average and as a function of the greatest effort. The table contains two group correlation coefficients for each effort (along with confidence limits): one related to the percentage of force in the sustained part of the effort, the other to the maximal part of the effort.
The correlation coefficients for the maintained and maximal portions of the effort appeared to follow each other quite closely. All group correlation coefficients were significant, supporting the hypothesis of the individual relationship between strength building and the portion of strength exercised.
ON-SITE MAXIMUM VOLUNTARY EXERTION MEASUREMENTS AND JOB EVALUATION
Kamon
INTRODUCTION
OBJECTIVES
Back extensor MVC was measured similar to the technique described by Poulsen and Jorgensen (1971). Elbow flexion was performed in a sitting position with the shoulder and elbow joint held at 900. • The shoulder flexion was measured either standing or sitting. The band is attached to the wrist and the pull is performed with the elbow fully extended, either in a sitting position (1350.
In the steelworks it was done by means of a board connected by a cable from its center to the dynamometer. In the chemical plant, a tray (50 x 40 x 12 cm) with recessed lips was used to grip with a cable attachment from the center to the dynamometer.
RESULTS AND DISCUSSION Maximal Voluntary Contraction
The board (60 x 50 cm) was grasped at the sides and pulled 50 cm above the floor with the center of the board (drawing line) approximately 25 cm in front of the ankle. Several models of the hip joint existed and were analyzed as a statically determined problem. There are at least eight lower limb models of varying degrees of complexity to simulate human gait.
It can be used to study large displacements of the spine in lateral bending or buckling. H = Horizontal displacement of the hands from a point on the ground, halfway between the ankles (em).
MEASURED STRENGTH ~- N
USAF DRAWING BOARD MANIKINS
One of the more recent design tools developed from anthropometric data is the series of USAF Two-Dimensional Drawing Board Manikins. Fifth, 50th, and 95th percentile male mannequins were designed in accordance with the anthropometry of the USAF-rated pilots projected to the 1980-90 period. Considerable additional anthropometric data was used to establish the overall sizes and mobility of the mannequins.
Several dimensions derived by Snyder, et al (1972), were used to establish the relationships between and limits of mobility of the major trunk segments. The centers of rotation of the head, neck and torso correspond to the atlanto-occipital joint, the internal spaces between the 7th cervical vertebra and the first thoracic vertebra, the 8th and 9th thoracic vertebrae, the 3rd vertebra and 4th lumbar and hip joint.
