Evaluation of damping coefficients of a Vibrartory model of a Human Body

Abstract

In this work, modeling of vibratory system of human body and its study under standing posture have been presented. The human body is developed as a spring-massdamper system. A generalized procedure for modeling of human body through anthropomorphic model has been developed and assumptions are clearly stated. The model parameters are obtained through the mass, stiffness and damping values of the segment of the anthropomorphic model. The mass and stiffness values of the segments are obtained using the anthropometric data and elastic moduli of bones and tissues. An initial effort was made to consider the viscosity of blood and other fluids in predicting the behavior of the multi-degree damped vibratory systems. Damping is incorporated by assigning some appropriate clearance values to the individual segments. The damping coefficients and damping ratio values of individual segments are obtained using anthropometric data and viscosity of blood. The validation of modeling procedure is done by first developing the model for a 50th percentile US male and comparing the response with some experimental response data of US male available in the literature. In addition this work also presents the frequency response of different parts of the body due to constant force excitation at foot and at hands. The thesis seems to have achieved its objective with a fair success. On the basis of this work, vibratory models of individuals can be framed which can predict the actual frequency response with reasonable accuracy.