Keyur Hirpara1, Hemant Nagarsheth2 and V M Daiya3
¹Department of Mechanical Engineering, Institute of Technology,Nirma UniversityAhmedabad, Gujarat ² Mechanical Engineering Department, SVNIT, Surat, Gujarat ³ Mechanical Engineering Department, SVNIT, Surat, Gujarat

Frequent and prolonged expose of human body to vibrations can induce back pain and physical disorder and degeneration of tissue. The biomechanical model of human lower limbs are modeled as a three degree of freedom linear spring-mass-damper system to estimate forces and frequencies. Then three degree of freedom system was analysed using state space method to find natural frequency and mode shape. A program was develop to solve simplified equations and results were plotted and discussed in detail. The mass, stiffness and damping coefficient of various segments are taken from references. The optimal valuesof the damping ratios of the body segments are estimated, for the three degrees of freedom model. At last resonance frequencies are found to avoid expose of lower limbs to such environment for optimum comfort

Bayesian statistics, Modal parameters, Eigen sensitivity, Structural modification, MCMC