Response of human subject while working in agricultural conditions

Human body is exposed to vibration in daily life activities like travelling, heavy machinery work, agriculture operations etc.The aim of present study is to evaluate the effect of whole body vibration on various human body segments. A three layer 3D CAD model has been modelled according to 95th percentile Indian human male anthropometric data with three different layers for defining the properties of human bone, skin and muscles, respectively. Human model has been excited at RMS value of 0.5, 1.0 and 1.5 m/s in a frequency range from 0-20 Hz. 3D model of farm tractor seat has been also developed using reverse engineering. Human model and tractor seat have been assembled with each other and RMS value ranging from 0.5-1.5 m/s has been applied on the seat to find out the seat to head transmissibility. Damping ratio of human body has been considered to be 0.2, 0.3 and 0.5. The seat has been considered with three spring stiffness 0.3, 0.55 and 0.7 kg/mm for suspension system. It has been found that maximum deformation occurs at head and primary resonance frequency has been found to be in the range of 4-6 Hz.