Effect Of Vehicle Vibration On Human Body – RIT Experience

Vibration has become an important consideration in engineering. Development of industries and vehicles make the subject even more important. In today’s world every family has a car. There for it becomes essential to study the phenomenon of vehicle vibration and it's effects on humans. Man, as a mechanical system, is extremely complex and his mechanical properties readily undergo change. Effect of vibration on human body as a mechanical and biological system is very complex phenomenon. There is limited reliable information on the magnitude of the forces required to produce mechanical damage to the human body. To avoid damage to humans while obtaining such data, it is necessary to use experimental animals for most studies on mechanical injury. However the data so obtained must be subjected to careful scrutiny to determine the degree of their applicability to human, which differs from animals not only in size but in anatomical and physiological structure as well. It is very difficult to obtain reliable data on the effect of mechanical forces on the performance of various tasks and on subjective responses to these forces largely because of wide variation in the human being in both physical and behavioral respects. Measurement of some of the mechanical properties of men is however often practicable since only small forces are needed for such work. In the present paper, vehicle vibration analysis is carried out. For this analysis it was proposed to perform vibration tests for different vehicle models. Vibration data for each model at three different road and speed conditions were taken by using Fast Fourier Transform (FFT). The spectrum obtained is used for further analysis for determining acceleration levels at different frequencies. The readings obtained from Fast Fourier Transform (FFT) are used to draw the graphs of frequency Vs acceleration. Firstly the effect of road condition on acceleration level of vibration is predicted with the help of these graphs. The effect of speed condition on acceleration level is also studied. By referring ISO 2631, human comfort charts, the comment is made regarding the acceleration level. Mostly lower frequencies of vibrations ranging from 0 to 80 Hz are affecting on human body. From the results, optimum relationship between acceleration level of vibration and human comfort is drawn.