Analysis of human body response to vibration using multi-body dynamics method

Abstract

Research on how vibration affects the human body has indicated that vibration of the whole body can cause spinal injury, low back pain, and uncomfortable feelings and interferecan with working efficiency, safety, and health. The characteristics of human response to vibration need to be understood to reduce these effects of vibration on humans. Experiments in humans for such investigations have limitations. A viable alternative involves approximating the human body using a mathematical model and analysing the desired behaviour of the model. This study establishes a seated human body vibration model using the multi-body dynamics method. The dynamic equations of motion of the mechanical structure are based on Kane's equations as formulated by Huston et al. [24]. The equations are then coded into a computer program and solved using fourth-order Runge-Kutta methods. The developed human body model is employed to examine the biodynamic response of the human body under vertical vibration and to measure the natural frequency and input-output acceleration ratio (transmissibility) of each individual segment received. The multi-body dynamics results closely correspond to the experimental results. The analysis cost of multi-body dynamics method is very low. The procedures described herein contribute to efforts to optimize seat design and analyse human body comfort.