抄録
In vehicle systems or construction machinery occupational drivers might be exposed to vibration for a long time. This may cause ache of the spine such as low back pain. Therefore, it is necessary to evaluate the influence of vibration on the spinal column. For this purpose, the vibration experiment is conducted to measure in detail the response of the spinal column. Modal parameters of upper human bodies are identified by using measured transmissibilities. As the results, three modes are observed within the range 4Hz to 20Hz. The first mode is characterized by the composition in the sagittal plane of the head rotation and the spinal bending. The second mode shows the relative motion of the lower trunk (lumbar vertebrae). The significantly large motion of the sacrum might cause the increase of the spinal load, the lowest intervertebral disc showing the largest deformation. Finally, the main characteristic of the third mode is the neck deformation. In Addition, the human transmissibilities are compared using different averaging methods.
