CONCAVE Research Centre, Department of Mechanical and Industrial Engineering, Concordia University, 1455 Blvd. de Maisonneuve West, Montreal, Quebec, H3G 1M8, Canada.
Ind Health. 2010;48(5):682-97. doi: 10.2486/indhealth.mswbvi-25.
The vibration transmission to the lumbar and thoracic segments of seated human subjects exposed to whole body vibration of a vehicular nature have been mostly characterised without the back and hand supports, which is not representative of general driving conditions. This non-invasive experimental study investigated the transmission of vertical seat vibration to selected vertebrae and the head along the vertical and fore-aft axes of twelve male human subjects seated on a rigid seat and exposed to random vertical excitation in the 0.5-20 Hz range. The measurements were performed under four different sitting postures involving combinations of back support conditions and hands positions, and three difference magnitudes of vertical vibration (0.25, 0.5 and 1.0 m/s(2) rms acceleration). The results showed significant errors induced by sensor misalignment and skin effects, which required appropriate correction methodologies. The averaged corrected responses revealed that the back support attenuates vibration in the vertical axis to all the body locations while increasing the fore-aft transmissibility at the C7 and T5. The hands position generally has a relatively smaller effect, showing some influences on the C7 and L5 vibration. Sitting without a back support resulted in very low magnitude fore-aft vibration at T5, which was substantially higher with a back support, suggestive of a probable change in the body's vibration mode. The effect of back support was observed to be very small on the horizontal vibration of the lower thoracic and lumbar regions. The results suggest that distinctly different target body-segment biodynamic functions need to be defined for different support conditions in order to represent the unique contribution of the specific support condition. These datasets may then be useful for the development of biodynamic models.
人体坐姿下暴露于车辆全身振动时，对腰椎和胸椎节段的振动传递研究大多是在没有背部和手部支撑的情况下进行的，这并不代表一般的驾驶条件。本非侵入性实验研究调查了在刚性座椅上的 12 名男性人体坐姿下，垂直座椅振动通过垂直和前后轴传递到选定的脊椎和头部的情况，这些人体暴露于 0.5-20 Hz 随机垂直激励中。在涉及背部支撑条件和手部位置组合的四种不同坐姿下，以及三种不同大小的垂直振动（0.25、0.5 和 1.0 m/s2 rms 加速度）进行了测量。结果表明，传感器错位和皮肤效应会引起显著误差，需要采用适当的校正方法。平均校正响应表明，背部支撑会衰减垂直轴上所有身体部位的振动，同时增加 C7 和 T5 的前后传递率。手部位置通常具有相对较小的影响，对 C7 和 L5 的振动有一定的影响。不使用背部支撑时，T5 的前后振动幅度非常低，但使用背部支撑时会大幅增加，表明可能改变了身体的振动模式。背部支撑对下胸椎和腰椎区域的水平振动的影响很小。结果表明，为了代表特定支撑条件的独特贡献，需要为不同的支撑条件定义明显不同的目标身体节段生物动力学功能。这些数据集可能有助于生物动力学模型的开发。
