Blood Ryan P, Yost Michael G, Camp Janice E, Ching Randal P
a Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington , Seattle , Washington.
J Occup Environ Hyg. 2015;12(6):351-62. doi: 10.1080/15459624.2014.989357.
Long-term exposure to seated whole-body vibration (WBV) is one of the leading risk factors for the development of low back disorders. Professional bus and truck drivers are regularly exposed to continuous WBV, since they spend the majority of their working hours driving heavy vehicles. This study measured WBV exposures among professional bus and truck drivers and evaluated the effects of seat-suspension designs using simulated field-collected data on a vibration table. WBV exposures were measured and compared across three different seat designs: an air-ride bus seat, an air-ride truck seat, and an electromagnetically active (EM-active) seat. Air-ride seats use a compressed-air bladder to attenuate vibrations, and they have been in operation throughout the transportation industry for many years. The EM-active seat is a relatively new design that incorporates a microprocessor-controlled actuator to dampen vibration. The vibration table simulated seven WBV exposure scenarios: four segments of vertical vibration and three scenarios that used field-collected driving data on different road surfaces-a city street, a freeway, and a section of rough roadway. The field scenarios used tri-axial WBV data that had been collected at the seat pan and at the driver's sternum, in accordance with ISO 2631-1 and 2631-5. This study found that WBV was significantly greater in the vertical direction (z-axis) than in the lateral directions (x-and y-axes) for each of the three road types and each of the three types of seats. Quantitative comparisons of the results showed that the floor-to-seat-pan transmissibility was significantly lower for the EM-active seat than for either the air-ride bus seat or the air-ride truck seat, across all three road types. This study also demonstrated that seat-suspension designs have a significant effect on the vibrations transmitted to vehicle operators, and the study's results may prove useful in designing future seat suspensions.
长期暴露于坐姿全身振动（WBV）是导致下背部疾病的主要风险因素之一。职业巴士和卡车司机经常暴露于持续的WBV中，因为他们大部分工作时间都在驾驶重型车辆。本研究测量了职业巴士和卡车司机的WBV暴露情况，并使用在振动台上模拟现场采集的数据评估了座椅悬架设计的效果。在三种不同的座椅设计中测量并比较了WBV暴露情况：一种空气悬架巴士座椅、一种空气悬架卡车座椅和一种电磁主动（EM主动）座椅。空气悬架座椅使用压缩空气气囊来减弱振动，并且它们已经在整个运输行业运行多年。EM主动座椅是一种相对较新的设计，它采用微处理器控制的致动器来抑制振动。振动台模拟了七种WBV暴露场景：四段垂直振动以及三种使用不同路面现场采集的驾驶数据的场景——城市街道、高速公路和一段崎岖道路。现场场景使用了根据ISO 2631 - 1和2631 - 5在座椅座板和驾驶员胸骨处采集的三轴WBV数据。本研究发现，对于三种道路类型中的每一种以及三种座椅类型中的每一种，垂直方向（z轴）的WBV明显大于横向方向（x轴和y轴）。结果的定量比较表明，在所有三种道路类型中，EM主动座椅的地板到座椅座板的传递率明显低于空气悬架巴士座椅或空气悬架卡车座椅。本研究还表明，座椅悬架设计对传递给车辆操作员的振动有显著影响，并且该研究结果可能对未来座椅悬架的设计有用。
