Garcia-Mendez Yasmin, Pearlman Jonathan L, Cooper Rory A, Boninger Michael L
Human Engineering Research Laboratories and Department of Rehabilitation Science and Technology, University of Pittsburgh, Pittsburgh, PA 15206, USA.
J Rehabil Res Dev. 2012;49(1):7-22. doi: 10.1682/jrrd.2011.02.0023.
Evidence suggests that wheelchair (WC) users are exposed to unhealthy levels of vibration during WC use. Health risks associated with vibration exposure include vertebral disc degeneration and back pain, which may consequently decrease the function and independence of WC users. Some evidence suggests that the cushions used in WCs may amplify vibrations, although conclusive evidence has not been presented in the literature. This study evaluated and compared the transmissibility of commercially available WC cushions with two laboratory test methods: (1) direct measurement of transmissibility while human subjects propelled a WC over a road course with different cushions and (2) characterization of cushions with a material testing system (MTS) combined with mathematical models of the apparent mass of the human body. Results showed that although dynamic characterization of WC cushions is possible with an MTS, the results did not correlate well with the transmissibility obtained in the WC road course. Significant differences were found for transmissibility among the cushions tested, with the air-based cushions having lower transmissibility than the foam- or gel-based cushions.
有证据表明,轮椅使用者在使用轮椅期间会接触到对健康有害的振动水平。与振动暴露相关的健康风险包括椎间盘退变和背痛,这可能会因此降低轮椅使用者的功能和独立性。一些证据表明,轮椅使用的坐垫可能会放大振动,尽管文献中尚未给出确凿证据。本研究采用两种实验室测试方法评估并比较了市售轮椅坐垫的振动传递特性:(1)在人体受试者推动轮椅在不同坐垫的道路上行驶时直接测量振动传递特性;(2)使用材料测试系统(MTS)结合人体表观质量的数学模型对坐垫进行特性表征。结果表明,尽管使用MTS可以对轮椅坐垫进行动态特性表征,但结果与在轮椅道路测试中获得的振动传递特性相关性不佳。在所测试的坐垫中,振动传递特性存在显著差异,充气坐垫的振动传递特性低于泡沫或凝胶坐垫。