The absorbed power characteristics of seated body exposed to whole-body vibration along the individual and combined fore-aft (x), lateral (y) and vertical (z) axes are investigated through measurements of body-seat interactions at the two driving-points formed by the body and the seat-pan, and upper body and the seat backrest. The experiments involved two levels of back support (no back support and vertical backrest) and two levels of broad-band vibration with nearly constant acceleration power spectral density in the 0.5-20 Hz frequency range applied along the individual x-, y- and z- axis (0.25 and 0.4 m/s~2 rms acceleration), and along the three-axis (0.23 and 0.4 m/s~2 rms acceleration along each axis). The biodynamic responses, measured at the seat-pan and the backrest are applied to characterize the total seated body's energy transfer along each axis. Furthermore, an alternative frequency response function method H_v is employed to capture the coupling in the seated body responses to uncorrelated multi-axis vibration. The total vibration absorbed power responses to simultaneous x, y and z -axis vibration are subsequently derived as the summation of vibration absorbed power along the individual axis within each one-third frequency band. The mean responses measured at the seat-pan suggest strong effects of the back support, and the direction and magnitude of vibration. The total vibration power absorbed by the seated body is further estimated under a multi-axis vibration environment of four different work vehicles. The results suggest that total average power absorbed under reported vehicular vibration varies with the effective acceleration in a nearly quadratic manner.
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机译：通过测量两个驱动点处的座椅与座椅之间的相互作用，研究了座椅车身在沿单个和组合的前后（x），横向（y）和垂直（z）轴受到全身振动的情况下的吸收功率特性。由车身和座板，上身和座椅靠背组成。实验涉及两个级别的靠背支撑（无靠背和垂直靠背）和两个级别的宽带振动，分别在沿x，y和z方向施加的0.5-20 Hz频率范围内具有几乎恒定的加速功率谱密度-轴（0.25和0.4 m / s〜2 rms加速度）和沿三轴（每个轴0.23和0.4 m / s〜2 rms加速度）。在座板和靠背处测得的生物动力响应被用于表征整个坐体沿每个轴的能量传递。此外，采用另一种频率响应函数方法H_v来捕获就座人体对不相关多轴振动的响应中的耦合。随后得出对同时发生的x，y和z轴振动的总振动吸收功率响应，作为每个三分之一频带内沿各个轴的振动吸收功率之和。在座便器上测得的平均响应表明了靠背的强烈作用以及振动的方向和幅度。在四个不同的作业车辆的多轴振动环境下，进一步估计了座椅主体吸收的总振动功率。结果表明，在报告的车辆振动下吸收的总平均功率随有效加速度的变化几乎呈二次方变化。
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