A review of the transmission of translational seat vibration to the head

Published studies of the transmission of translational seat vibration to the heads of seated subjects are reviewed in order to determine the variations in transmissibility. The review is restricted to vibration having the same direction at the seat and the head: (a) transmission between fore-and-aft seat vibration and fore-and-aft head motion, (b) transmission between lateral seat vibration and lateral head motion, and (c) transmission between vertical seat vibration and vertical head motion. Only studies reporting transmissibilities from six or more subjects are included in the review. Transmissibilities are shown for all studies included: 10 studies with fore-and-aft seat vibration, 14 studies with lateral seat vibration and 46 studies with vertical seat vibration. The studies involved a wide range of experimental conditions, including different sitting postures, various types of subject and various locations for measuring vibration on the head. The conditions of each experiment are tabulated. The transmissibility data have been used to calculate the median, interquartile range and range of transmissibility for each axis of vibration. (C) 1998 Academic Press.