@article{ref1,
title="Effects of fore-and-aft, lateral and vertical whole-body vibration on a head-positioning task",
journal="Aviation, space, and environmental medicine",
year="1997",
author="Griffin, M. J. and Brett, M. W.",
volume="68",
number="12",
pages="1115-1122",
abstract="BACKGROUND: The performance of tasks in which the head must be positioned close to objects in a moving vehicle may be impeded by the presence of vibration. HYPOTHESES: It was hypothesized that the extent to which a head positioning task would be impeded by whole-body vibration would depend on the frequency, direction and waveform of the vibration and the posture of the body. METHOD: There were 12 subjects who participated in a laboratory experiment in which they judged the difficulty of looking through a pair of sights while exposed to low frequency vibration. We investigated 4 variables: vibration axis (fore-and-aft, lateral, vertical), vibration frequency (11 frequencies in the range 0.5 to 5.0 Hz), vibration waveform (sinusoidal vibration, one-third octave bands of random vibration), seating condition (wearing a 4-point harness, sitting without back support). RESULTS: We found that all variables affected the perceived task difficulty. Frequencies of horizontal vibration in the range 1 to 4 Hz caused most difficulty. Task difficulty was greatest with random vibration, especially with low frequency vibration in the horizontal axes. The wearing of a 4-point harness greatly reduced the perceived task difficulty during exposure to low frequency fore-and-aft vibration but increased task difficulty with higher frequencies of lateral vibration. CONCLUSIONS: Increased motion predictability and the provision of suitable support to the upper body (e.g., a harness, back support, front support) can reduce the difficulty of head positioning tasks during exposure to some types of oscillatory motion.<p /><p>Language: en</p>",
language="en",
issn="0095-6562",
doi="",
url="http://dx.doi.org/"
}