title: Discomfort of seated persons exposed to low frequency lateral and roll oscillation: effect of seat cushion.
abstract: The discomfort caused by lateral oscillation, roll oscillation, and fully roll-compensated lateral oscillation has been investigated at frequencies between 0.25 and 1.0 Hz when sitting on a rigid seat and when sitting on a compliant cushion, both without a backrest. Judgements of vibration discomfort and the transmission of lateral and roll oscillation through the seat cushion were obtained with 20 subjects. Relative to the rigid seat, the cushion increased lateral acceleration and roll oscillation at the lower frequencies and also increased discomfort during lateral oscillation (at frequencies less than 0.63 Hz), roll oscillation (at frequencies less than 0.4 Hz), and fully roll-compensated lateral oscillation (at frequencies between 0.315 and 0.5 Hz). The root-sums-of-squares of the frequency-weighted lateral and roll acceleration at the seat surface predicted the greater vibration discomfort when sitting on the cushion. The frequency-dependence of the predicted discomfort may be improved by adjusting the frequency weighting for roll acceleration at frequencies between 0.25 and 1.0 Hz.
authors.affiliation: Human Factors Research Unit, Institute of Sound and Vibration Research, University of Southampton, Highfield, Southampton SO17 1BJ, United Kingdom.
authors.forename: George F
authors.initials: GF
authors.lastname: Beard
authors.affiliation: Human Factors Research Unit, Institute of Sound and Vibration Research, University of Southampton, Highfield, Southampton SO17 1BJ, United Kingdom. Electronic address: m.j.griffin@soton.ac.uk.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Griffin
mesh_terms: D000054:Acceleration; D000293:Adolescent; D000328:Adult; D001416:Back Pain / Q000503:physiopathology; D004867:Equipment Design; D006804:Ergonomics / Q000379:methods*; D006801:Humans; D007866:Leg / Q000503:physiopathology; D008297:Male; D018986:Motor Vehicles; D010147:Pain Measurement; D011187:Posture / Q000502:physiology*; D014732:Vibration / Q000009:adverse effects*
keywords: Discomfort; Seating; Vibration