Effects of elastic seats on seated body apparent mass responses to vertical whole body vibration |
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| Authors: | K.N. Dewangan Pierre Marcotte A. Shahmir |
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| Affiliation: | 1. Department of Agricultural Engineering, North Eastern Regional Institute of Science &2. Technology, Nirjuli, India;3. Institut de recherche Robert-Sauvé en santé et en sécurité du travail, Montreal, Canada;4. CONCAVE Research Centre, Concordia University, Montreal, Canada |
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| Abstract: | Apparent mass (AM) responses of the body seated with and without a back support on three different elastic seats (flat and contoured polyurethane foam (PUF) and air cushion) and a rigid seat were measured under three levels of vertical vibration (overall rms acceleration: 0.25, 0.50 and 0.75 m/s2) in the 0.5 to 20 Hz range. A pressure-sensing system was used to capture biodynamic force at the occupant-seat interface. The results revealed strong effects of visco-elastic and vibration transmissibility characteristics of seats on AM. The response magnitudes with the relatively stiff air seat were generally higher than those with the PUF seats except at low frequencies. The peak magnitude decreased when sitting condition was changed from no back support to a vertical support; the reduction however was more pronounced with the air seat. Further, a relatively higher frequency shift was evident with soft seat compared with stiff elastic seat with increasing excitation. |
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| Keywords: | biodynamic response cushion seats visco-elastic properties sitting conditions body mass effect elastic body-seat interface |
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