Dynamic characteristics of a compliant seat coupled with the human body and a manikin during the exposure to the whole-body vibration: effect of the polyurethane foam, the track position and the measurement location

Zhang, Xiaolu; Lin, Sen; Song, Xichen; Liu, Chi; Qiu, Yi

doi:10.37190/abb-02452-2024-02

Abstract

Transmissibility is used to assess dynamic responses of the occupant-seat system, and most studies have exclusively assessed the transmissibility from the floor to the cushion or the backrest surface with the human body. In this investigation, the vertical vibration transmitted from the floor to six specific locations both on the seat surface and the frame when the seat was fixed on three positions on the track was examined utilizing an SAE J826 manikin and 12 male adults (0.25 to 20 Hz) for a duration of 120 seconds at three vibration amplitudes. The transmissibility from the floor to the headrest frame, the cushion surface, the headrest surface, the seat back frame, and the seat back surface all exhibited a principal peak frequency within 4–5 Hz. With the exception of the cushion frame, the principal peak frequency and the peak transmissibility in transmissibilities to all positions decreased with increasing vibration amplitude, indicating the non-linearity within the occupant-seat system. It was also found modifying seat track positions minimally affected the seat transmissibility to either the surface or the frame of the seat. Polyurethane foam amplified vibration at peak frequency, simultaneously enhancing static sitting comfort and reducing the vertical vibration transmission above peak frequency.

References

Adam S.A., Jalil N.A.A., Rezali K.A., Ng Y.G., The effect of posture and vibration magnitude on the vertical vibration transmissibility of tractor suspension system, International Journal of Industrial Ergonomics, 2020, 80, 103014, DOI: 10.1016/j.ergon.2020.103014.
Search in Google Scholar Back to article
Arnold J., Griffin M.J., Equivalent comfort contours for fore-and-aft, lateral, and vertical whole-body vibration in the frequency range 1.0 to 10Hz, Ergonomics, 2018, 61, 1545–1559, DOI: 10.1080/00140139.2018.1517900.
Search in Google Scholar Back to article
Barbeau R., Weisser T., Dupuis R., Aubry É., Baudu S., Assessment of the impact of sub-components on the dynamic response of a coupled human body/automotive seat system, Journal of Sound and Vibration, 2019, 459, 114846, DOI: 10.1016/j.jsv.2019.07.012.
Search in Google Scholar Back to article
Bang J.H., Lee C.A., Kim H.Y., Kim H.J., Choi K.Y., Optimization of the static properties of seat foam to improve the seating comfort. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 2017, 231, 1945–1960, DOI: 10.1177/0954407016688782.
Search in Google Scholar Back to article
Dewangan K.N., Rakheja S., Marcotte P., Shahmir A., Effects of elastic seats on seated body apparent mass responses to vertical whole body vibration, Ergonomics, 2013, 58, 1175–1190, DOI: 10.1080/00140139.2015.1052852.
Search in Google Scholar Back to article
Deboli R., Calvo A., Preti C., Whole-body vibration: Measurement of horizontal and vertical transmissibility of an agricultural tractor seat, International Journal of Industrial Ergonomics, 2017, 58, 69–78, DOI: 10.1016/j.ergon.2017.02.002.
Search in Google Scholar Back to article
Gao K., Zhang Z., Lu H., Xu Z., He Y., Finite element modelling and biodynamic response prediction of the seated human body exposed to whole-body vibration, Ergonomics, 2023, Jan. 18, 1–4.
Search in Google Scholar Back to article
Kim E., Fard M., Kato K., A seated human model for predicting the coupled human-seat transmissibility exposed to fore-aft whole-body vibration, Applied Ergonomics, 2020, 84, 102929, DOI: 10.1016/j.apergo.2019.102929.
Search in Google Scholar Back to article
Kim S.G., Ko C., Kim D.H., Song Y.E., Kang T.U., Ahn S., Lim D., Kim H.S., Development of a shear force measurement dummy for seat comfort, Plos One, 2017, 12, e187918, DOI: 10.1371/journal.pone.0187918.
Search in Google Scholar Back to article
Kolich M., Essenmacher S.D., McEvoy J.T., Automotive seating: the effect of foam physical properties on occupied vertical vibration transmissibility, Journal of Sound and Vibration, 2005, 281, 409–416, DOI: 10.1016/j.jsv.2004.03.058.
Search in Google Scholar Back to article
Liu C., Qiu Y., Non-linearity in the localised apparent masses of the seated human body exposed to vertical vibration, Mechanical Systems and Signal Processing, 2020, 135, 106394, DOI: 10.1016/j.ymssp.2019.106394.
Search in Google Scholar Back to article
Lin J., Li M., Lin Z., Wang J., Meng X., Zhang J., Equivalent magnitude-dependent discomfort under vertical vibration up to 100 Hz, Ergonomics, 2023, Oct. 3, 66 (10), 1415–1423.
Search in Google Scholar Back to article
Liu C., Qiu Y., Mechanism associated with the effect of backrest inclination on biodynamic responses of the human body sitting on a rigid seat exposed to vertical vibration [J], Journal of Sound and Vibration, 2021, 510, 116299, DOI: 10.1016/j.jsv.2021.116299.
Search in Google Scholar Back to article
Lin Z., Zhang J., Li M., Zhuang Y., Liu C., Lin J., Biodynamic response of seated human body to roll vibration: Effect of armrest support, Journal of Sound and Vibration, 2022, Jul. 7, 529, 116939.
Search in Google Scholar Back to article
Lin Z., Zhang J., Li M., Wang J., Zhang X., Lin J., Torque response of seated human body to sinusoidal lateral and roll dual-axis vibration, Ergonomics, 2023, Jul. 3, 66 (7), 916–926.
Search in Google Scholar Back to article
Mandapuram S., Rakheja S., Marcotte P., Boileau P., Analyses of biodynamic responses of seated occupants to uncorrelated fore-aft and vertical whole-body vibration, Journal of Sound and Vibration, 2011, 330, 4064–4079, DOI: 10.1016/j.jsv.2011.04.003.
Search in Google Scholar Back to article
Nawayseh N., Effect of the seating condition on the transmission of vibration through the seat pan and seat back, International Journal of Industrial Ergonomics, 2015, 45, 82–90, DOI: 10.1016/j.ergon.2014.12.005.
Search in Google Scholar Back to article
Patelli G., Griffin M.J., Effects of seating on the discomfort caused by mechanical shocks: Measurement and prediction of SEAT values, Applied Ergonomics, 2019, 74, 134–144, DOI: 10.1016/j.apergo.2018.08.003.
Search in Google Scholar Back to article
Tufano S., Griffin M.J., Non-linearity in the vertical transmissibility of seating: the role of the human body apparent mass and seat dynamic stiffness, Vehicle System Dynamics, 2013, 51 (1), 122–138, DOI: 10.1080/00423114.2012.715652.
Search in Google Scholar Back to article
Toward M.G.R., Griffin M.J., The transmission of vertical vibration through seats: Influence of the characteristics of the human body, Journal of Sound and Vibration, 2011, 330, 6526–6543, DOI: 10.1016/j.jsv.2011.07.033.
Search in Google Scholar Back to article
Vink P., Lips D., Sensitivity of the human back and buttocks: The missing link in comfort seat design, Applied Ergonomics, 2017, 58, 287–292, DOI: 10.1016/j.apergo.2016.07.004.
Search in Google Scholar Back to article
Wang H., Ge Q., Zeng D., Zhang Z., Chen J., Human-Induced Vibration Serviceability: From Dynamic Load Measurement towards the Performance-Based Structural Design, Buildings, 2023, Aug. 2, 13 (8), 1977.
Search in Google Scholar Back to article
Wu J., Qiu Y., Zhou H., Biodynamic response of seated human body to vertical and added lateral and roll vibrations, Ergonomics, 2022, 65, 546–560, DOI: 10.1080/00140139. 2021.1967461.
Search in Google Scholar Back to article
Yao J., Fard M., Davy J.L., Kato K., The prediction of vehicle vibration transmitted to the occupant using a modular transfer matrix, Journal of Vibration and Control, 2022, 28, 1698–1711, DOI: 10.1177/1077546321997593.
Search in Google Scholar Back to article
Zhang X., Zhang Q., Li Y., Liu C., Qiu Y., Effect of the thickness of polyurethane foams at the seat pan and the seat back on fore-and-aft in-line and vertical cross-axis seat transmissibility when sitting with various contact conditions of seat back during fore-and-aft vibration, Applied Ergonomics, 2021, 93, 103354, DOI: 10.1016/j.apergo.2021.103354.
Search in Google Scholar Back to article
Zhang Z., Jin K., Li F., Lu C., Chai G., Ye D., Effects of adjustment devices on the fore-and-aft mode of an automobile seat system: headrest, height adjuster, recliner and track slide, Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 2016, 230, 1140–1152, DOI: 10.1177/0954407015602823.
Search in Google Scholar Back to article
Zhang X., Yu P., Li Y. et al., Dynamic interaction between the human body and the seat during vertical vibration: effect of inclination of the seat pan and the backrest on seat transmissibilities [ J], Ergonomics, 2022, 65 (5), 691–703, DOI: 10.1080/00140139.2021.1983028.
Search in Google Scholar Back to article
Zhang X., Qiu Y., Griffin M.J., Transmission of vertical vibration through a seat: Effect of thickness of foam cushions at the seat pan and the backrest [J]. International Journal of Industrial Ergonomics, 2015, 48, 36–45, DOI: 10.1016/j.apergo. 2018.08.003.
Search in Google Scholar Back to article

Dynamic characteristics of a compliant seat coupled with the human body and a manikin during the exposure to the whole-body vibration: effect of the polyurethane foam, the track position and the measurement location

Abstract

Paradigm

My account