Evaluation of seatback vibration based on ISO 2631-1 (1997) standard method: The influence of vehicle seat structural resonance

Although much research has been done in developing the current ISO 2631-1 (1997) standard method for assessment seat vibration comfort, little consideration has been given to the influence of vehicle seat structural dynamics on comfort assessment. Previous research has shown that there are inconsistencies between standard methods and subjective evaluation of comfort at around vehicle seat twisting resonant frequencies. This study reports the frequency-weighted r.m.s. accelerations in , and axes and the total vibration (point vibration total value) at five locations on seatback surface at around vehicle seat twisting resonant frequencies. The results show that the vibration measured at the centre of seatback surface, suggested by current ISO 2631-1 (1997), at around twisting resonant frequencies was the least for all tested vehicle seats. The greatest point vibration total value on the seatback surface varies among vehicle seats. The variations in vibration measured at different locations on seatback surface at around twisting resonant frequencies were sufficiently great that might affect the comfort assessment of vehicle seat.Practitioner Summary: The influence of vehicle seat structural dynamics has not been considered in current ISO 2631-1 (1997). The results of this study show that the vibration measures on seatback surface at around vehicle seat twisting resonant frequency depends on vehicle seats and dominate at the top or the bottom of seatback but not at the centre.

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