TOWARDS THE STANDARDIZATION OF A TESTING METHOD FOR THE END-STOP IMPACTS OF SUSPENSION SEATS

✍ Scribed by X. Wu; M.J. Griffin

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 371 KB
• Volume: 192
• Category: Article
• ISSN: 0022-460X
• DOI: 10.1006/jsvi.1996.0189

✦ Synopsis

Standard tests of the vibration isolation efficiency of suspension seats currently use narrow-band input spectra representing the motions of specific vehicles. The motions used in these tests have near-Gaussian amplitude distributions, whereas vehicle motions include occasional extreme movements causing end-stop impacts of the seat suspension which increase the exposure of the seat occupant to vibration and shock. Tests have been conducted with various vibration magnitudes so as to quantify suspension seat isolation efficiency in terms of the ratios of the vibration dose values (VDVs) at the base of the seat, above the seat suspension and above the seat cushion. It is shown that the vibration response of a seat suspension occurs in five stages according to the magnitude of the input vibration, and that the cushion of a suspension seat may reduce the severity of severe end-stop impacts. The dynamic performance of a suspension seat when supporting a human subject and when supporting a sand bag is compared and the effect of mid-position adjustment is demonstrated. The form of an end-stop impact test which could supplement existing tests so as to evaluate the overall performance of suspension seats is discussed.