Performance Analysis of Suspension Seats under High Magnitude Vibration Excitations: II. Design Parameter Study

Abstract

The influences of suspension design parameters on the performance of three different suspension seats under high magnitude excitations were investigated using the generalized analytical model developed and validated in the first part of this work. The model was initially applied to study the influences of variations in the seated mass and suspension ride height on the response characteristics. Additional laboratory experiments were conducted and the measured data were used to demonstrate the validity of the generalized model under such variations in operating conditions for all three-suspension seats. The influences of variations in design parameters that could affect the performance under high magnitude excitations, namely suspension damping properties (low-velocity compression mode damping, damping asymmetry and high velocity damping) and properties of the elastic end-stops, on the performance measures are presented. Such influences are assessed in terms of seat effective amplitude transmissibility (SEAT), vibration dose value (VDV) ratio, peak accelerationof the seated mass and the peak force developed by the elastic end-stops. The results of the study suggest that suspension dampers with medium to high compression damping, higher rebound damping and higher high-speed damping would be desirable to realize enhanced performance under high magnitude excitations. Elastic end-stops with low stiffness are desirable to reduce the severity of the end-stop impacts.

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