Analyzing the influences of bus driver seat’s suspension system on driver’s comfort level and stability

Abstract

The influences of the seat suspension on the comfort level, and stability of the bus driver are analyzed using a three-degree-of-freedom (3DOF) quarter-vehicle model. The influences are analyzed through the effects of seat suspension damping ratio ξ se on driver frequency weighted acceleration a w (m/s2) (comfort level) according to ISO 2631:1-1997 standard, the ratio of driver acceleration and gravitational acceleration a/ g (vertical stability). With random excitation according to ISO 8608, considering the same vehicle speed value v (km/h) (in the region of 10 – 20 (km/h)), the decrease of ξ se increases the a w value, this result leads to the reduction of comfort level; Considering the same ξ se value, a w value decreases as increasing v value. With transient excitation according to IRC 99 – 1988, considering the same v value, the smaller ξ se creates the larger a/ g value; Considering the same ξ se, the value of a/ g increases and reaches the extreme in the vehicle speed range 20 – 30 (km/h), outside this speed range the value of a/ g decrease.