Abstract:

Based on the infinite impulse response digital filter theory,a frequency weighting filter was designed according to the frequency weighting factors in the standard ISO2631-1:1997 (E).The weighted acceleration data in the timedomain and the crest factor of vibration were obtained by the filtering of the time-domain acceleration signal using the fuequency weighted digital filter. The analyses showed that the crest factor of the vibration in all axes is lower than 9 under random vibration, the basic evaluation method can be used to evaluate the vehicle ride comfort. Under the conditions of occasional shock and transient vibration, the crest factors in the vertical direction of the seat, the seat rail and the under-seat floor will be higher than 9, and the additional evaluation method should be used. The results showed that the vehicle ride comfort weighted evaluation in time-domain can be achieved by the frequency weighted digital filtering, it can compensate the inadequacy of the traditional weighted evaluation method in frequency domain in being unable to get the crest factor, and enhance the accuracy of vehicle ride comfort evaluation.

Key words: vehicle engineering, frequency weighted filter, crest factor, digital filter, ride comfort, evaluation