The Correlation of Objective Ride Measures to Subjective Jury Evaluations of Class 8 COE Vehicles

Fifty-six ride tests of class 8 COE vehicles were conducted. Linear correlation was investigated between subjective jury ratings and each of 12 objective ride measures that were calculated from vertical and longitudinal cab acceleration measurements. Ninety-five percent confidence band-widths and correlation coefficients were used to compare the correlation of each ride measure to the jury ratings.

The ride measure defined as: had the highest correlation, while the unweighted longitudinal rms acceleration correlated only slightly less well. Significantly lower correlation was obtained for the ride measures investigated containing longitudinal Absorbed Power or ISO weighted longitudinal rms acceleration. No significant degree of correlation was obtained for unweighted vertical rms acceleration, vertical Absorbed Power, or ISO weighted vertical rms acceleration.