Objective Evaluation of Subjective Driving Impressions

In the development of passenger car driving behaviour much subjective testing is involved. Although many car manufacturers have developed objective test methods and have corresponding analyses, objective parameters which correlate one to one with the subjective rating in the international rating scale (1-very bad .... 10-excellent) are not available. FEV has developed objective parameters for two main interest items, steering response and secondary ride comfort. These parameters consider different analyses and correlate very well with the subjective ranking of the test drivers. To achieve this, an investigation was put through with more than 10 different vehicles, ranging from sportscar to SUV but focused on modern mainstream European cars. The cars were subjectively assessed by more than 20 experts and laypersons and a large number of measurements has been taken. The two parameters are developed based on a statistical regression analysis but a relation between separate sub-properties is maintained. The result is a simple measurement procedure that gives recognisable parameters and combines these to give an absolute rating for any car in the market. The parameters deliver the reason for a good or bad behaviour as well, so that optimisation measures can be focused on the main cause. This article deals with development of the objective parameters.