Steering wheel being the most used tactile point in a vehicle, its feel and response is an important factor based on which the vehicle quality is judged. Engineering the right feel and response into the system requires knowledge of the objective parameters that relate to the driver perception. Extensive correlation work has been done in the past pertaining to passenger cars, but the driver requirements for commercial vehicles vary significantly.
Often it becomes difficult to match the right parameters to the steering feel experienced by the drivers, since most of the standard ISO weave test units used to describe them are of zero or first order parameters. Analyzing the second order parameters gave a better method to reason driver related feel. Also, each subjective attribute was fragmented into sub-attributes to identify the reason for such a rating resulting in the identification of the major subjective parameters affecting driver ratings. In this paper, the relationship between the feel experienced by professional truck drivers and vehicle dynamics experts alike and how individual objective parameters can be related to them are examined.
Vehicles of similar category with varying steering system components were selected for the study. A detailed subjective assessment followed by physical testing was performed to compare the expressed steering feel to measured metrics. The results obtained from the comparison provides a method to evaluate steering feel through objective parameters and to identify the various factors drivers are exposed to when rating steering feel. A profound understanding was achieved with respect to the effect of steering system on-center and off-center related feel and response among other parameters.