Analysis of the cornering stiffness uncertainty impact on the steering sensitivity of a two-axle automobile

Abstract

In order to provide a reliable estimate of the steering sensitivity at the early design stage it is necessary to know the impact of the ucertainty of the main parameters affecting this characteristic. These parameters include the tire cornering characteristics featuring a large degree of uncertainty. The objective of the research was to find the impact of the tire cornering characteristics variation on the steering sensitivity. The analysis was performed in a multi-body simulation program with the use of a spatial non-linear model of the automobile motion. The model takes into account the detailed kinematics of the suspension and steering linkages. Interaction of the tires with the road is described by an original semi-empirical model providing indepentent calibration of the tire longitudinal and lateral force characteristics in the contact patch. The reseach has demonstrated the degree of importance of considering the tire cornering stiffness variation during the steering sensitivity analysis.