The Effect of the Flexibility of Steering Systems on the Kinetic Characteristics of Automobiles

Abstract

In some tests of automobiles it is found that some cars show stronger understeering tendency than expected from their tyre characteritics. The main cause of this effect is considered to be the flexibility of their steering systems. According to the analysis in this paper the apparent cornering power of a front wheel is expressed as EK_f, where K_f is the actual cornering power of the wheel and E is a constant which is positive and smaller than the unity. This E depends on the conering power, self-aligning moment, caster angle and the flexibility of the steering system, being E=1 for a rigid steering system. Thus, the apparent cornering power of the front wheels decreases, if the steering system is flexible, and this apparent decrease in the cornering power increases the understeering tendency and the directional stability of the car.