A Model of Vehicle Rollover Due to Side Impact Collision

Cars involved in side impact collisons have been known to roll over as a direct consequence of the side impact. A simple mathematical model is derived for collision rollover in central and eccentric side impacts. It is shown that the minimum impact velocity of the bullet vehicle or object necessary to cause rollover is dependent on the mass ratio of the struck vehicle to that of the bullet vehicle/object, the impact height, the tyre-road friction and on the eccentricity of the impact. The rollover velocity decreases as friction is increased. Consequently this form of rollover will, in general, most often occur on dry roads and at moderate to high impact velocities. The model is compared with data from staged motorcycle/car impacts and with two road accidents which resulted in rollover.