Rolling over an obstacle

Experimental results are presented on the rolling of a steel ball over a small step. The experiment was designed to simulate the effects of surface roughness on rolling motion, where collisions between asperities on the ball and the rolling surface act to enhance the coefficient of rolling friction. In the present experiment, the ball was launched as a projectile when colliding with the step, with a consequent increase in vertical speed and a decrease in horizontal speed. Results are presented for four different diameter balls and four different steps, at incident rolling speeds between 0.3 and 1.2 m s−1.