Samenvatting
Results of tests with 6 type of car show that above a certain speed, about 30 km/h, a discontinuity will act as an impulse to the car's suspension system, since the time interval between the passage of the front and rear wheel is short. As a result at speeds above 30 km/h two resonant modes are exited-a "body heave" at about 1.75 Hz, and "wheel-hop" at 10-15 Hz. Below this speed the shape of the discontinuity becomes important.