The kinematics of universal joints used in drive shafts also give rise to vibrations. In the description of the vibrational behavior of systems consisting of universal joints (e.g. cardan shaft), the transfer characteristics of universal joints play an important role. When deflected through an angle (buckling angle α), the universal joint does not transfer rotational motion uniformly. At a constant input speed ω1 the output speed ω2 fluctuates periodically (see Figure). The parameter-excited vibrations produced as a consequence lead to resonance's. Axle Suspension
Not only unevenness in road surfaces, but also imbalances in rotating parts (tires, rim, brake disk) or high concentric running tolerances of the tires excite the drive train to uncontrolled vibrations during the compression of the axle suspension.