Machines to perform tests on components of rubber or rubber-metal were specifically designed to detect and compare the static and dynamic characteristics (stiffness and damping) of the component under test.

When the component is put in real use conditions, applying a static preload or imposing a deflection, two types of tests are performed in sequence:

• from the execution of a test at low speed (static test), it detects the static diagram and from this we obtain the value of the static rigidity of the component conditions of use.
• Through dynamic tests are detected, maintaining a constant amplitude of the sinusoidal excitation by varying the frequency, the dynamic stiffness and the phase shift angle between displacement and load, which identifies the damping value of the testing component.

The detections are made using appropriate position transducers, of acceleration and load.

The operation frequency fields of this type of machines are essentially two:

• 4 – 25/40 Hz with amplitudes of excitation ± 0.05 / 2.5 mm and
• 25-500 Hz with amplitudes of excitation ± 0.025 /0.2 mm.

For special requirements, such as checking a motor support in resonance conditions, can be installed one inertial mass with variable weights which is applied a positive displacement transducer to allow detection of the excitation and the response of the resonant system consisting the inertial mass and the component under test. Other static machines for fatigue tests for vibration-damping can be made with two linear actuators or a linear actuator, and a torsional actuator so as to permit the biaxial testing (e.g. application of radial, axial or torsional load on a bushing).