Broadband random vibration test

In broadband random vibration testing the devices under test are excited with a stochastic, random shaped vibration in a wide frequency range (broadband). Broadband random vibration tests are usually characterized by the Power Spectral Density (PSD) over the frequency range.

Picture on the right: PSD plot of a broadband random vibration test

The broadband random excitation can also be superimposed with one or more harmonic, sinusoidal oscillations or one or more random vibration excitations. (See also sine on random test and random on random test.)

Road and rail vehicles are excited during operation by the unevenness of the ground (road, dirt track, off-road, rail track …) to random-shaped, stochastic vibrations in contrast to harmonic vibration excitation caused by combustion engines or electric drives, for example.

The vibration resistance of parts and components used in vehicle technology is therefore usually verified by means of a broadband random vibration test. Strength and duration of the vibration excitation depend on the mounting location (e.g. wheel, chassis, interior …) and the application (e.g. passenger car, commercial vehicle, locomotive …).