Control system of the fatigue stand for material tests under combined bending with torsion loading and experimental results

The paper presents the control system of the fatigue test stand MZGS-200PL. Electric signals from the strain gauge Wheatstone bridges were processed with spectrum analyzer and the computer. In the computer, the signals were registered on the hard disk. The paper presents characteristics signals loading, power spectral density, autocorrelations and cross-correlation. The circular smooth specimens were tested. As compared with hydraulic machines for fatigue tests, the presented machine is reliable and simple, it works quietly, it allows to save energy, it is small and cheap. The test stand MZGS-200PL allows to perform tests under cyclic proportional, non-proportional and random bending with torsion, as well as tests under pure bending and pure torsion.