Abstract: In the calculations of the tonsional vibration problems of the shaft system with planetary gear train, the single mass method which is generally used makes the dynamic process inside the gear train into the simplified static one. As the results, it brings some errors that are not safety; and it could only solve the shaft problems. In this paper, the experiments are done for the purpose to prove the reliability of the fictitious co-planar model proposed by authors for the calculations of the torsional vibration of the shafting with planetary gear. In the case, the influence of the planetary gearing to the shaft system can be studied, meantime the rotary states of the elements inside the planetary gear train, at the excitation of torsional vibrations, can be observed.

Key words: 扭振, 行星齿轮传动, 轴系