A new method of determination of the velocity of a moving noisy machine by the analysis of a signal detected at a fixed point is proposed. In this system, it is assumed that the trajectory of the object is known beforehand and the special characteristics of a machine noise in the bispectral region are used so that a measuring system which does not suffer from any surrounding Gaussian noise is realized. The nonstationary change of the bispectral characteristics, along with the movement of the object, is detected from a set of short‐time bispectra in segmented intervals and the method of minimum mean‐square‐error fitting is applied to get reliable velocity. The principle, concrete construction, and experimental results are shown. The results show the superiority of the new method over conventional methods.