Some saturation phenomena in servomechanisms with emphasis on the tachometer stabilized system

This paper describes some experimentally observed servomechanism saturation phenomena and introduces principles and techniques useful in the explanation of these phenomena and in the analysis of saturating servomechanisms. Typical tachometer servomechanism frequency responses with varying input magnitude, including the ¿jump¿ resonance phenomenon, are described. The simple principle ¿that the effect of saturation is to lower the average gain value of the path in which saturation takes place¿ is applied to the linear transfer function plot to explain the frequency responses. An analytical graphical technique for obtaining the steady-state frequency response of a saturating servomechanism is presented and is used to explain the phenomenon of jump resonance. Techniques for obtaining the transient response of simple saturating servomechanisms are also presented.