This paper describes the non-linear elements and circuit techniques used with the California Institute of Technology electric analog computer. Their application to nonlinear mechanical vibratory systems and nonlinear servomotors is discussed in detail. These techniques have been found to be generally suitable for representing single valued nonlinear functions of a dependent variable. Nonlinear springs, spring loaded backlash, and nonlinear damping factors can be readily simulated as well as saturation effects and other single valued non-linearities in servomotors. Methods of analysis are illustrated for several typical problems including a nonlinear rotating mechanical system and an autopilot employing a solenoid-operated rate and position limited hydraulic motor. Numerous servos of this type have now been studied and correlation of computer solutions with actual servo test data have shown in every case that the mathematical equations presented here accurately describe this type of motor
