Considerations in servomechanism design

SERVOMECHANISMS include many familiar regulator systems. The simple float valve controlling water level in a tank and the voltage regulator in reality are servomechanisms. The war has brought about many important new applications including: holding airplanes and ships on predetermined courses; stabilizing and rotating guns; producing exact duplicates of intricate patterns and dies; indicating flap or landing-gear position; and a multitude of others. Probably the most common servomechanism system is that which matches the position of a high-torque shaft to that of a low-torque shaft. This will be referred to as an angular-position servomechanism. By means of this servomechanism the high power required to operate a gun turret can be controlled so that the gun accurately matches the position of a low-power hand-operated sight. Whether the operating power is electric, hydraulic, or a combination of these or other types of power, the analysis to follow provides a basis for obtaining servomechanism performance in terms of basic design parameters.