The error power spectrum as a technique for assessing the performance of the human operator in a simple task

The measurement of performance of a human operator in a closed loop control system is considered; it is suggested that the power spectrum of the fluctuations of his tracking error (or error spectral density curve) gives a useful picture of performance and the equipment and technique for producing such a curve is described briefly.

As an example of the technique the power spectra obtained on several subjects performing a simple task with a pressure joystick are given and the implications of the shape of the curve are discussed.