Abstract
An approximate mathematical method is developed to evaluate integrated square error criteria of control systems. In this method the error response caused by a step reference input is approximated by a damped sinusoid. Close agreement is reported between the optimum gain adjustments given by the theory and the optimum points obtained by use of an analog computer. The theory is then modified and is applied to a control system which includes a gain switching, predicting a 20 to 30% improvement in performance, and is confirmed by an experiment on a pneumatic pressure process.
