We outline two example applications of optimal control methodologies to aid in the design of control systems. The first method uses CONSOLE, a computer-aided design program based on feasible direction and multicriterion optimization, for controller parameter selection. The second method, based on linear quadratic regulator theory, selects a controller structure where the parameters are selected to minimize a performance function. Each of these methods is demonstrated using a realistic example for Grumman Aerospace Corporation. The CONSOLE method is used for a pitch control design for the X-29, a forward-swept wing aircraft, while the linear-quadratic- gaussian/loop transfer recovery method is used for a pitch control design for the F- 14.

We show that the designs from these methods are at least comparable to ones done with other methods. In fact, the LQG/LTR design method leads to a stable robust design. Therefore, these design tools would be useful additions to a control designer's toolbox.