Nonlinear H/sub /spl infin// control of a missile's roll axis

This paper describes the application of a new method for generating the optimal H/sub /spl infin// controller for a nonlinear system. It is a three step approach: modeling (using the describing function approach), synthesis (using the H/sub /spl infin// loop shifting technique), and robustness analysis (using the labelling technique of simplicial algorithms). The method is demonstrated by designing an optimal H/sub /spl infin// controller for a cruise missile's roll axis. The actuator is a first order servo with deadband and command limiting.