Fixed-order dynamic compensation for linear systems with actuator amplitude and rate saturation constraints

We develop fixed-order (i.e., full- and reduced-order) controllers for linear systems with actuator amplitude and rate saturation constraints. The problem is formulated as a multiobjective problem involving a convex combination of an L₁ norm and the H₂ norm to capture actuator saturation constraints and closed-loop system performance in the face of exogenous white noise disturbances. The L₁ convolution operator norm considered is induced by bounded amplitude persistent L_∞ disturbances and L_∞ performance variables involving the actuator amplitude and rate signals. Hence, the peak point-wise-in-time actuator amplitude and actuator rate excursion is guaranteed to be less than the product of the L₁ convolution operator norm and the L_∞ disturbance amplitude bound. Application of the proposed framework to the design of multivariable saturation controllers for the control of a bank-to-turn missile is demonstrated