Efficient nonlinear reference governor algorithms for constrained tracking control systems

Discrete-time tracking control systems that are subject to high amplitude dynamic reference signals, hard state and control constraints, and open-loop unstable plants are addressed. A nonlinear dual-loop controller architecture is used to constrain the controlled process state vector to a positively invariant set. Saturation avoidance and guaranteed BIBO stability are achieved. Online computational burden is reduced by using reference governor algorithms based on polyhedral subsets of the controlled process maximal statically admissible set. Practical considerations are provided for selecting an appropriate subset, and the methodology is illustrated with a fourth-order flight control problem