Augmented proportional navigation guidance using subspace-stabilization

The paper is concerned with the application of subspace-stabilization control theory to the missile guidance problem. In particular, the system error-state vector is stabilized to a certain subspace of the error state-space such that zero predicted miss-distance is achieved. The proposed control technique is related to the classical proportional navigation and augmented proportional navigation guidance laws, and accommodates in real-time uncertain effects in the plant model, as well as uncertain target motion with respect to the chosen line-of-sight/collision-line. Numerical simulation results are presented to illustrate the validity of proposed design. The guidance concept is extended, similar to optimum proportional navigation, to take into account the missile's response-time, and to reduce the required maneuver advantage.