A novel robust proportional navigation guidance law design for missile considering autopilot dynamic

Abstract

In this paper, a novel robust proportional navigation guidance (RPNG) law is derived for missiles by integrating sliding mode control theory and proportional navigation guidance law in order to achieve robustness against target accelerations. A first-order autopilot dynamic is taken into account in the state space equations of the nonlinear missile-target engagement dynamic. The robustness of the designed guidance law against external disturbances is proved by the second method of Lyapunov. Some coefficients that appear in the proposed RPNG law are obtained using the genetic algorithm. Performance of the new designed guidance law is compared with the well known augmented proportional navigation guidance (APNG) law. Considering different types of target accelerations and several scenarios, numerical simulations are presented. Simulation results show that the proposed guidance law has much better robustness in comparison with the APNG law. Moreover, it is simple and easy to implement from the point of view of practical applications.