A composite guidance law is proposed for intercepting moving target while strictly satisfying the constraints on multiple No-Fly Zones (NFZs) distributed arbitrarily. The research has two major steps. In the first step, by considering only one NFZ, a guidance law is developed with three parts: Orientation Adjustment Scheme (OAS), Boundary-Constraint Handling Scheme (BCHS), and Proportional Navigation (PN). OAS determines the major flight direction by predicting the collision point of the missile and target. BCHS controls the missile to approach and then fly along the boundary of the NFZ smoothly so as to bypass the NFZ through a short path. PN is used to intercept the target in the endgame phase. In the second step, we use the multi-step decision process to set up a series of appropriate waypoints in order to avoid multiple NFZs. The superior performance of the proposed guidance law has been demonstrated by trajectory simulations.
This paper presents the design of a singular-perturbation-based optimal guidance with constraints on terminal flight-path angle and angle of attack. By modeling the flight-control system dynamics as a first-order system, the angle of attack is introduced into the performance index as a state variable. To solve the resulting high-order optimal guidance problem analytically, the posed optimal guidance problem is divided into two sub-problems by utilizing the singular perturbation method according to two time scales: range, altitude, and flight-path angle are the slow time-scale variables while the angle of attack is the fast time-scale variable. The outer solutions are the optimal control of the slow-scale subsystem. Thereafter, by applying the stretching transformation, the fast-scale subsystem establishes the relationships between the outer solutions and acceleration command. Then, the optimal command can be obtained by solving the fast-scale subsystem also using the optimal control theory. The proposed guidance can achieve a near-zero terminal acceleration as well as a small miss distance. The superior performance of the guidance is demonstrated by adequate trajectory simulations.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.