Guidance law design based on non-smooth control

Abstract

The guidance law design for the missile–target interception problem in the presence of system uncertainty is investigated in this paper. To improve the disturbance rejection property, two kinds of non-smooth guidance laws based on a finite-time control technique are developed. The first is a high-gain finite-time guidance law, which can be derived by assuming that the system uncertainty is bounded by a constant. The second one is a composite guidance law including a disturbance observer and a finite-time state feedback, where the disturbance observer is introduced to estimate the system uncertainty and the finite-time state feedback is to stabilize the guidance system. Under both of the proposed guidance laws, it can be proved that the line-of-sight angle rate will converge to the origin or a small region of the origin in a finite time. Simulation comparisons show the effectiveness of the proposed method.