A three-dimensional anti-saturation terminal guidance law with finite-time convergence

Abstract

In a practical terminal guidance process, missile acceleration may be saturated and the saturation can lead to degraded interception performance. This paper presents an anti-saturation guidance law with finite-time convergence for a three-dimensional maneuvering interception, using the theories of finite-time boundedness (FTB) and input-output finite-time stability (IO-FTS). With this law, the line-of-sight (LOS) angular rates converge in finite time while guaranteeing the missile accelerations do not exceed their physical limits. A sufficient condition for FTB and IO-FTS of a class of nonlinear systems is given, and is used to design the guidance law. Quasi-one-sided Lipschitz condition is employed to address the nonlinear term, and transforms the problem of ensuring the system FTB and IO-FTS simultaneously to that of solving a differential linear matrix inequality (DLMI). Simulation results verify the effectiveness of the new guidance law design.