Prescribed-Time Three-Dimensional Guidance for Maneuvering Targets with Field-of-View and Approach Angle Constraints

This paper presents a three-dimensional (3D) guidance law for homing missiles to intercept maneuvering targets, while ensuring a desired final approach angle and satisfying field-of-view (FOV) constraints. First, a line-of-sight (LOS) vector shaping method is introduced in the range domain. The desired approach angle and FOV constraint can be satisfied by precisely tracking a specified LOS vector profile. Then, a feedback guidance law is designed using a prescribed-time control technique for nullifying the LOS tracking errors. This guidance law employs an extended state observer to estimate and compensate for unknown target maneuvers, with a rigorous analysis conducted to ensure the stability of the entire system. Unlike existing studies, the proposed guidance law does not require linearization procedures and switching logic, which avoids discontinuous guidance command and facilitates practical implementation. Finally, extensive numerical simulations and comparison studies validate the effectiveness, robustness, and superiority of the proposed method.