A three-dimensional terminal guidance law based on finite-time input-to-state stability

Finite-time input-to-state stability (ISS) guarantees that for any bounded input, the system state will be bounded in finite time. This property better satisfies the demands of the terminal guidance system f or target maneuver rejection performance and convergence rate. In this paper, using the finite-time ISS theory, a novel guidance law is proposed for the interception of three-dimensional maneuvering target. It is proved that, under this law, the line-of-sight (LOS) angular rates are finite-time ISS with respect to the bounded target maneuvers, and by adjusting the guidance parameters, can be stabilized to a small region containing the origin in finite time. Simulation results indicate that the designed guidance law can achieve tracking and intercepting the maneuvering target in finite time, and has strong rejection performance of disturbance and fast convergence rate.