Terminal angle constrained optimal guidance law with finite time convergence

This paper mainly focuses on the terminal guidance problem for reentry vehicles with terminal angle constraints. An optimal finite time convergent guidance law is proposed which includes guidance equations in both dive plane and turn plane. Finite time control is introduced into the designing process along with optimal guidance law to make the line-of-sight (LOS) angular rate deviation converge to zero. The line-of-sight (LOS) angle converges to a desired angle in a finite time so that the closed-loop system has strong convergence performance and robustness. Compared with optimal guidance, sliding mode variable structure guidance and optimal guidance law with sliding-mode variable structure, simulation results show that the guidance law developed in this paper has strong robustness against disturbances.