Design of the robust guidance law with terminal angle constraint

According to the requirements of some types of missiles which attack target with specified angle at the terminal point,a guidance law with angular constraint is designed.System perturbation and target acceleration are regarded as an exogenous disturbance,then the guidance law which meets the performance of L_2 gain is achieved by Lyapunov method.Simulation results show that both the precision and impact angle are met well even when target maneuvers with a large acceleration.And the guidance law has no use for any target information and shows a good robustness.