Sliding mode guidance law design based on terminal angle constraint

For the guidance of attacking target on the ground,a new robust nonlinear sliding mode guidance law with terminal angle constraint is proposed.The mathematic model was built according to nonlinear relationship between missile and target whose acceleration as disturbance was introduced.Based on variable structure control theory and the method of zeroing the rate of line-of-sight angle between missile and target,a suitable nonlinear terminal sliding mode with ideal terminal angle is chosen instead of conventional sliding mode,a new nonlinear sliding mode guidance law is designed,and the reachability and stability of sliding mode is strictly proved by Lyapunov stability theory to satisfy the condition of terminal angle.Finally,the digital simulation results show that the sliding mode guidance law is adopted to attack the ground target,both the impact angle and guidance precision are met in the case of no any target information.