Stochastic fast smooth second-order sliding modes terminal guidance law design

Aiming at handling the track imprecision caused by inertial lag, model uncertainties and atmospheric environment disturbances, as well as stochastic noises, a terminal guidance law based on stochastic fast smooth second-order sliding modes control theory is proposed. This paper considers targets performing evasive maneuvers and develops a high-order sliding mode observer. A concept of finite-time mean-square practical convergence, considering the non-equilibrium additive noise of the guidance system, is presented. And according to this concept, the finite-time convergent guidance law is deduced. The feasibility of the new guidance law is exemplified through computer simulations and the guidance performance is compared with augmented proportional navigation guidance law, sliding mode guidance law and nonsingular terminal sliding mode guidance law.