Design of Guidance Law for Anti-torpedo Torpedo Based on Variable Structure Control

Aiming at the low hitting precision and big normal overload of traditional torpedo guidance law, a guidance law for an anti-torpedo torpedo(ATT) based on variable structure control is designed. This ATT guidance law is on the basis of a mathematical model of movement relation between an ATT and a target torpedo. A variable structure control model is established taking course angle as control parameter and angular speed of line-of-sight as sliding mode surface. The proposed model needs a few parameters, and the parameters can be self-adaptively adjusted. Theoretical analysis and simulation show that the ATT guidance law is very robust for model parameters and environmental interference, and can gain high hitting precision and stable trajectory.