A new anti-torpedo torpedo's guidance law based on variable structure control

For low hitting precision, bad robustness and high normal acceleration of traditional torpedo guidance law, the paper designed anti-torpedo torpedo(ATT) guidance law based on variable structure control. State equation of line of sight angle between ATT and target can be achieved from mathematical model of moving relation between ATT and target torpedo, and designed a variable structure controller to make line of sight angle constant that can be demonstrated by Lyapunov stability theory. The paper respectively constituted simulation model of ATT's intercepting trajectory based on traditional fixed early angle guidance law and guidance law based on variable structure control. Simulation results show that the guidance law based on variable structure control have good robusty for model parameters and jam, high hitting precision and stable smooth trajectory, therefore precede traditional fixed early angle guidance law.