Integrated guidance-control system for beam-riding guidance missiles based on second order sliding mode control

An Integrated Cuidance-Control (IGC) law is proposed, using the super-twisting second order Sliding Mode Control (SMC) method, for the beam-riding guidance missiles. The fourth order state equation for integrated guidance and control loop was formulated taking into consideration the target uncertainties and control loop dynamics. Based on the transition matrix of the state equation, the zero-effort miss (ZEM) was redefined without calculating the time-to-go. By choosing the ZEM as a single sliding surface, the integrated super-twisting second order sliding mode guidance law was obtained. Simulation results show that ZEM and guidance range error could converge to zero in a finite time almost without any overshoot. The advantages of the integrated guidance are also validated by comparing with the conventional guidance without considering control loop.