Terminal angle constrained time-varying sliding mode guidance law with autopilot dynamics and input saturation

To intercept the maneuvering target at a desired terminal angle, this paper presents a time-varying sliding mode guidance law with consideration of the second-order autopilot dynamics and input saturation. To achieve the finite-time interception and satisfactory overload characteristics, a time-varying sliding mode guidance law is developed, which enables the line-of-sight (LOS) angle error to converge into a small neighborhood of the origin at the interception time. An auxiliary system is constructed to reduce the adverse effect generated from the input saturation. Moreover, with the aid of extended state observers, the proposed guidance law requires no information on the target acceleration and the acceleration derivative of the interceptor. The performance of this guidance law is verified via the numerical simulations.