Guidance law with finite time convergence considering thrust constraint and dynamics characteristic

A guidance law of nonsingular terminal sliding mode with robustness is proposed for the guidance considering thrust constraint and dynamic daelay of the engine, and the condition of finite time convergence is also given. Firstly, the mathematical model of relative movement considering the first order dynamic delay is set up according to the planar relative motion of the missile and the target. Secondly, based on the theory of finite time, the condition and properties of finite time convergence of the guidance law under the thrust constraint is proposed. It is expanded to consider the dynamics, and the nonsingular terminal guidance law is proposed. Finally, the boundary layer function is employed to eliminate the chattering instead of the sign function. Simulation results show that the guidance law achieves higher guidance precision and robustness to the high speed maneuvering target, also the condition and properties of finite time convergence are verified.