Continuous finite-time stabilization guidance law for terminal impact angle constrained flight trajectory

Aiming at the demands for terminal impact angle constraint and shaped terminal trajectory as straight as possible for some guided weapons, a continuous finite-time stabilization guidance law with terminal impact angle constrained trajectory is designed using the finite-time control technique. This guidance law ensures that the line-of-sight rate converges to zero and the line-of-sight angle converges to the desired angle within a finite time. This law is analyzed by utilizing the finite-time stabilization homogeneous theory of nonlinear control systems, thus confirming the global finite-time convergence of the line-of-sight rate and angle in the closed guidance system. Based on the finite-time Lyapunov stability theory, the expression of convergence time is yielded for the closed guidance system. In simulations of an application example, the guidance performance of the proposed law is compared with optimal guidance law, and the guidance effect of the proposed design on different operation tasks is verified. Simulation results have demonstrated that the proposed guidance law is effective and robust.