Novel adaptive sliding mode guidance law against arbitrarily maneuvering target

A novel adaptive sliding mode guidance law is proposed in this article. The target is assumed to have an arbitrarily but upper bounded maneuvering acceleration which is considered as the system disturbances and uncertainties. The guidance law is consisted of three terms. The first one is a proportional navigation-type term. The second one is a term used for compensating the target maneuvering acceleration. And the last one is a term for controlling the convergence time of the line-of-sight angular rate. In this guidance law, the upper bound of the target acceleration is estimated by an adaptive estimator with a tunable updating law. Hence, the prior knowledge of the upper bound of the target acceleration is not essential for this guidance law. The novel adaptive sliding mode guidance law can guarantee the asymptotical convergence of the line-of-sight rate to zero or its neighborhood, or even the finite time convergence of the line-of-sight rate conditionally. Finally, the new theoretical findings are demonstrated by numerical simulations.