Extremal aiming in problems with an unknown level of dynamic disturbance

The method of extremal aiming, well-known in the theory of differential games, is applied to problems in which the level of dynamic disturbance is not stipulated in advance. Problems with linear dynamics, a fixed termination time and a geometric constraint on the effective control are considered. The aim of the control is to bring the system into a specified terminal set at the instant of termination. A feedback control method is proposed which ensures successful completion if the disturbance does not exceed a certain critical level. Here, “weak” disturbance is countered by a “weak” effective control. A guarantee theorem is formulated and proved. An illustrative example is considered.