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This article proposes barrier Lyapunov function-based guidance strategies to achieve target interception, by a seeker-equipped interceptor having a limited field-of-view (FOV), at a prespecified impact time. A novel approach to respect the FOV constraint, using the conditions on time-to-go of the engagement, is first proposed. Guidance commands are then derived to steer the course of the interceptor in a way so as to adhere to the necessary conditions. Guidance strategy is first derived for 3-D engagements, and then, the same for planar scenarios is presented as a special case. The set of achievable impact times for given initial conditions, while satisfying FOV constraints, is first obtained, and then, a way to expand the achievable range of impact time is suggested using a two-stage approach. The behavior of lead angle is analyzed, and it is shown that guidance commands remain nonsingular and converge to zero near interception. Simulations are shown to validate the efficacy of proposed methods for various initial engagement geometries. [ABSTRACT FROM AUTHOR]

This article proposes a guidance strategy that enables the interceptor to control its impact time against stationary targets, while also meeting the field-of-view (FOV) constraints of the on-board seeker. The guidance strategy, so designed, always keeps the target within its FOV using its seeker. A barrier Lyapunov function is used to meet the FOV constraints, and an approximate expression for the interceptor's lead angle is obtained analytically. This facilitates the computation, as well as control, of impact time. The proposed guidance consists of two stages, with the former stage being deviated pursuit, while during the latter stage, the deviation angle or lead angle decreases to zero. This, in turn, ensures a zero terminal lateral acceleration. Furthermore, through a cooperative selection of tuning parameters, simultaneous interception of the target by multiple interceptors (also called salvo) can be achieved. Simulations, that are run for different engagement scenarios and with varying tuning parameters, vindicate the efficacy of the proposed strategy. [ABSTRACT FROM AUTHOR]