Nonlinear Impact Time Guidance with Constrained Field-of-View

In this paper, we propose a guidance strategy that enables the interceptor to control the time of interception against stationary targets, while also respecting the field-of-view (FOV) constraints of the seeker. Such a guidance strategy always keeps the target within its field-of-view, using its seeker. Guidance command is derived using a barrier Lyapunov function, and an expression for lead angle of interceptor is obtained analytically, which further facilitates the computation and control of the impact time. The guidance comprises two stages, one of which is deviated pure pursuit, while during the latter stage, the deviation angle or lead angle decreases to zero thereby ensuring zero terminal lateral acceleration. Simulations across different engagement scenarios and tuning parameters vindicate the effectiveness of the proposed strategy.