Three-Dimensional Nonlinear Impact Time Guidance Considering Field-of-View Constraints

This letter proposes a three-dimensional nonlinear guidance strategy that guarantees the interception of stationary targets at the desired impact time while accounting for the onboard seeker’s field-of-view constraints. The proposed approach for designing guidance law does not require a time-to-go estimation. It utilizes range-to-go, free from time-to-go approximations, allowing the interceptor to control the time of interception. Guidance command, derived using prescribed constraint function and sliding mode control considering coupled and nonlinear engagement kinematics, continuously maintains the target within its field-of-view bound and achieves guidance objectives. The proposed guidance strategy performs effectively, even for large deviations from the collision course, where pitch and yaw channels may be strongly coupled. Finally, the proposed guidance scheme is shown to be superior to existing strategies through numerical simulations.