Impact time control guidance law considering seeker's field-of-view constraint without time-to-go information

Accurate time-to-go estimation with large heading angle error is difficult for homing guidance laws, especially for the impact time control. Considering this, a new cooperative guidance law which requires no time-to-go estimation is investigated. First, the impact time control problem is transformed to the look angle command tracking problem. The look angle command guarantees that the range-to-go error converges to zero asymptotically. Then the proposed guidance law considering the seeker's field-of-view constraint is derived using sliding mode control to track the desired look angle signal. Numerical simulations are performed to verify the effectiveness of the proposed guidance law for one-to-one and many-to-one engagement scenarios.