In the design of the image guided bomb, the frame angle varies in a limited range in order to avoid hitting the frame of the miniaturization seeker. Therefore the guidance with a limited frame angle range of the image guided aircraft should be studied. The frame angle increases with the decrease of the line-of-sight distance in the three-point guidance, but it is the other way round using the proportional guidance. Therefore, the maximum frame angle is reached when changing the guidance law from the three-point guidance to the proportional guidance. In this paper, a modified proportional navigation is put forward to decrease the frame angle when following a curve escaping target. The frame angle can thus be limited in a small range according to the simulation results.

frame angle  /  target maneuver  /  guidance law