Varying Speed Cooperative Differential Game Guidance Laws With Intercept Angle Constraints

For intercepting modern highly maneuvering targets, considering the velocity variation of adversaries, a varying speed cooperative differential games guidance method is proposed, which can enable multiple air-to-air missiles to intercept targets at a predefined relative intercept angle. This guidance method can help to improve the hit probability of high-value maneuvering targets. The planar cooperative engagement model and linearized kinematics are established. The varying speed cooperative differential game guidance laws (VSCDGGLs) are derived based on the linearized model and the two-sided optimization problem. To verify the accuracy of the cooperative guidance laws, conjugate point analysis and numerical simulations are conducted to examine the performance of the guidance laws. The results indicate that compared with the cooperative guidance laws based on the constant speed model, the VSCDGGL exhibits a lower demand for the maneuver advantage of the missiles over the target. It also demonstrates stronger robustness against different evasive target maneuvers in the case of varying speeds of missiles and targets. Missiles using the proposed guidance laws adjust their trajectories earlier to cope with the uncertainty of target maneuvers, thus obtaining lower miss distances and relative intercept angle errors with time-varying speeds.