Impact-Angle-Constrained Cooperative Guidance for Salvo Attack

This paper proposes distributed cooperative guidance laws for multiple missiles with constant speeds to achieve impact-angle-constrained salvo attack against a stationary target in both two-dimensional (2D) and three-dimensional (3D) scenarios. First, the 2D cooperative guidance law is derived based on an optimal impact angle control guidance (IACG) law, which is augmented by a cooperative guidance term to ensure consensus of times-to-go in a fixed time before interception. To avoid singularity, an auxiliary function with three candidates is introduced into the cooperative guidance term. Then, coplanar cooperative guidance (CCG) and planar pursuit guidance (PPG) commands are, respectively, derived to construct the 3D cooperative guidance law. The CCG command is based on the coplanar assumption and the 2D cooperative guidance law, whereas the PPG command drives the velocity, line of sight (LOS), and desired impact vectors onto one engagement plane by geometric operations of vectors. Unlike existing 3D cooperative guidance laws, the proposed one does not require missile speed adjustment for salvo attack. The fixed-time stability and effectiveness of the proposed guidance laws are theoretically analyzed. The criteria for selecting all guidance parameters are provided to facilitate the guidance design. Finally, numerical simulations are conducted to support the analytical findings.