θ-D approach-based 3-dimensional terminal guidance law with impact angle constraint

A θ-D approach-based 3-dimensional( 3D) terminal guidance law with impact angle constraint is proposed for the hypersonic glide vehicle( HGV). Considering the motion characteristics of the HGV and requirement of impact angle,the kinematical equations of the guidance problem are formulated in 3D space. By redefining the state variables and adopting the θ-D suboptimal approach,a closed-form guidance law with impact angle constraint is obtained without channel decoupling. Furthermore,the guidance law doesn't require excessive online computations. The simulation results demonstrate that the effectiveness and efficiency of the proposed guidance law.