Autonomous Entry Guidance based on 3-D Gliding Trajectory Analytical Solution

In this paper, an autonomous entry guidance is developed for hypersonic glide vehicle based on 3-D gliding trajectory analytical solutions. In the derivation of the solutions, a new dynamics of downrange, crossrange and heading angle with respect to energy is established based on the Auxiliary Geocentric Rotation (AGR) frame. After that, the new guidance uses the downrange formula to determine the longitudinal reference profile in real time, and regulates the first bank reversal by the crossrange formula to eliminate the terminal crossrange error. Subsequently, the second bank reversal is corrected by several trajectory simulations to guarantee terminal constraints. The simulations show that the new entry guidance has high accuracy and can handle various terminal conditions.