Abstract:

The guidance technique of suborbital reentry for reusable launch vehicle (RLV) is based on shuttle’s gliding return to launch site (GRTLS). The flight uses openloop guidance and includes three sequential phases: Alpha Reco〖JP6〗very〖JP〗, Nz Hold and Alpha Transition. The main point is to reduce dynamic pressure. The factors contributed to dynamic pressure rate are analyzed, and the guidance strategy is designed to arrest the sink rate. The methods of both alpha and Nz commands design are also given. A closeloop guidance method is proposed to adjust the alpha and Nz commands based on keeping the maximum dynamic pressure near that of the nominal when initial altitude and aerodynamic are uncertain. The simulation results show that the flight constraints are well satisfied.