Abstract: The deepspaceexploration return vehicles reenter the earth under bad conditions. To assure the safety and accuracy of the return, both the LQR referencetrajectory and the predictorcorrector guidance approaches are researched in this paper. The adaptability to the reentry initial conditions and the landing accuracy of both guidance methods are analyzed. The numerical simulation is done for the return vehicles with the second cosmic velocity. The results show that the predictorcorrector guidance gets smaller range error than the LQR one with a relatively large initial error.

Key words: deep space exploration, reentry guidance, LQR guidance, predictorcorrector guidance