Autonomous navigation for powered descent phase of Chang’E-3 lunar lander
ZHANG Hong-hua
LI Ji
GUAN Yi-feng
HUANG Xiang-yu
Abstract：The powered descent phase of Chang’E–3 lunar lander is fully autonomous. The navigation system obtains the lander’s movement information such as position, velocity and attitude, and introduces them to the guidance and control system. To meet the requirement that landing on the lunar surface with terrain uncertain, an integrated navigation scheme is contrived, which combines a multiplicity of data types including a strap-down inertial measurement unit, a laser altimeter and a capable radar altimeter and velocimeter. The information from laser and radar altimeters are fused to correct the alti-tude output of INS, and the data from multi-beam doppler velocity radar are combined to decrease the velocity calculation error of INS. To simplify the algorithm, filters with variable gains which are calculated by predesigned functions are used to replace normal extend Kalman filters. And the validation of measurements from altimeters and radars are verified by some altitude-varing thresholds before they are introduced to these filters. The flight results demonstrate that this navigation method is reliable and effective to the Chang’E–3 lunar landing mission.
Keywords：Chang’E-3 lunar landerpowered descentautonomous navigationintegrated navigation
Publication Date：2014-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 1686-1694 )