Landmark tracking based autonomous navigation schemes for landing spacecraft on asteroids

Autonomous optical navigation schemes for pinpoint landing of spacecraft on asteroids are considered. Due to the long communication delay and complicated dynamic environment close to asteroids, traditional spacecraft navigation and control using the deep space network (DSN) is not suitable for the precise landing of spacecraft on asteroids. Then it is necessary to develop new autonomous navigation algorithms for future asteroid sample and return missions. To meet this requirement, this paper presents two landmark tracking navigation algorithms based on nonlinear least squares (NLS) and extended Kalman filter (EKF). The validity of the proposed navigation schemes is confirmed by numerical simulation.