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Terrain relative navigation for precise lunar landing using crater matching algorithm

Under GPS-denied conditions, an inertial navigation diverges easily due to integration drift in the measurement of acceleration and angular velocity. Therefore, a terrain relative navigation (TRN) is applied to correct the drift error for precise lunar landing mission. Diverse sensors are used for the TRN in these days, such as a Light and Detection and Ranging (LIDAR), laser altimeter, and optical camera. TRN algorithms can improve navigation performance by combining inertial navigation data and terrain measurement data from those sensors. In this paper, a simulation of TRN with an optical camera, IMU by using crater matching algorithm is performed. The craters made by colliding with other solid body can remain longer on the lunar surface without being eroded, because there is no air and liquid water in the Moon. Therefore, it can be utilized as appropriate features for TRN even in lost in space.