Onboard localization capabilities for planetary rovers to date have used
relative navigation, by integrating combinations of wheel odometry, visual
odometry, and inertial measurements during each drive to track position
relative to the start of each drive. At the end of each drive, a
ground-in-the-loop (GITL) interaction is used to get a position update from
human operators in a more global reference frame, by matching images or local
maps from onboard the rover to orbital reconnaissance images or maps of a large
region around the rover's current position. Autonomous rover drives are limited
in distance so that accumulated relative navigation error does not risk the
possibility of the rover driving into hazards known from orbital images.
However, several rover mission concepts have recently been studied that require
much longer drives between GITL cycles, particularly for the Moon. These
concepts require greater autonomy to minimize GITL cycles to enable such large
range; onboard global localization is a key element of such autonomy. Multiple
techniques have been studied in the past for onboard rover global localization,
but a satisfactory solution has not yet emerged. For the Moon, the ubiquitous
craters offer a new possibility, which involves mapping craters from orbit,
then recognizing crater landmarks with cameras and-or a lidar onboard the
rover. This approach is applicable everywhere on the Moon, does not require
high resolution stereo imaging from orbit as some other approaches do, and has
potential to enable position knowledge with order of 5 to 10 m accuracy at all
times. This paper describes our technical approach to crater-based lunar rover
localization and presents initial results on crater detection using 3D point
cloud data from onboard lidar or stereo cameras, as well as using shading cues
in monocular onboard imagery.

本文介绍了一种基于陨石坑的月球探测器定位技术，通过在轨数据重建陨石坑地图，并利用激光雷达和摄像机识别陨石坑地标，能够实现 5 到 10 米的定位精度。