LunarNav: Crater-based Localization for Long-range Autonomous Lunar Rover Navigation

TL;DR

LunarNav introduces crater-based algorithms enabling lunar rovers to autonomously estimate their global position and heading with high accuracy, supporting long-range navigation essential for future lunar exploration missions.

Contribution

The paper presents novel crater detection and matching algorithms integrated into a framework for autonomous lunar rover localization with sub-5 meter accuracy.

Findings

Crater detection algorithms perform reliably in sunlit conditions.

Crater matching achieves high accuracy in identifying known features.

Localization error is estimated to be less than 5 meters during daytime.

Abstract

The Artemis program requires robotic and crewed lunar rovers for resource prospecting and exploitation, construction and maintenance of facilities, and human exploration. These rovers must support navigation for 10s of kilometers (km) from base camps. A lunar science rover mission concept - Endurance-A, has been recommended by the new Decadal Survey as the highest priority medium-class mission of the Lunar Discovery and Exploration Program, and would be required to traverse approximately 2000 km in the South Pole-Aitkin (SPA) Basin, with individual drives of several kilometers between stops for downlink. These rover mission scenarios require functionality that provides onboard, autonomous, global position knowledge ( aka absolute localization). However, planetary rovers have no onboard global localization capability to date; they have only used relative localization, by integrating combinations of wheel odometry, visual odometry, and inertial measurements during each drive to track position relative to the start of each drive. In this work, we summarize recent developments from the LunarNav project, where we have developed algorithms and software to enable lunar rovers to estimate their global position and heading on the Moon with a goal performance of position error less than 5 meters (m) and heading error less than 3-degree, 3-sigma, in sunlit areas. This will be achieved autonomously onboard by detecting craters in the vicinity of the rover and matching them to a database of known craters mapped from orbit. The overall technical framework consists of three main elements: 1) crater detection, 2) crater matching, and 3) state estimation. In previous work, we developed crater detection algorithms for three different sensing modalities. Our results suggest that rover localization with an error less than 5 m is highly probable during daytime operations.