Design of a Visual Pose Estimation Algorithm for Moon Landing

TL;DR

This paper proposes a terrain-based absolute navigation algorithm for lunar landings that estimates spacecraft position and attitude by matching crater images to a database, improving landing precision.

Contribution

It introduces a crater-based terrain navigation method that bypasses image processing, focusing on estimation accuracy and crater count effects through simulations.

Findings

Algorithm achieves accurate position and attitude estimation.

Increased crater count improves estimation accuracy.

Simulation results demonstrate robustness of the method.

Abstract

In order to make a pinpoint landing on the Moon, the spacecraft's navigation system must be accurate. To achieve the desired accuracy, navigational drift caused by the inertial sensors must be corrected. One way to correct this drift is to use absolute navigation solutions. In this study, a terrain absolute navigation method to estimate the spacecraft's position and attitude is proposed. This algorithm uses the position of the craters below the spacecraft for estimation. Craters seen by the camera onboard the spacecraft are detected and identified using a crater database known beforehand. In order to focus on estimation algorithms, image processing and crater matching steps are skipped. The accuracy of the algorithm and the effect of the crater number used for estimation are inspected by performing simulations.