Design, Implementation, and Validation of a State Estimator for the MoonRanger Lunar Rover

May 2026

Design, Implementation, and Validation of a State Estimator for the MoonRanger Lunar Rover

Authors:

Tushaar Jain

Abstract:

The MoonRanger Lunar rover will demonstrate continuous, on-board, long-range autonomous navigation at the Moon's South Pole. In this thesis, we describe how MoonRanger estimates its position and orientation using several sensors: an Inertial Measurement Unit (IMU), Sun Sensor, wheel encoders, and cameras. We thoroughly review the state estimation approaches for space vehicles. Then, we introduce MoonRanger's state estimator, which performs visual-wheel-inertial odometry, the core of which is an attitude estimator. We derive the state estimator using detailed sensor models, accounting for many error sources in the measurements. Next, we develop a custom simulation infrastructure, which enables rapid iteration, testing, and Monte Carlo analyses of the algorithms. We use this simulator to validate the estimator's design through ablation studies. Lastly, we prove the estimator's effectiveness through a field test.

We cover several implementation details important to making the software computationally efficient, memory-safe, debug-able, and robust to uncertainties. In the appendices, we provide a thorough background of 1) the mathematical fundamentals of state estimation, 2) IMU noise characterization and 3) an in-field method for calibrating an IMU's pitch to reduce elevation drift. These algorithms, analyses, and implementation details can serve as a guide to developing state estimators for future planetary rovers.

Notes:

@mastersthesis{Jain-2026-88290,
author = {Tushaar Jain},
title = {Design, Implementation, and Validation of a State Estimator for the MoonRanger Lunar Rover},
year = {2026},
month = {May},
school = {Carnegie Mellon University},
address = {Pittsburgh, PA},
number = {CMU-RI-TR-26-31},
}
Copyright notice: This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. These works may not be reposted without the explicit permission of the copyright holder.