Scalable Model-Based Discrete Mode Estimation for a Lunar Rover Power System

##plugins.themes.bootstrap3.article.main##

##plugins.themes.bootstrap3.article.sidebar##

Published Jul 3, 2026
Annabel Gomez Zaki Hasnain Michel D. Ingham Seung H. Chung Brian C. Williams

Abstract

Reliable autonomous operation of planetary rovers requires robust onboard monitoring and diagnosis of power systems under uncertain and dynamic conditions. This work presents a model-based mode estimation framework for a simplified rover power system that combines physics-based modeling with probabilistic reasoning to estimate system and environmental state, including anomalous behavior. The approach adapts the Miniature Mode Estimation (Mini-ME) architecture to perform real-time belief tracking over discrete component modes based on noisy measurement signals including voltage, current, temperature, and state of charge, and command inputs into the system. Mini-ME is a system health management tool that monitors components, diagnoses faults in real-time, and supports downstream system recovery. We simulate the physics of the simplified power system under varying loads using a lumped parameter equivalent circuit model that captures the electrical and thermal behavior of the battery. A compiled automaton is used to encode admissible probabilistic state transitions and observation likelihoods derived from sensor models. By compiling out the combinatorial search and integrating these representations within a Bayesian update process, the system efficiently detects, isolates, and diagnoses anomalies arising from faults or unexpected operating regimes. The simulation results demonstrate accurate recovery of hidden system modes during charge-discharge cycles, illustrating how model-based reasoning supports autonomous fault diagnosis and system health management in autonomous missions. This of the paper provides a thorough set of computational experiments to evaluate the performance of compiled mode estimation, versus uncompiled mode estimation, on space relevant benchmarks.

How to Cite

Gomez, A., Hasnain, Z. ., Ingham, M. D., Chung, S. H. ., & Williams, B. C. . (2026). Scalable Model-Based Discrete Mode Estimation for a Lunar Rover Power System. PHM Society European Conference, 9(1), 1–12. https://doi.org/10.36001/phme.2026.v9i1.5067
Abstract 0 | PDF Downloads 0

##plugins.themes.bootstrap3.article.details##

Keywords

Model-Based Diagnosis, Mode Estimation, Autonomous Systems, System Health Management, Compiled Inference, Probabilistic Reasoning

References
Aaseng, G., Do, M., Frank, J., Fry, C., & Sweet, A. (2023). Integrating planning, diagnosis, and execution for vehicle systems management (Tech. Rep.). Intelligent Systems Division, NASA Ames Research Center. Retrieved from https://ntrs.nasa.gov/citations/20230004265

Albee, A., Battel, S., Brace, R., Burdick, G., Casani, J., Lavell, J., ... Dipprey, D. (2000, March). Report on the loss of the Mars Polar Lander and Deep Space 2 missions (Tech. Rep. No. JPL D-18709). NASA Jet Propulsion Laboratory. Retrieved from https://ntrs.nasa.gov/api/citations/20000061966/downloads/20000061966.pdf

Ayton, B., Reeves, M., Timmons, E., Williams, B. C., & Ingham, M. D. (2020). Toward information-driven and risk-bounded autonomy for adaptive science and exploration. In AIAA ASCEND Conference. Cambridge, MA.

Bernard, D., Dorais, G., Gamble, E., Kanefsky, B., Kurien, J., Man, G. K., ... Tung, Y.-W. (1999). Spacecraft autonomy flight experience: The DS1 Remote Agent experiment. In Proceedings of the AIAA Conference. Pasadena, CA.

Chung, S. H., Van Eepoel, J. M., & Williams, B. C. (2001). Improving model-based mode estimation through offline compilation. In Proceedings of the I-SAIRAS 2001 Conference. Montreal, Canada. Retrieved from https://groups.csail.mit.edu/mers/old-site/papers/isairas01_minime.pdf

Hasan, A., Tahavori, M., & Midtiby, H. S. (2023). Model-based fault diagnosis algorithms for robotic systems. IEEE Access, 11, 2250–2258. doi: 10.1109/ACCESS.2022.3233672

Hayden, S. C., Sweet, A. J., & Shulman, S. (2005). Lessons learned in the Livingstone 2 on Earth Observing One flight experiment (Tech. Rep.). NASA Ames Research Center. Retrieved from https://ntrs.nasa.gov/api/citations/20060006365/downloads/20060006365.pdf

Ingham, M., Hasnain, Z., Amini, R., Ardito, S., Bandyopadhyay, S., Bocchino, R., ... Rouquette, N. (2024). Onboard planning and execution of mobility and telecommunications for the Endurance lunar rover. In AIAA ASCEND Conference. Pasadena, CA.

Jagdale, S. (2023). Modeling Li-ion batteries with equivalent circuit technology. Retrieved from https://www.powerelectronicsnews.com/modeling-li-ion-batteries-with-equivalent-circuit-technology/

Keane, J. T., et al. (2023). Endurance: Lunar South Pole–Aitken Basin traverse and sample return rover (Tech. Rep.). NASA. Retrieved from https://science.nasa.gov/wp-content/uploads/2023/11/endurance-spa-traverse-and-sample-return.pdf

Moura, L. D., & Bjørner, N. (2008). Z3: An efficient SMT solver. In Tools and Algorithms for the Construction and Analysis of Systems, TACAS 2008, 14th International Conference, held as part of ETAPS 2008, Budapest, Hungary, March 29–April 6, 2008, Proceedings (Vol. 4963, pp. 337–340). Springer. doi: 10.1007/978-3-540-78800-3_24

Murnane, M., & Ghazel, A. (2023, March). A closer look at state of charge (SOC) and state of health (SOH) estimation techniques for batteries. Analog Devices Technical Articles. https://www.analog.com/en/resources/technical-articles/a-closer-look-at-state-of-charge-and-state-health-estimation-tech.html

Muscettola, N., Nayak, P. P., Pell, B., & Williams, B. C. (1998). Remote Agent: To boldly go where no AI system has gone before. Artificial Intelligence, 103(1–2), 5–47. Retrieved from https://www.sciencedirect.com/science/article/pii/S000437029800122X

National Aeronautics and Space Administration. (2025). What is the South Pole–Aitken Basin? https://science.nasa.gov/resource/south-pole-aitken-basin/

Nayak, P. P., & Williams, B. C. (1997). Fast context switching in real-time propositional reasoning. In Proceedings of the National Conference on Artificial Intelligence (pp. 50–56).

Qu, S. (2006). Fast incremental unit propagation by unifying watched-literals and local repair (Unpublished master’s thesis). Massachusetts Institute of Technology.

Williams, B. C., Ingham, M. D., Chung, S., Elliott, P. H., & Hofbaur, M. (2004). Model-based programming of fault-aware systems. AI Magazine, 24(4), 61–75.

Williams, B. C., Ingham, M. D., Chung, S., & Elliott, P. H. (2003, January). Model-based programming of intelligent embedded systems and robotic space explorers. Proceedings of the IEEE, 91(1), 212–237.

Williams, B. C., & Nayak, P. P. (1996). A model-based approach to reactive self-configuring systems. In Proceedings of the Thirteenth National Conference on Artificial Intelligence (AAAI-96) (pp. 971–978). Portland, Oregon, USA: AAAI Press / The MIT Press. Retrieved from https://www.aaai.org/Papers/AAAI/1996/AAAI96-144.pdf

Williams, B. C., & Ragno, R. (2003, June). Conflict-directed A* and its role in model-based embedded systems. Special Issue on Theory and Applications of Satisfiability Testing, Journal of Discrete Applied Mathematics, 155(12), 1562–1595.
Section
Technical Papers