Scout-Rover cooperation: online terrain strength mapping and traversal risk estimation for planetary-analog explorations

Shipeng Liu; J. Diego Caporale; Yifeng Zhang; Xingjue Liao; William Hoganson; Wilson Hu; Shivangi Misra; Neha Peddinti; Rachel Holladay; Ethan Fulcher; Akshay Ram Panyam; Andrik Puentes; Jordan M. Bretzfelder; Michael Zanetti; Uland Wong; Daniel E. Koditschek; Mark Yim; Douglas Jerolmack; Cynthia Sung; Feifei Qian

arXiv · 2602.18688

Scout-Rover cooperation: online terrain strength mapping and traversal risk estimation for planetary-analog explorations

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Abstract

Robot-aided exploration of planetary surfaces is essential for understanding geologic processes, yet many scientifically valuable regions, such as Martian dunes and lunar craters, remain hazardous due to loose, deformable regolith. We present a scout-rover cooperation framework that expands safe access to such terrain using a hybrid team of legged and wheeled robots. In our approach, a high-mobility legged robot serves as a mobile scout, using proprioceptive leg-terrain interactions to estimate regolith strength during locomotion and construct spatially resolved terrain maps. These maps are integrated with rover locomotion models to estimate traversal risk and inform path planning. We validate the framework through analogue missions at the NASA Ames Lunar Simulant Testbed and the White Sands Dune Field. Experiments demonstrate (1) online terrain strength mapping from legged locomotion and (2) rover-specific traversal-risk estimation enabling safe navigation to scientific targets. Results show that scout-generated terrain maps reliably capture spatial variability and predict mobility failure modes, allowing risk-aware path planning that avoids hazardous regions. By combining embodied terrain sensing with heterogeneous rover cooperation, this framework enhances operational robustness and expands the reachable science workspace in deformable planetary environments.

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Shipeng Liu, J. Diego Caporale, Yifeng Zhang, Xingjue Liao, William Hoganson, Wilson Hu, Shivangi Misra, Neha Peddinti, Rachel Holladay, Ethan Fulcher, Akshay Ram Panyam, Andrik Puentes, Jordan M. Bretzfelder, Michael Zanetti, Uland Wong, Daniel E. Koditschek, Mark Yim, Douglas Jerolmack, Cynthia Sung, Feifei Qian. 2026-02-21. Scout-Rover cooperation: online terrain strength mapping and traversal risk estimation for planetary-analog explorations. https://arxiv.org/abs/2602.18688

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