Space Maintenance Robotics: Evidence and research priorities for magnetic surface crawlers

Magnetic surface crawlers are a proposed approach to inspecting and maintaining compatible spacecraft structures. This narrative technical review distinguishes documented orbital operations from suborbital experiments, ground demonstrations and prospective applications. It identifies surface compatibility, controlled attachment and release, task reaction loads, navigation, environmental qualification and recovery as questions for a staged research program. Proposed inspection, assembly support and maintenance roles are hypotheses rather than demonstrated capabilities. No new experiments, simulation results or performance measurements are reported. Revised preprint by Mohammad Bahareth, 28 October 2026. Original ResearchGate record: https://doi.org/10.13140/RG.2.2.17871.19363. The original CC0 dedication remains unchanged. Author-owned new contributions in this revision are also released under CC0; third-party rights are not waived. AI tools assisted reference checking and revision, as disclosed in the manuscript. This is a preprint, with no claim of peer review.