Long-Reach Robotic Cleaning for Lunar Solar Arrays

Abstract

Commercial lunar activity is accelerating the need for reliable surface infrastructure and routine operations to keep it functioning. Maintenance tasks such as inspection, cleaning, dust mitigation, and minor repair are essential to preserve performance and extend system life. A specific application is the cleaning of lunar solar arrays. Solar arrays are expected to provide substantial fraction of lunar surface power and operate for months to years, supplying continuous energy to landers, habitats, and surface assets, making sustained output mission-critical. However, over time lunar dust accumulates on these large solar arrays, which can rapidly degrade panel output and reduce mission lifetime. We propose a small mobile robot equipped with a long-reach, lightweight deployable boom and interchangeable cleaning tool to perform gentle cleaning over meter-scale workspaces with minimal human involvement. Building on prior vision-guided long-reach manipulation, we add a compliant wrist with distal force sensing and a velocity-based admittance controller to regulate stable contact during surface cleaning. In preliminary benchtop experiments on a planar surface, the system maintained approximately 2 N normal force while executing a simple cleaning motion over boom lengths from 0.3 m to 1.0 m, with RMS force error of approximately 0.2 N after initial contact. These early results suggest that deployable long-reach manipulators are a promising architecture for robotic maintenance of lunar infrastructure such as solar arrays, radiators, and optical surfaces.

Figures (3)

• Figure 3: Concept illustration of a mobile base (wheeled rover) equipped with a long-reach (5-10m) deployable manipulator arm for cleaning large solar arrays. We acknowledge the use of AI for image generation and took inspiration from conceptual art developed by Lockheed Martin lockheed2022moonBright.
• Figure 4: Control overview: measured normal force $F_n$ goes through a simple admittance control block to set approach normal velocity $v_n$. Tangential velocity $v_t$ is commanded separately for surface following. Distal force sensing defines the surface normal, so the robot keeps gentle, steady contact while it moves along the panel.
• Figure 5: Experimental setup and representative trial. (A) Long-reach deployable boom with compliant self-aligning wrist, inline 6-axis force sensor, and soft, wiper pad contacting a vertical surface. (B) Force (top) and commanded normal velocity (bottom) during approach (blue), force stabilization (green), and trajectory following (orange) with a normal-axis admittance controller tracking with desired force $F_{des}=-2N$