Vacuum Laser Additive Manufacturing of Lunar Regolith: System Development and Performance Validation

The NASA Moon to Mars architecture outlines several technology development areas enabling sustainable lunar and Martian exploration. This work advances capabilities in in-situ resource utilization (ISRU), infrastructure support, and autonomous robotic systems—contributing options for future mission planners. Locally-sourced regolith construction could support landing pads, habitats, radiation shielding, and dust mitigation structures, aligning with a "make it, not take it" approach to reduce Earth-launch dependence. This presentation directly addresses the WAMS 2026 theme of out-of-Earth manufacturing via planetary surface ISRU.

NASA Marshall Space Flight Center internally designed, built, and demonstrated (TRL 5) a laser regolith directed energy deposition (LR-DED) system for large-scale construction in lunar and Martian environments. The system combines laser powder directed energy deposition (LP-DED) fundamentals with a dust-mitigated, vacuum-rated 6-axis robotic arm and novel processing protocols converting raw regolith into structural components. This system was developed in-house to demonstrate technical feasibility and enable commercial partnerships, with industry partners supplying individual hardware components.

Key design drivers included: (1) no binders or additives, (2) minimal feedstock preprocessing, (3) vacuum compatibility with dust mitigation (TRL 5), and (4) autonomous operation with pre-programmed decision logic. Feedstocks tested include unmodified Lunar Highlands Simulant-1 (LHS-1) and Mars Global Simulant-1 (MGS-1). A vibratory conveyance system fluidizes and delivers powder into the laser interaction zone without consumable gases, reducing logistical burden for sustained planetary operations. In-situ thermal monitoring was integrated for process control and digital twin development.

Process development was conducted on a modified laser powder bed fusion (L-PBF) system, enabling rapid parameter optimization before LR-DED scaling. A decommissioned Concept Laser M1 was refurbished with open-architecture controls and real-time thermal monitoring tuned for regolith melt pools. L-PBF specimens achieved 17 ksi compression strength (ASTM C39), exceeding Portland cement (4-8 ksi) and approaching high-strength concrete (10-12 ksi), indicating suitability for load-bearing structures. X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), and scanning electron microscopy (SEM) confirmed uniform phase distribution and fine-grained morphology.

LR-DED processing succeeded in both atmospheric and high-vacuum environments. Atmospheric specimens exhibited higher density; vacuum specimens showed 5-10% porosity from volatile outgassing but maintained structural integrity. Initial MGS-1 trials confirmed processability within system specifications; parameter refinement continues.