The proposed innovation is the development and validation of bulk regolith infrastructure for use in lunar surface construction. The focus is on designing and testing 2D and 3D rego-works, such as trenches, berms, and overburden structures, that can protect astronauts and mission assets from hazards such as GCR, SPEs, micrometeorite impacts, plumes, moonquakes, and extreme thermal swings. The proposed work seeks to establish structural design criteria, build and test compacted regolith structures that represent real use-case conditions with applied loads, and prototype solutions to enhance the potential of regolith as a construction material for lunar surface infrastructure. The proposal examines the limitations of untreated regolith as a construction material and presents a novel technique of polymeric doping as a method to improve the strength of lunar regolith. Experimental results of three methods to improve the strength of regolith, including compaction at 60 psi, vibration compaction at 20 psi, and fortifying regolith through polymeric doping and applied heat. The third method was successful in stabilizing unconstrained lunar regolith and exceeded the design load of 5.2 psi. These results will inform the design of a prototype heated vibrating compaction (HVC) implement that meets the payload and energy budget constraints of the CLPS mission. The team will explore different heating methods and pre-heating methods for cold regolith, including passive solar. The HVC implement will be used to construct regolith specimens of various geometries to validate structural performance first in ambient, then in vacuum. Autonomous processes will be used where possible, and tests will be performed with regolith-additive mix at various concentrations. ConOps involves using HVC implements and a small polymer payload to build bulk regolith infrastructure on the lunar surface autonomously, with a baseline 2D demonstration and 3D demonstrations as stretch goals. Anticipated
Benefits: The proposed innovation is of enormous benefit to NASA as a near-term solution for building robust lunar surface infrastructure using mostly bulk regolith. Similar to terrestrial rammed earth structures, our solution to compact and fortify regolith into three dimensional constructs such as walls, berms, trenches, and overburden structures can also be applied to 2D pathways, landing pad substrates, and flat operational surfaces. These constructs are essential for protecting astronauts and mission assets from the extreme lunar environment. Potential non-NASA applications include commercial space exploration and development, as well as potential applications in terrestrial construction and mining industries: autonomous methods to fortify earthworks which could be used in remote or hazardous locations, reducing the need for heavy equipment and transport of building materials, increasing safety, efficiency and reducing costs.
