Sending just one kilogram to Mars can cost a staggering $2.4 million, as demonstrated by the expenses of the Perseverance mission. To overcome the challenges of packing essential supplies for space missions, scientists at NASA Ames Research Center and Stanford University are exploring a groundbreaking concept – zero mass exploration. The idea involves utilizing self-replicating machines, a concept conceived by engineer John von Neumann in the 1940s.

Kenneth C. Cheung, a NASA Ames researcher involved in a recent study published in Science Robotics, explains, “It’s the idea that an engineering system can not only replicate but sustain itself in the environment.” The study focuses on self-reprogrammable metamaterials, which are materials with the ability to change their configuration autonomously, not found in nature.

Inspired by Robert A. Freitas Jr.’s 1980s proposal of a self-replicating interstellar spacecraft, the team advances the technology of reprogrammable metamaterials using prefabricated “voxels” – standardized reconfigurable building blocks. Christine E. Gregg, the lead author of the study, emphasizes the scalability of this approach, drawing parallels with biology’s use of building blocks like amino acids to create complex structures.

In a practical demonstration, the team constructed 256 of these voxels, forming strong 3D structures with carbon-fiber-reinforced polymer. Despite being exceptionally light (density of 0.0103 grams per cubic centimeter), a truss structure made with these voxels demonstrated a remarkable failure load of over 9,000 Newtons, equivalent to supporting more than 900 kilograms.

The real breakthrough came when the team autonomously assembled a shelter using three robots within four and a half days. These robots operated without vision, lidar, or advanced sensors, relying solely on internal reference frames. The process showcased the scalability of the system, with more voxels enabling larger structures and more robotic teams assembling structures faster.

The team’s next target is the Moon, where they plan to build towers for the Artemis 3 mission. The towers, intended for communication and solar panels, are crucial due to the low Sun angle near the Moon’s south pole. The team aims to demonstrate how their reconfigurable building blocks and autonomous robots can efficiently construct towers over 100 meters high, maximizing sunlight exposure and ensuring effective communication in the lunar environment. The upcoming papers in March will delve deeper into this revolutionary application of zero mass construction in space exploration.

By Impact Lab