A robot just built a structure in space for the first time

Pushing big things into Earth’s orbit is no easy task. Putting lots of small things into orbit and then assembling them into something big is easier, but requires a human touch.If there’s one thing we know about humans and space, it’s that the less time we spend floating in a radiation-filled vacuum, the better.A robot designed by Caltech and funded by DARPA has recently demonstrated a potential solution to space construction by assembling an antenna’s truss from individual components in orbit. Researchers have described it as the first autonomous construction of a structure in space.Think flat-pack furniture, only with more expensive delivery.A key part of the Autonomous In-Space Tensioned Reflector Assembly project, or ASTRA for short, the robotic builder was meant to build a 1.4-meter-wide (4.6-foot) reflector antenna from an assortment of composite tubes, aluminum joints, and reflective film. The ASTRA truss builder was able to construct a third bay of a truss structure in orbit. The space demonstration was funded by DARPA as part of its NOM4D program.Caltech/Momentus Time limitations restricted the robot’s task to a single support. Two truss sections traveled up pre-assembled; the robot then assembled a third.It might not be a complete communications dish ready to phone home, but according to Andrew Detor, program manager for DARPA’s Novel Orbital and Moon Manufacturing, Materials and Mass-efficient Design (NOM4D) program, the demonstration is a significant step towards building massive structures in space kilometers in scale.“Nothing approaching that scale can be achieved today,” says Detor. Artist's concept of a potential envisioned future for NOM4D technology for structural assembly and novel composite-forming process experiments in space.University of Illinois Urbana-Champaign NOM4D’s broader vision involves shipping raw materials into orbit and manufacturing structures designed for life in space. Antennas, optics, and solar arrays could then be engineered around their working environment, with less emphasis on surviving launch as finished structures. DARPA likens the approach to Tinkertoys or K'Nex. Repeating a relatively straightforward construction sequence could eventually produce structures far larger than the machine doing the building. “Within the automated assembly box, each section is built piece by piece, a reflective mesh is attached, and the assembled sections are deployed as they are complete. There are no complicated robotics or advanced algorithms; it’s just solid engineering from the Caltech team to combine operations in a way that scales,” explains Detor. NOM4D – ASTRA Assembly Demonstration Just like the robot, however, the word “automated” is currently doing a bit of heavy lifting. The robot performed the assembly while its terrestrial support crew was kept busy. With contact was restricted to a few daily windows of just 15 minutes, engineers checked photographs and solved problems using a duplicate model in their laboratory before issuing the robot with commands.Space construction itself has a rich history of robotics. Canadarm2 helped assemble the International Space Station, maneuvering large components into position while astronauts carried out installation work. Those operations joined hardware already manufactured on Earth, rather than having a robot construct larger objects from a handful of smaller pieces. Precedent for making complex components from scratch also exists. In 2014, a 3D printer aboard the station squeezed out a faceplate for its own extruder casing. Printing replacement parts for the printer itself was an ideal way to prove the value of an orbiting machine shop.NASA's Archinaut One project, also called OSAM-2, moved the concept outside of the ISS. Plans called for manufacturing structural beams in orbit and deploying a solar array, combining 3D printing with robotic manipulation. Surface demonstrations showed some promise for the technology before the project ended in 2023.ASTRA now provides an orbital proof of concept for assembling larger structures piece by piece. Building the first section is how every construction project starts. Even when the nearest hardware store is a world away.Sources: Caltech, DARPA