A Caltech robotic system funded by the U.S. Defense Advanced Research Projects Agency assembled a satellite structure in orbit without astronauts at the controls, Space.com reported, citing a Nov. 5 statement from the project team¹.

Sergio Pellegrino, a Caltech aerospace and civil engineering professor who leads the demonstration, said it was the first time a structure had been autonomously constructed in space¹. The project is called Autonomous In-Space Tensioned Reflector Assembly, or ASTRA¹. DARPA, in its own Nov. 5 release, called the work the first demonstration of automated in-space assembly.

Space.com said the robotic truss builder used Kapton film, composite fiber tubes and aluminum joints to assemble a reflective antenna structure about 1.4 meters (4.5 feet) wide¹. Pellegrino said the work could apply to astronomy, communications and large solar arrays for space solar power¹.

The effort is part of DARPA's Novel Orbital and Moon Manufacturing, Materials, and Mass-efficient Design program, or NOM4D¹. Program manager Andrew Detor said the goal is scalable construction of very large structures in space, on the order of hundreds of meters or kilometers, which he said cannot be achieved today¹.

DARPA said the Caltech payload launched into orbit aboard SpaceX's Transporter-16 mission at the end of March, hosted on Momentus Inc.'s Vigoride platform.

The payload flew with two prebuilt truss sections, a robotic manipulator and parts to finish the rest of the truss¹. In brief communications windows totaling about 15 minutes a day, engineers sent commands as the robot picked up components, placed them and built on an assembly plate¹.

The team was not able to finish the entire truss in time, Space.com said, though Pellegrino framed the demonstration as a success¹. NOM4D is also supporting a University of Illinois Urbana-Champaign project at the International Space Station on hardening carbon tubes in orbit¹.