
Flight Test Sheds New Light on In-Space 3D Printing, Propellant Slosh
FLIGHT SUMMARY
The Galactic 7 flight test aboard Virgin Galactic’s VSS Unity sent two university payloads — from the University of California, Berkeley and Purdue University — on suborbital flight tests supported by NASA’s Flight Opportunities program. The reusable suborbital spaceship reached an altitude of more than 54 miles and provided approximately three minutes of microgravity. These conditions provided research teams the opportunity to evaluate a new 3D printer’s in-space performance and to study of how the sloshing of liquid propellant affects spacecraft pointing.
flight provider
Virgin Galactic
Flight Test Platform
Reusable suborbital spaceship
flight date
June 8, 2024
location
Spaceport America in southern New Mexico
“To address critical capabilities needed for space exploration, researchers must advance their technologies as quickly as possible. Our program enables them to rapidly move from the lab to flight test, and in many cases multiple flight tests across different vehicles. This allows them the invaluable opportunity to learn from initial tests, implement improvements, and then fly again.”
Danielle McCulloch, program manager, NASA’s Flight Opportunities program
The phrase “do me a solid” has new meaning when it comes to in-space manufacturing.
About the Payload
Rather than printing in layers, UC Berkeley’s new additive manufacturing system uses light to solidify liquid and gel materials in a single step in microgravity. The suborbital flight test provided an opportunity to mature this technology for future use in crewed space exploration missions or producing commercial products in low Earth orbit.
Jointly developed by the UC Berkeley and Lawrence Livermore National Laboratory, the multi-material manufacturing technique is known as computed axial lithography.
Applications
The space-based version aims to rapidly meet astronauts’ urgent needs. These might range from printing spare parts for spacecraft machinery to addressing medical-related issues during long-duration missions. The technology could even be used to bioprint organs in low Earth orbit for patients on Earth.
“We’re looking to print a range of things in space, from mechanical engineering tools to clips for closing wounds,” said principal investigator Hayden Taylor. “We’re also looking into restorative dental applications. So, if an astronaut chips a tooth on a long mission and we have a scan of their mouth, this machine could print a crown on demand.”
Flight Test Objectives
Working with the Conseil National de Recherches Canada, Taylor and the rest of the research team are striving to reduce the size and cycle time of in-space additive manufacturing systems and increase the quality of printed pieces. Their other goals include minimizing the required level of operator experience while increasing scalability and modularity. They also want to offer new capabilities, such as embedding an existing item within a 3D printed object.
Flight Testing Heritage
The flight with Virgin Galactic builds on two previous UC Berkeley tests, which Flight Opportunities also supported. During parabolic flights aboard Zero Gravity Corporation’s G-Force One aircraft, researchers experimented with printing various objects during 20-second rounds of reduced gravity. They leveraged the results of those flight tests to adjust their technique, improve hardware and data collection, and integrate the post-processing usually performed separately to finish a printed piece.

Researchers examine how sloshing propellant affects spacecraft pointing.
About the Payload
Researchers designed this technology to gather data that may lead to precise guidance, navigation, and control (GNC) models of liquid response and deliver reduced-gravity measurements to update existing models.
Applications
Spacecraft pointing maneuvers orient a vehicle for docking or Earth reentry and help optimize the operations of imaging satellites orbiting the Earth, Moon, and Mars. Rapid, accurate pointing maneuvers require advance knowledge of the time needed for propellant sloshing to settle to a sufficiently small level.
Flight Test Objectives
Since precise modeling of slosh in microgravity is not possible computationally or through testing on Earth, the measurements made during this flight test with Virgin Galactic will be used to help plan spacecraft movements more precisely, thereby increasing spaceflight operational safety and fuel efficiency.
