Madison Reporter

Researchers at the University of Wisconsin–Madison have achieved a significant milestone in the field of in-space manufacturing by successfully 3D printing RAM device units in zero gravity for the first time. This achievement is a crucial step towards enabling long-distance space flights, where astronauts cannot rely on earth for replacement hardware components.

The team's accomplishment took place during a parabolic test flight at Fort Lauderdale-Hollywood International Airport in Florida in early March 2024. The research, funded by NASA and led by UW Industrial and Systems Engineering Assistant Professor Hantang Qin, aims to develop in-space manufacturing capabilities for electronic components such as semiconductors, actuators, and sensors.

Despite encountering technical glitches during their initial test flights, the team managed to troubleshoot potential causes after intensive workdays leading up to their third and final flight. Rayne Wolf, a PhD student from Potosi, Wisc., and one of the team leads said, “A lot rides on these experiments.”

The researchers developed an alternative 3D printing method called electrohydrodynamic (EHD) printing which can function in zero-gravity environments. This technique applies electrical force to drive the flow of liquid materials through an extremely thin nozzle that’s only 30 micrometers in diameter.

Qin explained that EHD printing technology has advantages beyond its ability to function in zero-gravity environments. He stated, “But using our printing system, we can make the droplet way smaller than the size of nozzle,” he says. “Given a 2-micrometer nozzle, we can make a nanoscale pattern. That’s the huge advantage of this.”

After resolving issues related to plane engine vibrations affecting printer calibration sensors, they successfully produced more than a dozen units with zinc oxide, a semiconducting ink, and several more with polydimethylsiloxane, an insulating polymer ink during their final test flight.

The researchers are planning to return to Florida in August and November 2024 for two more test flights. They aim to incorporate their EHD technology into an industry partner’s multi-tool 3D printer, and then progress from printing individual units to full semiconducting devices.

The ultimate goal is to test their technology aboard the International Space Station. “If we can send this up to the ISS,” says PhD student Liangkui Jiang, who’s worked on the project since conception, “it would be a happy ending.”

This research was supported by NASA (award numbers 80MSFC23PA012 and 80NSSC2XK1188).