Startup's Robot Arm 70x More Precise Than Current Space Tech

Imagine robots in space so precise they can move with less than a millimeter of error at the end of a 16-foot arm. That's exactly what startup Spaceium just proved is possible.

The San Francisco company successfully tested a robotic actuator in orbit that achieved 0.003 degree rotation accuracy. When attached to a full robotic arm, that level of control means movements smaller than a millimeter at the far end.

"Our technology revolves around how precisely we can transfer fuel," said Ashi Dissanayake, Spaceium's co-founder and CEO. The actuator flew on a SpaceX rideshare mission in November 2024 and passed every test.

Here's why this matters: satellites and spacecraft heading to the Moon or Mars could soon stop at orbiting gas stations instead of carrying all their fuel from Earth. That makes missions cheaper and opens up possibilities that weren't economically feasible before.

Spaceium plans to launch a network of refueling stations in low Earth orbit within two to three years. These stations will store between 10 and 30 metric tons of fuel for up to 10 years, offering what the company calls "really competitive" prices in the industry.

The speed of progress is remarkable. Spaceium was founded in 2023, completed the Y Combinator startup accelerator in 2024, and raised $6.3 million in early 2025. Just two founders built and flew this record-breaking technology in five months.

The Ripple Effect

This breakthrough extends far beyond one company's success. Affordable orbital refueling could transform how we explore space and maintain the satellite networks we rely on daily for GPS, weather forecasting, and communications.

Spacecraft currently must carry every drop of fuel they'll ever need, making them heavier and more expensive to launch. With refueling stations available, missions can launch lighter and travel farther.

Spaceium's second mission flies later this year to continue proving the technology. The company eventually plans to offer spacecraft inspection and repair services, but they're focused on refueling first because the market demand is enormous.

The precision they've achieved solves one of the hardest problems in space robotics. When you're transferring volatile fuel between spacecraft traveling at thousands of miles per hour, millimeter-level accuracy isn't just impressive, it's essential for safety.

Within three years, the first commercial refueling station could be operating in orbit, turning science fiction into everyday reality.