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Photograph of Tim Ellis

Tim Ellis

Relativity Space
Country of birth: US

Developed a massive 3D metal printer—for building an entire rocket

  • by Russ Juskalian
  • Tim Ellis uses 3D metal printing, machine learning, and automated manufacturing to build rockets and satellites. Relativity Space uses this approach to build rockets with just a thousand moving parts (see our profile of the company). A typical rocket, in comparison, has 100,000 moving parts—which not only makes the rocket more expensive but also gives it that many more ways to fail.

    Step one for Ellis was building a massive 3D metal printer that stands about 20 feet (6 meters) tall and can print 95% of the parts for a rocket that’s up to 10 feet in diameter and 100 feet tall. Step two was writing the code to automate much of the process and using machine learning to optimize which parts to print, and how to do it.

    Relativity Space says it will soon be able to print and iterate a design in as little as 60 days, compared with the industry standard of 18 months—dramatically bringing down costs. This earned the company its first contract, with Telesat, a major Canadian satellite operator, to build rockets to launch some of the company’s satellites starting in 2021.

    “We founded Relativity with the long-term vision of 3D-printing the first rocket made on Mars,” says Ellis. “Over time we’ll actually shrink the factory to the point where then we could launch it to another planet.”