How To 3D Print A Rocket, No, For Real
A new video explains the secrets of 3D printing rocket engines.
The video, produced by Hackaday from a session at their recent Supercon, has Relativity Space’s Bryce Salmi explaining the process and challenges of 3D printing a highly complex component, the rocket engine.
Relativity Space is a California-based startup company hoping to develop a very sophisticated rocket system by leveraging a number of modern technologies, including 3D printing. We’ve covered them previously, showing off their incredible custom-built metal 3D printer, the Stargate, which uses multiple robot arms and a wire deposition process to 3D print very large components.
Salmi’s talk is quite interesting because it provides a look at the findings their company has encountered during the design and build of their rocket engine, the AEON 1. It seems there are effects on the entire design process, even though only certain structures are 3D printed.
Salmi explained the main advantage of using 3D printing, as should be known to most readers: dramatic reduction in labor requirements.
He says that previous rocket engines required as many as 5,600 parts, whereas the AEON 1 could be made in as little as only three!
But consider the resources required to design, make, inspect, handle, store, inventory, assemble, replace and repair 5,600 different parts. That’s an incredible amount of effort required. Now consider how much less work it would be to deal with only three parts. You get the idea.
It’s particularly evident in the manufacturing process, where tooling and jigs are mostly eliminated. In traditional manufacturing, a significant amount of time is usually required to gather and set up all the required tooling before anything can be made. That’s not the case with 3D printing, as you simply “print”.
The result is that Relativity Space is building product at a rate 5X faster than expected. Their goal is to literally build and fly a rocket in only 60 days, and they’re actually doing it, thanks to 3D printing techniques.
Some of the interesting observations Salmi describes are that their custom 3D printer, the Stargate, is able to work collaboratively. With its multiple robot arms, the software can deploy arms to different portions of the same large print simultaneously, dramatically cutting down on print time. Of course, the resulting print still requires painting machining and inspection.
Those components leveraged the ability of 3D printing to produce very light, highly complex parts for use in the rocket, which are welcome features.
Salmi explains that rocketry is actually a low-volume business with high part costs, and this is ideal for 3D printing applications, as some low-volume manufacturers have discovered in other industries.
Here is a very interesting twist: Salmi says that 3D printing is so speedy that it can take on issues that might previously have been dispatched for resolution to other teams within the project, if a choice is possible to resolve tradeoffs. Now because 3D printing is so flexible, it can sometimes solve problems before other units can do.
Of course, they’ve designed their system to anticipate the iteration that’s possible with 3D printing, so they can indeed take full advantage. This is something that few companies starting in 3D printing realize: the design must be different than you expect to get full value. Salmi says, “3D printing affects everything!” As an example, he says that the mechanical design can actually affect circuit board and software design.
You’ll get a lot more by watching the video itself, of course.
But if you want even more, it turns out that Relativity Space is hiring. Check out their careers page if interested.