Case Study: Yet Another Way 3D Printing is Affecting Spacecraft Design

Some of the most exciting 3D printing applications I’ve read and written about have to do with spaceships. Pretty much all of the major aerospace agencies are turning to 3D printing to do incredible things that have never been done before with airplanes and spacecraft. 3D printing’s capabilities go far beyond the capabilities of any other manufacturing method, and those capabilities are being used to build spacecraft that will likely take us to Mars and beyond. It’s an exciting time to be alive, and it’s amazing to be able to follow along as NASA releases updates about the progress of their 3D printed rocket engine, for example. Just look at the power generated by that engine – it’s breathtaking.

It’s not all fire and dazzling displays, however. Sometimes it’s ball bearings and lubricant. Some of the most important parts of building a spacecraft are the dullest, but 3D printing technology is lending itself to the mundane, if vital, aspects of aerospace manufacturing just as much as it is to the more glamorous ones. Take a recent study by ESR Technology and Croft Additive Manufacturing, for example. The study was funded by the Centre for Earth Observation Instrumentation and Space Technology and was part of an effort to identify ways that 3D printing and other new forms of manufacturing could be used to improve problematic mechanical components.

In this case, the problem was the lubricant used in the bearing system. There are a number of issues that arise when using liquid or grease-based lubricant in spacecraft, such as low temperature viscosity and the tendency to evaporate or otherwise escape, potentially contaminating other parts of the spacecraft. To address the problem, ESR and Croft began investigating how the lubricant could be better contained within the bearing system.

Croft specializes in creating complex bespoke industrial parts, like this air filter, using metal additive manufacturing. Using their ReaLizer SLM-250 printer, Croft worked with ESR to develop two concept designs for cages that would better contain the lubricant in the bearing system. Special attention was paid to the challenges presented by a space environment as the cages were designed.

“It is always advised to have several options when seeking to identify a bespoke solution using innovative technologies,” said Neil Burns, director of Croft Additive Manufacturing. “Following the creation and analysis of the two prototypes in this instance, it was deemed more valuable to develop the lubricant retaining cage further. We learnt a number of valuable lessons during this study, the most important of which was in the design process – while AM technology can give greater design freedom relative to conventional machining, it is not without constraints. In terms of next steps, a roadmap has been created to show timescales for exploitation within the space industry and beyond.”

While the lubricant cage is being developed specifically for aerospace applications, it’s likely that the technology used in its development can be applied to issues in the medical, nuclear and other industries. This case study is an excellent example of the way 3D printing is affecting every aspect of manufacturing. While we may not be thinking about ball bearings while watching a rocket launch, their effective functioning could make a lot of difference in the success or failure of a mission.  Let’s hear your thoughts on this story in the 3D Printing and Space Design forum on 3DPB.com.