NASA 3D prints metal “space fabric”
NASA engineers go beyond traditional 3D printing techniques and print both the geometry and the function of these "space fabric" materials.
Raul Polit Casillas has always been intrigued with how materials are used for design. As a systems engineer at NASA’s Jet Propulsion Laboratory in Pasadena, California, Polit Casillas is now able to design advanced woven metal fabrics for use in space.
These metal “space fabrics” can be used in a wide variety of applications including large antennas or other deployable devices, because the material is foldable and the shape can be altered quickly. However, engineers believe the fabrics could also potentially be used in astronauts spacesuits as well as insulate spacecrafts.
Polit Casillas and colleagues created this chain mail-like prototype using advanced 3D printing techniques.
“We call it ‘4-D printing’ because we can print both the geometry and the function of these materials,” said Polit Casillas. “If 20th Century manufacturing was driven by mass production, then this is the mass production of functions.”
Because fabricating spacecraft designs can be extremely complex and costly, adding multiple functions to materials at different stages in the development makes the process worthwhile, says Andrew Shapiro-Scharlotta of JPL.
“We are just scratching the surface of what’s possible,” Shapiro-Scharlotta said. “The use of organic and non-linear shapes at no additional costs to fabrication will lead to more efficient mechanical designs.”
There are four essential functions in the space fabrics: reflectivity, passive heat management, foldability and tensile strength. One side of the fabric reflects light, while the other absorbs it, acting as a means of thermal control. It can fold in many different ways and adapt to shapes while still being able to sustain the force of pulling on it.
The team hopes to eventually manufacture the fabrics in space. Polit Casillas explains that one day astronauts might be able to 3D print materials as they are needed. Reusing materials to build new materials in an environment where resources are limited is critical to success.
However, it’s critical to think about new forms. Print a single plate of aluminum, and it has limited functionality. Print the same plate using a heat-radiating design, and suddenly it’s more useful. Spacecraft housing could have different functionality on its outsides and insides, becoming more than just structural.
Polit Casillas is working towards more design-based thinking when it comes to the way spacecrafts and space materials are engineered.
“I can program new functions into the material I’m printing,” Polit Casillas said. “That also reduces the amount of time spent on integration and testing. You can print, test and destroy material as many times as you want.”
Separate from his space fabric research, Polit Casillas co-leads JPL’s Atelier, a workshop that does rapid prototyping of advanced concepts and systems. This fast-paced, collaborative environment develops different technologies and infuses them into new concepts, one of which is 4-D printing.