‘They look alien’: NASA uses AI to design complex spacecraft parts
NASA's Goddard Space Flight Center in Maryland has been using commercially available AI software to design specialized, bespoke parts, called "evolved structures," for its missions. They also look a little "out of this world."
“They look somewhat alien and weird,” Research Engineer Ryan McClelland said, “but once you see them in function, it makes sense."
By starting with the mission's requirements, a computer-assisted design specialist draws the surfaces where the part connects to the instrument or spacecraft; then, the AI software connects the dots to produce complex structure designs in as little as an hour or two.
“The algorithms do need a human eye,” McClelland said. “Human intuition knows what looks right, but left to itself, the algorithm can sometimes make structures too thin," he added.
The evolved structures can tolerate higher structural loads, weigh less, and can be produced in as little as a week. They also need less help from people, which gives designers more time to work on other parts of the mission.
“We found it lowers risk. After these stress analyses, we find [that] the parts generated by the algorithm don’t have the stress concentrations you have with human designs. The stress factors are almost ten times lower than parts produced by an expert human,” McClelland explained.
According to Ryan McClelland, who pioneered the design of these parts, these evolved structures can save up to two-thirds of the weight compared to standard components and reduce the risk of failure.
They are currently used in a variety of NASA missions, including the EXoplanet Climate Infrared TElescope (EXCITE) mission, which is a balloon-borne telescope used to study hot Jupiter-type exoplanets orbiting other stars.
“We have a couple of areas with very tricky design requirements,” Goddard physicist Peter Nagler said. “There were combinations of specific interfaces and exacting load specifications proving to be a challenge for our designers,” he added.
McClelland designed a titanium scaffold for the back of the EXCITE telescope. The IR receiver housed inside an aluminum cryogenic chamber connects to a carbon fiber plate supporting the primary mirror. “These materials have very different thermal expansion properties,” Nagler said. “We had to have an interface between them that won’t stress either material,” he added.
AI-assisted design at NASA could enable the production of larger components in orbit or even facilitate construction on the Moon or Mars using materials found in those locations, advancing "In-space Servicing, Assembly, and Manufacturing" (ISAM) capabilities too.