As the prime contractor on NASA’s suit program, ILC partnered with the University of Delaware’s Center for Composite Materials to design and manufacture space suits that can hold up to the red planet’s harsh environment: average temperatures of minus 81 F, a gravity just 38 percent that of earth’s and an atmosphere that’s mostly carbon dioxide.
“The genesis of our partnership with ILC on this project was matching their expertise in soft composite materials with ours in hard-shell composites to do something that hadn’t been done before and meet the requirements for the Mars space suit,” says Jack Gillespie, an engineering professor at the University of Delaware and director of its Center for Composite Materials (CCM).
NASA had very specific requirements for fit and function, one of which related to the low gravity on Mars. During planetary exploration, astronauts could fall onto hard objects. “The composite components subjected to that impact loading could not leak and had to retain vacuum integrity,” says Gillespie. To help protect the astronauts, NASA opted for lightweight, hard-shell sections on the torso of the new space suit, called the Z-2. Composites are utilized in three areas: the hard upper torso (HUT) covering the chest, the brief around the waist and upper legs and the entry hatch, which is a backpack mounted to the back of the HUT.
“The HUT had to have articulating components so the astronauts could move around, and the components had to be integrated into vacuum-tight joints when you assemble the space suit’s soft components with the hard ones,” says Gillespie. “And of course, we had to find a way for the astronaut to get in and out of the suit as well.”
The HUT, brief and hatch, which were designed at the CCM’s Applications & Technology Transfer Lab (ATTL), utilize IM 10 carbon fiber as the primary reinforcement. “We did a lot of internal work looking at representative impact loading of candidate laminates to test and prove out the performance,” says Gillespie. “That led to hybridization of the carbon fiber with some strategically-placed glass. Ultimately, that turned out to offer the minimum weight solution to survive the impact load.” The high-modulus, woven fabric carbon fiber is used in tandem with S-glass and an epoxy resin system.