Professor works to design better tires for Mars

Heather Oravec, research associate professor stationed at the NASA Glenn Research Center, holds a spare aluminum tire for the Mars Curiosity rover in the Simulated Lunar Operations Lab in Cleveland on Sept. ,9, 2019. Oravec's research in extraterrestrial soil mechanics and extraterrestrial surface mobility helps in developing new tires for off world vehicles and rovers. (Mike Cardew/Akron Beacon Journal via AP)

CLEVELAND (AP) — Nine years ago, NASA’s Mars rover Spirit sent its last signal from the Red Planet.

The rover had ground to a halt on the sands of Mars, its tires sinking and spinning futilely in the fine-grained particles.

“Spirit got stuck (and it) ended its mission,” said Heather Oravec, a mechanical engineering research associate professor at the University of Akron who is contracted to work full time at NASA Glenn Research Center in Cleveland.

Spirit was willing, but its tires were weak.

Oravec wants to make sure what happened to the plucky rover doesn’t happen to its successors.

Part of her role at NASA is testing tire designs for future rovers using simulants — artificial “soils” with properties similar to Mars or lunar terrain — to test new tire designs.

Oravec is an expert on extraterrestrial dirt, having developed a simulant called GRC-1 for her doctorate thesis. Although she and her colleagues have no Mars samples to work with, many of the properties of different Mars terrain are known.

They vary.

The smooth, solid surfaces aren’t a problem. It’s the sand and rocky conditions that pose the problem. That’s where Oravec, as part of the Surface Mobility Team, comes in.

Using simulants, tire prototypes and a Carnegie Mellon designed rover, they test the sands that sunk Spirit in “some of the worst-case conditions,” Oravec said.

Oravec is testing a new tire design using a nickel-titanium alloy she calls “memory metal.” It is competing with current designs that have taken a beating on the rough Martian surface.

“Curiosity has a significant amount of holes in (the wheels),” Oravec said.

She’s confident the “memory metal” design will get the ultimate test on the Red Planet.

“This new design is going to be on future missions,” she said. “It’s lighter weight, can take (heavier) loads.”

It also has an easier time navigating rocks and tough terrain that have damaged Curiosity’s wheels.

“The new design envelops the rocks,” she said. “(It) remembers what its original position was.”

Oravec isn’t the only University of Akron presence at NASA Glenn. According to public affairs officer Jimi Russell, 106 current employees at the center have at least one degree from UA. The center also had four summer interns from UA this year.

Oravec may be the most grounded UA presence at NASA Glenn, but she has her hands in the air, splitting time between simulants and space seals.

In her other role, she helps develop docking designs for the International Space Station.

“Dragon just docked with one of our seals,” she said.

A manned NASA spacecraft, called Orion, is in the testing stage and she will help design the seals that connect it to the ISS.