MTSU lunar rover team banks on new airless tire design at NASA event

MTSU Experimental Vehicles Program lunar rover team members hope a new airless tire design and parts assembly will lead to a 'wheel of fortune' at this year's NASA Human Exploration Rover Challenge.

Because of new competition rules regarding tires, recent MTSU graduate Thomas Kenney's design and the machine shop work by junior mechatronics engineering major Kelly Maynard and others may keep the MTSU engineering technology entry among the elite in the international field competing in Huntsville, Alabama, Friday and Saturday, April 8-9, after a best-in-U.S. finish in 2015.

The event is held annually for university and high school teams to encourage research and development of new technology for future mission planning and crewed space missions to other worlds.

One of the early teams to compete in the college and university division April 8, MTSU drivers Aaron Greenberg and Ailime Freitas maneuvered the course in 7 minutes, 15 seconds. They incurred two penalties, resulting in two minutes added to their time, but they still led the nearly 90-team field by midmorning.

"They had a gear issue, but they know how to fix the problem," said Dr. Saeed Foroudastan, program adviser and associate dean for the College of Basic and Applied Sciences. "I'm really proud of them. They did a super job (in Friday's run), but I believe Saturday we'll do very well and it will go all the way (without stopping)."

Before leaving for Huntsville, co-captain Zach Hunter, a senior mechatronics engineering major from Knoxville, Tennessee, said he thought "they should be extremely successful" this year, primarily because of the new, white-ribbed wheels.

"It is an aesthetically pleasing wheel," he said. "They travel through different media without failing. I think the NASA judges will like it. I'm excited about the wheel technology section."

Kenney is credited with the new design that was "inspired by a cross-spring pivot mechanism" and the idea coming from "Bridgestone having a similar design."

Maynard, in her second full year with the Experimental Vehicles Program and lunar rover team, receives the bulk of the credit for the machine shop work.

"They look professionally made," she said, "especially the way we designed the tread."

The tires are made with ultra-high-molecular-weight polyethylene, or UHMW. There are 360 individual UHMW nubs on each of the six wheels (a prototype, four competition tires and a spare). Each nub can be switched out.

"The major challenge was the assembly," Kenney said. "In all, 30 people were involved in the assembling of the tire and rib section."

Knowing what they encountered a year ago, Maynard likes the 15-member team's chances.

"My goal is for us to be first internationally, not just first in the U.S.," she said with optimism.

Foroudastan said junior Brad Hobbs, a mechatronics engineering major, would drive during the April 9 competition run.

Murfreesboro's Central Magnet School and Coffee County Central High School in Manchester, Tennessee, both fielded two teams competing in the high school division.