Rockets, Research, and Rovers
|Clay Penney '19 and Col. James Squire travel to Highland County Nov. 3 to test their rocket prototype.|
LEXINGTON, Va., Dec. 13, 2018—At VMI, seeing cadets set and achieve big goals is almost an everyday occurrence. But Clay Penney ’19 and his mentor, Col. James Squire have set a goal big enough to be called audacious: to succeed in a rocket-launching competition that no entrant has ever completed successfully in the decade-plus history of the competition.
On March 30-31, Penney will launch his 11-foot-tall homemade rocket in Culpeper, Virginia, as part of the Federation of Galaxy Explorers’ Mars Rover Competition. For Penney, an electrical and computer engineering major, the rocket project is the basis of his Institute Honors thesis.
To meet the requirements for full completion of the competition, contestants must launch a rocket to at least 1,000 feet, with an autonomous robot contained inside the rocket at the time of launch, and then deploy the robot for a safe landing.
Once the robot has landed, it must travel at least three feet and wait for a command from a small handheld wireless controller. Upon receiving the command, the robot is to collect between 5 and 25 grams of soil. After that, the robot is to take a picture of the area from which the soil was collected, and then its work is done. The work done is meant to simulate that accomplished by the actual Mars Rover.
Completing the Mars Rover Competition sounds simple. But as Col. Jim Squire, Penney’s adviser, explained, nothing could be further from the truth.
“It’s freakishly, freakishly difficult,” said Squire, professor of electrical and computer engineering. “No team in the history of this competition … has ever managed to not get disqualified at some point.
“There’s just so many things that can go wrong on a rocket launch,” Squire continued. “Even the big boys like NASA have had problems with their Pathfinders.”
Because every team that’s ever attempted the competition has been disqualified, Squire explained, the “winner” is the team which accumulates the most points by coming closest to reaching all of the goals. In years past, the winners have been schools with big aerospace programs such as the University of Alabama at Huntsville and the University of Texas at Arlington. Some years, no one enters the Mars Rover competition at all, Squire noted, likely because potential entrants realize the depth and breadth of the challenge.
Penney, though, had the wisdom to know he’d need a test launch—and he and Squire completed that in early November at a launch site in Highland County. At the test launch, some things went well, and some did not.
At first, it was a picture-perfect launch as 450 pounds of thrust blasted the rocket skyward. At 1,300 feet, the rocket reached apogee—the highest point of its arc—and the craft’s flight computers recognized the time was right to set off the black-powder charges that would deploy the robot, attached to a parachute to assure its safe landing.
That’s when things went wrong. “[The rocket] broke apart in ways it was supposed to, and ways it wasn’t supposed to,” said Penney. Because some screws gave way when they shouldn’t have, the force of the parachute yanking away pulled the avionics bay—the portion of the rocket housing the flight computers—away from the main body of the rocket. The avionics bay landed a mile and a half from the launch site, and it was up to Penney, a former cross-country runner, to retrieve it in a speedy fashion.
Not surprisingly, Penney found his creation caught in a tree. But a red, white, and yellow parachute isn’t too hard to find. “The VMI colors really stood out in the tree,” said Penney.
The robot wasn’t part of the test launch, though a prototype of it was supposed to be. “We ran into a size constraint at the last minute,” Penney explained. “The robot was about a quarter-inch too wide to fit correctly into the tube.”
They’d measured, of course, well aware that an eight-inch diameter rocket is a very small space. But there was a problem neither Squire nor Penney had thought of—leaving room for the parachute as well as the robot.
“There’s odd things like that that even if you’re trying to test along the way, you don’t think of,” Squire commented. “That’s why we did the test [launch]. There’s too many variables to hit them all perfectly the first time through.”
Before the March competition date, Penney plans to strap the rocket together internally so it can’t break apart again when the parachute deploys.
“While it didn’t go 100 percent perfectly, we can have it flying within a week and have it better than it was before,” he said the day of the test launch.
“I wouldn’t have this opportunity without VMI or Col. Squire, so I’m just grateful for that and the Honors Program,” Penney added.
Funding for Penney’s project has come from the Wetmore Fund, the Department of Electrical and Computer Engineering, and the Jamison-Payne chair in electrical and computer engineering, which Squire holds.