Students' robot solves Rubik's Cube in 15 seconds

A Rubik's Cube has been sitting on Joe Ridgeway's shelf since he was a child, but it wasn't until he was studying at Rowan University that he fully embraced its challenge.

Before long, he was determined to memorize faster ways to crack the puzzle. Then, he decided he wanted to go faster.

In a project that started in a Rowan course, Ridgeway and Zachary Grady, both senior electrical and computer engineering (ECE) majors, have built a robot that solves the cube in 15 seconds.

The Rubik's Cube-Solving Robot, a year in the making, has earned the duo more than 17,000 hits on YouTube and a congratulatory note from Erno Rubik himself. And though it's not yet official, they are confident, based on their research, that the robot is the fastest of its kind.

"They invested a lot of time in this, probably more than they got their credits for," said Philip Mease, an ECE technician and adviser.

The project sprang from Rowan's engineering clinic, in which the students received an open-ended call to take state-of-the-art Siemens hardware and, as Mease said, "do something cool."

The resulting rig features a smooth, metallic fixture that attacks the suspended toy with laserlike efficiency. Powered by a special camera, a computer brain, and a donated Siemens programmable logic controller (PLC), a square cup works with a spinning base to manipulate the cube's colored sides with noisy, rapid cranks.

The robot wastes little time - after 17 moves, it twirls the descrambled cube in a modest celebration.

Ridgeway, 21, and Grady, 22, made the machine from scratch, they said, working under the guidance of Mease and ECE chair Shreekanth Mandayam and with mechanical-engineering help from graduate student Karl Dyer.

Mandayam said he was initially thrown off by the project and was surprised by the public reaction.

"I just absolutely could not believe the amount of interest it has gotten, the amount of hits that we have gotten," he said.

Siemens' PLC, the unassuming gray box behind the business end of the machine, is the same type of equipment that directs manufacturing robots, Mease said.

While assembly lines are a major part of industrial automation, they can be less than exciting to college students, the advisers said. The Rubik's Cube-centered project enlists the same set of skills, according to Mandayam, but the elements of pop culture and competition that the cube brings into play make it much more appealing.

"The difference is night and day when you get students that are internally motivated to solve something," Mease said.

The strategy Ridgeway and Grady developed was markedly different from their competitors', and YouTube is host to many of those. The much-viewed Rubot II, built in Ireland, turns the cube with two humanlike hands, plays "robot-y music," and speaks to its audience.

The Rowan robot may be stripped-down, but it cuts the Rubot's time in half. Ridgeway and Grady abandoned the human method, instead setting the cube on its corner for optimal maneuverability.

"I think that's really the main difference between ours and the competition," Grady said.

According to Frank Lee, a professor of computer science at Drexel University, this approach follows a more modern focus on building robots to do a job in the best way possible, regardless of how humans do it.

The Rowan project exemplifies the benefits of student-centered learning, he said. He added that the robot shared a fundamental similarity to higher-profile pursuits, such as the Japanese effort to build robotic aids for the elderly.

"They have the same DNA, which is trying to solve problems in the world using automated technology," Lee said.

The engineering duo at Rowan continue to improve their problem-solving machine.

Although they are to graduate in May, Ridgeway and Grady have further hopes for their creation. They would like to verify the record with Guinness, demonstrate the robot on Conan O'Brien's late-night show - Mease is a fan - and, of course, make it even faster.

Grady hopes a new team will pick up the challenge where his leaves off: "Five seconds? That would be amazing."

To see a YouTube video of the robot at work, go to http://go.philly.

com/rubikEndText