After a 4-week binge of laser-cutting, wiring, soldering, programming and debugging, it all came down to the moment when a tall man in a dark gray suit took the stage.
"It's time to plaaayyyy some HOCKEY!" he shouted.
Guns N' Roses' "Welcome to the Jungle" blared from the sound system. The crowd, many of them zonked from pulling repeated all-nighters, was in a state of near-delirium.
This was Robockey 2012 - hockey played by wheeled robots. It is the culmination of a notoriously tough engineering course at the University of Pennsylvania - taught every fall by Jonathan Fiene, the man in the gray suit - and it is a wild scene.
For sheer concentration of energy, it would be hard to top Robockey. More than a hundred spectators crammed into an auditorium at Penn's Levine Hall on Dec. 12 to watch the violent clash of machine on machine. They spilled into the aisles, alternately whooping, fist-bumping, jumping up, and yelling themselves hoarse.
Four guys even went shirtless.
"Fraternity brothers," explained Justin Starr, a member of the team that the bare-chested guys were supporting. (Starr himself sported a coat and tie for the occasion. Who says engineers don't know how to dress up?)
The class, a mix of undergraduates and grad students, was divided into 17 teams of three or four people from various disciplines, such as mechanical engineering, computer science or robotics.
Each team built three robots for the double-elimination tournament, which first took place in 2008. The robots were limited to roughly the size of a half-gallon carton of ice cream, and the rink measured about 8 feet by 4 feet.
The robots were fitted with sensors taken from a Nintendo Wii remote, which can detect infrared light. These allowed each robot to tell where it was in relation to a "constellation" of infrared lights mounted on the ceiling, navigating as early sailors did by the stars.
The puck also was studded with infrared lights, so the robots could sense its location. Each bot contained a small computer chip that the students programmed with instructions, such as what path to travel and when, depending on the location of the puck and the goal. Each team had a budget of $120.
Public demonstrations have long been a staple of college engineering curriculums. Students make and break scale-model bridges. They program robots to drive cars or play soccer. And down the street from Penn, Drexel University is a perennial contender in a national competition to make concrete canoes. (Floating isn't the hard part. It's the brittleness.)
Sure, we knew they were good at math and science, but are engineers really defined by a willingness to risk public humiliation?
That is not Fiene's goal.
He does Robockey because it motivates his students, and because he likes the power of learning by doing. Robockey is just a game. But by taking part in the tournament and in other projects over the course of the semester, students get an intense dose of electronics and mechanics that several said made it the toughest course they'd taken at Penn.
Several students said they spent well over 100 hours on the Robockey project alone, wrapping up in the last week with 14-hour overnight sessions in the lab.
Some of the matches last week, consisting of two 60-second periods, were more even than others.
Team 16 jumped out to a quick 4-0 lead against Team 14. Fiene respectfully averted his gaze from the bloodbath.
By the end it was 7-0, one of the goals coming when a Team 16 forward simply drove the opposing goalie backward into the goal. Brutal.
"It was tough," said Team 14 member Rafi Pelles, slipping easily into the role of a cliche-spouting athlete in a postgame interview. "You go out there and you try your best."
He attributed the team's loss to a few bugs in its computer code, along with unspecified issues in the "interface between hardware and electronics."
Before his team's first match of the evening, Nick Parrotta bounced on his feet a few times to warm up, as if he were the one about to step into the rink, not the robots.
Dubbed the Avengers, after the comic-book superheroes, Parrotta's team lost its match. But it finished with a respectable record of five wins, three losses and a tie, counting preliminary rounds. Fellow Avenger Vivienne Clayton was not feeling downcast.
"Adrenaline rush!" Clayton said afterward. "That was so much fun."
Easily tops in the spirit category was Starr's team, dubbed Team 'Murica, as in the faux down-home pronunciation of "America." Like Starr, the rest of the team wore blazers. Starr also wore a red-white-and-blue baseball hat backward, while Tarik Tosun sported a red-and-black-checkered hunting cap.
Their robots had presidential names: Millard Killmore, Martin van Bruisin', and Grover Cleaveland.
There was substance to go with the flash. Many teams' robots got stuck in a fierce scrum from time to time, wheels spinning madly. But if one of 'Murica's robots got stuck, it was programmed to back up and allow its teammate to attack from a different angle.
"It was beautiful to watch," Fiene said later.
Another strong contender was Team 8, whose members were clad in neon-yellow T-shirts. They started each match by placing their three robots in single file, so the wheeled combatants could plow forward as one.
"That's our train formation," said team member Ian Rafter.
It was a good strategy, until they met Team 10 in the finals. That team consisted of Wenbin Zhao, Daniel Chabolla and Sean Gowen, all seniors in mechanical engineering.
Designing the robot required making decisions, and one of the biggest was selecting a motor. Speed or brute force? Claude Giroux or Chris Pronger?
Team 10 opted for speed.
"Our strategy was, if we got the puck first, we're not going to have to worry about being pushed around," Gowen said.
They won the championship, beating Team 8 by a score of 6-5.
But there was no time for celebration, Gowen said:
"We had a report due the next day for another class."
Explore further: Robots Playing Shuffleboard (w/ video)