Photo:Andy Hospodor

CLICK HERE for a slide show of the robot competition

The Activities and Recreation Center on the UC Davis campus is filled with the sounds of electric motors, ripping carpet, clanging metal, and screaming fans. It's 31 March 2007 at the FIRST (For Inspiration and Recognition of Science and Technology) Robotics' Sacramento/Davis regional competition [Click here to read the second story in this series.], and a lone all-girl team is in the semifinal alliance, hoping to prove they're among the best of 39 teams. Says co-captain Alexis Morgester, a.k.a. Hyperdrive: "We don't get intimidated by the boys-we're three years ahead of them mentally."

The Fembots of St. Francis High School, in Sacramento, had pinned their hopes on Charlie the Robot, and nothing was going to faze them. When inspectors declared the earrings they had made from robot parts unsafe, the Fembots took them off. "No more earrings in the pits," proclaimed team safety captain Lisa Marie "WireS" Williams. "We're tired of being runner-up for the safety award," she said. They gave the baubles to passing robo-girls from other teams and to a middle schooler who might someday join the Fembots. (Fembots spend a lot of time recruiting: during the regional competition, members regularly led invited groups of middle schoolers on tours of the pits and playing field.)

The Fembots started designing Charlie the Robot in January 2007 after a thorough examination of the 2007 rule changes, which led them to divide robotic functions into the "must-haves" and the merely "nice-to-haves." They started working right away on the must-have manipulator that would place scoring rings on the highest levels of the rack. They left the nice-to-haves until later. Some, such as ramps to lift other robots, never got done at all.

St. Francis High School emphasizes humanities rather than technology and so, unlike many other teams, it had no access to CAD systems. Instead, the Fembots used graph paper-and lots of it. A few sessions with Gary Blakesley and John Kornylo, engineering teachers who served as their mentors, finalized an efficient design. Then the girls split up into subteams to build, program, animate, and finance the project. And they also did their own public relations.

The Fembots created posters of each system: electrical, pneumatic, software, and drive train. They labeled the posters with instructions on how to debug the systems, so that any Fembot in the pits could correct any known problem and bring the robot back online. On their own, they had figured out the classic elements of engineering-design, documentation, and debug/test instructions.

In the 2007 version of the game, each team starts with nine pool rings on the field and nine behind the human players. Robots place rings on a scoring rack in the center of the field to earn a point, and any team that can use a robot to lift a partner robot 30 centimeters above the field scores a bonus of 30 points. During qualification matches, the members of the teams allied with the Fembots hurriedly tossed rings over the wall, exposing a design weakness in Charlie: the robot couldn't pick up rings from the ground but instead had to be hand-loaded. The Fembots landed in last place.

That could have been the end of the story, but the coed fourth-seeded alliance of TKO from Archbishop Mitty High School, in San Jose, Calif., and the Raging Seabiscuits of San Ramon Valley High, in Danville, Calif., noticed that Charlie climbed ramps easily. They realized that they could count on the robot to take a ride up in the air to score bonus points. The Fembots joined that alliance, and the group easily advanced to the semifinals with wins of 62-18 and 45-4.

In the semifinals, the Fembots' alliance lost the first game 128-64. In the second game they went on the defense, counting on lifting robots in the end for bonus points and a win. The strategy worked, and they won the second game 45-32, with one robot fully lifted, for 30 points, and one partially lifted, for 15 points. As the clock ticked off the last seconds of the third game, the Fembot alliance already had their robots in the air for what looked like a 62-32 win. With the crowd cheering wildly, but before the referees entered the field to measure the heights, something went horribly wrong. Pressure dropped in a pneumatic pump holding the robots airborne and they slowly fell to the ground, dashing the Fembots' hopes of victory. Fembot Jenny "AutoSaw" Cheng quotes her father: "We lost a game that we had already won."

The alliance that beat the Fembots went on to lose in the finals, after a notable display of gracious professionalism. One of the robots in the competing alliance broke a chain and three robots versus two would be an easy victory. But the opposing alliance lent the team a spare chain-nobody here wanting to win by default-and the alliance of the Wildcats of Woodside [Calif.], the Spartan Robotics of Corvallis [Ore.] High School, and the Danvillans of Monte Vista High School, Danville, Calif., won the final game of the match on a borrowed chain.

Look for IEEE Spectrum's fourth and final report on the FIRST Robotics Competition, from the national championship in Atlanta's Superdome later this month.

For Robot Girls Part 4, see "Robo-girls Take On the World"