For the 2008 game FIRST Overdrive, Team 1816 worked on a design concept that involved a fork-like manipulator placed at the front of the chassis. This fork structure, attached to a four-bar linkage, controlled the trackballs, helping to guide and “herd” the balls around the track. The linkage and the fork was able to lift, or “hurdle,” the nearly 10-pound, 40″ diameter ball almost seven feet high, enabling the trackballs to clear the overpass, which is 6’6″ above the playing field. With this manipulator, the robot- known as Zerkit – was able to consistently pick up a trackball, lift it in the air, and drop it over the overpass, a maneuver that proved very valuable during competitions. Three pneumatic cylinders power the entire manipulator, which is made of aluminum bars. The chassis of the robot is powered by four CIM motors, which are geared down through two-speed transmissions. This setup allows us to drive the robot in either low or high gear, depending on whether fine-grained control or raw speed is needed.
Hours of frustration fixing broken parts, combined with some disappointing matches during which Zerkit remained stubbornly motionless (even falling over during a practice match), all made for a rough first day of competition.
Although the design was full of promise, Zerkit didn’t perform as well as expected in the first couple matches at the 2008 Wisconsin Regional. Hours of frustration fixing broken parts, combined with some disappointing matches during which Zerkit remained stubbornly motionless (even falling over during a practice match), all made for a rough first day of competition. Despite these disheartening early setbacks, the team kept working through each problem and ultimately prevailed with Zerkit finishing preliminary rounds with a respectable qualifying record of 5-3. The team’s efforts to reach out to other teams paid off when The Green Machine advanced to the elimination rounds as part of an alliance with Team 2606-Rosemount Robotics, a rookie Minnesota team from Rosemount High School, and Team 74-Team CHAOS of Holland High School, Holland, MI. Even with an exit in the quarterfinals, The Green Machine emerged knowing they’d ironed out most every mechanical setback.
For the first time ever, the team was able to design and build a robot able to perform the most complex task demanded in the year’s game challenge.
Hopes were high going into the inaugural Minnesota Regional, and Zerkit did not disappoint. Despite two early loses to the eventual champion, Team 525-Swartdogs, Cedar Falls, IA, the robot performed admirably, scoring big points as the team won each of the next seven matches to finish the prelims at 7-2. That record made Zerkit the fourth-ranked robot, ensuring a spot in the knock-out rounds. Sadly, our team’s alliance was eliminated in the quarterfinal rounds, due in part to a mysterious power loss suffered by Zerkit at the beginning of a match.
Zerkit lifts a trackball.
When Team 1816 won the regional Chairman’s Award at the Minnesota competition, Zerkit earned one last chance for glory, this time upon the Galileo field at the Championships in Atlanta. Even before the robot entered the preliminary rounds, the team knew it would be hard to advance, as all the teams in the field combined for a staggering 36 regional titles! Given all the competition, the team gave it everything they had, finishing a respectable 4-3, ending in 40th place out of about 80 teams in the Galileo division. Surrounded by remarkable robots from which to choose, The Green Machine was not selected by any of the top-seeded teams to advance to the elimination rounds. Yet, there were other bonuses to take away from Atlanta: For the first time during the 2008 season, operating in competition conditions, Zerkit actually worked properly in virtually all of its matches!
Despite its various operating problems, Zerkit proved to be The Green Machine’s most ambitious and impressive robot to date. For the first time ever, the team was able to design and build a robot able to perform the most complex task demanded in the year’s game challenge. It also marked the first time the team built a robot with a complicated manipulator. Although the robot didn’t win a competition, Zerkit’s design and construction marks a huge step forward for the team.
Game:
FIRST Overdrive is played on a 54 ft (16 m) by 27 ft (8 m) carpeted field, divided lengthwise by a fence median to create a track, and separate the field into Red and Blue zones. The fence is crossed by an overpass marking the red and blue finish lines, and hold the game pieces: 40 in (1,016 mm) diameter inflated balls called “Trackballs”. Two three-team alliances race around the track in a counter clockwise direction while manipulating the trackballs to score points.
The game is made up of two scoring periods. The first 15 seconds of play is the Hybrid period in which robots are autonomous, and may also respond to certain digital signals sent by team members designated as “Robocoaches”, who are stationed at the corners of the track.
The next two minutes of play is the Teleoperated period. At this time, robots are fully radio controlled by the team operators standing at either end of the field.