The game is played by two alliances, red and blue, of three teams each. No alliances are ever purposely the same. When the alliances are picked it is totally random, and you can be on either red or blue alliance. Each team has bumpers made from cloth and pool noodles, with their numbers on it, one set painted blue and the other red. Each team will use certain bumpers according to the color alliance they will be on.[11] Alliances compete in 135-second matches to earn as many points as possible by scoring basketballs into hoops or by balancing tilt bridges.[11]
The field is a carpeted area 27 feet by 54 feet[11] designed to mimic a basketball court.[12] At both ends are the driver stations and an array of basketball hoops.[11] There is one low hoop, two middle hoops, and one high hoop.[11] Across the narrow dimension of the field a 4 inch high wall, along which are placed three tilting bridges at a height of 12 inches.[11] The bridges at the edges are color-coded for each alliance, and the center bridge, called the Coopertition bridge, is available for both alliances.[11]
Basketball hoops at one end of the field
Bridges at the beginning of a match
The field at the beginning of a match at the West Michigan district
Robots start a match in contact with their key, the semicircular plastic area approximately at the free-throw line.[11] Each match lasts 135 seconds[9] and is divided into two portions: Hybrid mode and Teleoperated (Teleop) mode.[11] During Hybrid mode, two robots on each alliance have to act autonomously, while the third may be controlled by means of a Microsoft Kinect or act autonomously.[8][11] During Teleop, all robots are controlled by human drivers.[11]
At events, there are two types of matches: qualification and elimination.[11] Robots compete in qualification matches to determine seed and who will compete in the elimination bracket.[11]
Throughout a match, teams can score points as follows by scoring basketballs into hoops:[11]
Hoop
Hybrid
Teleop
Top row
6
3
Middle row
5
2
Bottom row
4
1
At the end of the match, points are scored for balanced alliance bridges, but not the Coopertition bridge.[11]
Number of robots balanced on bridge
Qualification match
Elimination match
1
10
10
2
20
20
3
20
40
Balancing the Coopertition bridge with a robot from each alliance earns each alliance 2 Coopertition points toward their qualification seed and the Coopertition Award.[11][13] If the two robots do not balance the bridge, 1 Coopertition point is awarded.[11]
Robots must not exceed horizontal dimensions of 28 inches by 38 inches, begin each match less than 60 inches tall and never exceed 84 inches in height.[11] An allowance is made for one protrusion of no more than 14 inches (so long as this protrusion is retracted at the start of the match).[11] Discounting the battery and protective bumpers, the robot cannot exceed a weight of 120 pounds.[11]