Tournament Brackets

There are many different ways to run robot combat tournaments. Given the time and investment most builders have in their robots, they prefer tournament systems that guarentee them more than a single match but in some cases it isn't possible to hold that many matches.

Choosing a format means balancing the number of fights each robot gets, the time available, and how many robots need repairs between matches. Under the SPARC Match Rules, round robin is the standard for classes with 5 or fewer robots and double elimination for 6 or more, and robots get a minimum turnaround time between matches (20 minutes for robots of 150 g to 6 lb, 30 minutes for heavier ones). Whatever format an event uses, it should be announced in advance.

Tournament Tools

• Challonge – free online brackets, widely used by local events
• BracketHQ – simple free bracket maker
• TrueFinals – online brackets with live updates; used by NHRL[1]
• start.gg – tournament platform from the esports world, with registration and brackets

Many events also post brackets on screens or a website so builders can see when they're up next.

Bracket Types

Double Elimination

Every robot starts in the winners' bracket; a loss drops it to the losers' bracket, and a second loss eliminates it. The winner of the losers' bracket must beat the winners' bracket champion twice to take the title. The SPARC standard for larger classes, since every robot is guaranteed at least two fights.

A modified double elimination treats the final as a single match, so the losers' bracket winner only needs to win once. It saves time at the end of the day.

Single Elimination

One loss and you're out. Fast and simple, but half the field only gets one fight, so it's mostly used when time is short or after a qualifying round.

Round Robin

Every robot fights every other robot in its class, and the robot with the most wins is the winner. Ties are decided by the result of the match between the tied robots, or a judged rumble if more than two are tied. A double round robin has each pair fight twice. The SPARC standard for small classes; it gives lots of fights, but the number of matches grows quickly as more robots enter.

Swiss

Robots are paired each round with opponents who have similar records, for a set number of rounds, without anyone being eliminated. Every robot gets the same number of fights, and the strongest robots rise to the top. Swiss rounds are sometimes followed by a short elimination bracket for the top robots. Swiss events can mean many fights in a day, so bring plenty of spares and batteries.

Ante Up

(Description needed – please add one if you know this format.)

See also

• Events – running and finding events
• Pit Kit and Event Checklist – preparing for an event
• Judging Systems