Nightingale Middle School

Sumobot Rules

SumoBot Rules - Nightingale Middle School


1. The competition dohyo (combat area) shall be a circle with a 1 meter diameter. The competition area shall be within the inner plane of the circle.
2. Two start lines shall be placed 5cm from the center point of the dohyo (10cm apart). At the start of the completion, every part of the SumoBot must be behind that competitor’s start line. (The SumoBot may be placed any distance from the start line, as long as no part of the Bot extends over the line marking the combat area.)
3. The maximum mass of the SumoBot is 800g. The maximum length when in the starting position shall be 30cm.
4. Building materials are limited to those authorized by the First Lego League competitions.
5. At the judge’s “Start!” command, competitors shall initiate their programs but may not touch the Bot any time after.
a) Winner shall be the first SumoBot that forces its opponent outside of the competition area. This shall be defined as any part of the Bot touching the playing surface outside of the competition area, or touching any part of the vertical wall near the circle. A Bot going out of the competition area under its own impetus shall also be declared the losing Bot.
b) Each bout shall last a maximum of 90 seconds. In the event of the time limit being reached before a Bot is forced out, the Bot with the lower mass shall be declared the winner.
c)Preliminary seeding shall be determined by the mass of the SumoBot, low mass shall have the highest seed, and continuing in ascending order of mass.
d) Preliminary rounds shall be best 2 of 3 bouts. Championship round shall be best 3 of 5.
e) 90 seconds between bouts, 5 minutes between rounds. Teams may use the between-round time to test any aspect of their SumoBot.
6. SumoBots may be repaired (returned to their original design) after a bout. Modifications (including programming modifications) are only allowed between rounds. SumoBot must be re-weighed after any structural modification.
7. The Head Judge shall be the final arbiter of any disputes.


1) Starting Positions redefined:
a) Four starting blocks will be established within the dohyo. Each block will be a rectangle 20cm x 30cm (corresponding sides are parallel), with the center of each box at the center point of each quadrant of the circle.
2) In the preliminary rounds: At the start of the first bout, SumoBots will be placed completely within the starting block on the player's left. At the start of the second bout, SumoBots will be placed completely within the starting block on the player's right. At the start of the third and final bout the low mass Bot will have choice of left or right.
3) In the championship rounds the pattern will be left-right-left-right-low mass choice.