Sumo Mega Rules

Change log 21.04.2018

Blade break: the referee may decide to give timeout between matches for changing the blade.

General information

The matches will take place between two teams, each team having one or more members. During the battles only one member may approach the ring, the other team members must watch the match from the public. According to the rules, the teams will compete in a Dohyo (sumo ring) with an autonomous robot, own creation as specified in Section II.

The referee designate the start of the match with the remote control, and it continues until one of the two robots get 2 points "Yuhkoh". The referee designates the winner.

The implementation of the robots.

The building of thr robot

It accepts any design which does not fall under the limitations of chapter II.ii.

Maximum dimensions: the robot must fit in a square 20 cm x 20 cm.

The maximum mass of the robot must not exceed 3.00 kg.

The robot can be extended after the start. The robot is not allowed to separate into two or more pieces. It must remain in a single centralized robot. The robots that do not respect these rules will be disqualified.

Screws, nuts, washers or other parts with a mass less than 5 grams, who will fall will not cause the loss of match

All robots must be autonomous. It can be implemented any control system, while it is inside the robot and does not interact with external control system (human, machine or another).

Limitations of the robot.

For safety reasons the robots must be equipped with a sensor off (IR) which will be operated by the judges. When the referee will send a stop signal, the supplying of the engines must be cut. The sensor will be used also to power simultaneous both robots, by the referee. The specifications for the sensor on/ off IR are in Appendix.

The devices jamming against opponents such as radiation sources to saturate IR sensors, ultrasonic transmitters or other devices with similar effect are strictly prohibited.

There are not allowed components of the robot that can destroy the playing area. Do not use components intended to destroy the robot of the opponent. The thrusts and the normal blows specific for a sumo match, are not considered intentions for destroy.

Devices that can store liquid, powder, gas or other substances what can be thrown into the opponent are prohibited.

Any devices that throws flames are not allowed.

The devices who throw objects towards the opponent are not allowed.

The sticky substances what can improve the traction are not allowed. The wheels and other components of the robot, which are in contact with the floor, not must be able to raise and support a standard A4 sheet (80mg / m²) for more than 2 seconds. The robots will be check in the approval phase and it can be re-verified at the request of the referee in any stage of the competition.

The devices for increasing pressure on the surface, such as vacuum pumps or magnets / electromagnets are allowed.

The blade of the robot and the expansion cannot be white.

It is not allowed to use flags on the robot.

Dohyo (sumo ring)

The inside of the ring

The inside of the ring is defined as the playing surrounded surface, but which includes the white line. Any area outside the ring will be called outside the ring.

The specification of the ring

The play area is defined as a steel disk with thickness of 3mm with black colour, with a diameter of 154cm.

The ring is placed on a metal support and it is lifted up to 5 cm above the ground.

Around the ring there is a space for not to disturb the robots sensors.

It's allowed the tolerance of 5% in the construction area of the contest.

The outside of the ring

There is a safe space outside the ring. This space it can be by any color, can be of any material and may have any shape. This zone with the ring in his center it will be called the zone of the ring. The zone it certainly is a square with the side of 4 meters.

Course of the match

A match consists of three rounds, each lasting a maximum of 3 minutes with the possibility of extending the time by referees.

The first team that wins two rounds or receives the first two points "Yuhkoh" until the end of the time will win the match. A team receives one point "Yuhkoh" when they win a round. If the time limit is reached before a team receiving two points "Yuhkoh" and one team received an "Yuhkoh", the team with a point will win.

If the game is not won by any team in limit time, an additional round will be played. After exhausting all alternatives, the winner of the match can be decided by arbitrators by lot or other criteria established by the arbitration panel.

If the robots crashes they will be stopped after 2 seconds and the game will resume. If after the 2nd attempt the robots crashes again, it will be given equality.

If one of the two robots are not going to the start, there will be a restart. If neither after restart same robot does not work the match will be won by the functional robot. (Participants are required to notify the referees at the start of the match if the robot has a sequence that does not start after the received signal, who not to be confused with a malfunction).

The progress of the contest

The robots will be divided into groups according to the number of participants. The contest will run in this system, groups / quarters / semifinals / final to allow as many rounds of play for each robot separately. Each match goes in this system the best of three rounds and will be supervised by two referees (one referee and one assistant referee), excepting the final, where the game will be played in the format ''the best of 5 rounds''. The referee's decision must be unanimous and finals, and contesting his decision brings the participants disqualification from the match.

Throughout the competition a team is allowed to have two interruptions for reprogramming during matches, 5 minutes each (2 outages throughout the contest). Other breaks are only allowed to mechanical problems and only with the referee approval, than 5 minutes each. This rule is only applied when performing a match. Outside the matches, the reprogramming and the changes are allowed. Teams are required to be to the start in maximum 1 minute of receiving the request, otherwise they will lose the match.

After approval, all teams remain in the competition hall. The teams can leave the room only for repairs. If a team leaves the room for repair, it must turn during specified by the referee. If the robot is not present at the first call lose the match.


Each team will have to pass the homologation stage to participate with the robot in contest.

Stages of the homologation process are:

1. Verification of the dimensions of the robot by placing a box/frame of 20.3 x 20.3 cm , bottomless, over the robot.

2. Weighing the robot on a digital scale. The maximum recorded weighing should be of 3.005 kilograms.

3. Will be Checked operation of the IR sensor to start and stop the robot.

The robot will not be retained after homologation.

After homologation of all teams remain obligatory, in the examination room.

Start, Stop, Restart, End of match

The start position of the robot

At the Instructions of the referees, both teams are approaching the ring to put robots on the contest area. A cross with two opposing arrows placed in the middle, divides the sumo ring into four quadrants . Robots always must be placed in two opposite quadrants. The robots must be placed at the edge assigned quadrant. Robots must cover at least partially the white edge. After positioning the robots it's removed the cross, and then robots can not be moved anymore.

Sumo Mega fig1


The start is given by the referee in each round using a remote control that sends a signal to the robot, where among they will begin immediately without any delay. The details of the sensor can be find in annex.

Stop, Continue the match

Start, interruption or continuation of the match are announced by the referee.

End of the game

When the referee announces the end of the game, the two teams raise their robots from the ring.

The time of the game

The duration

A match will be played over 3 minutes. He will start and end at the referee's command.


An additional match if requested by the referee, it will take up to 3 minutes.

The score

An "Yuhkoh" will be granted when:

1. The robot of a team forces the opponent to get out of the ring by pushing or lift. The robot of the opponent is considered defeated if touches any part or components, which is placed on the outer surface of the ring.

2. The robot opponent gets out of the ring from any reason.

3. The opponent robot breaks, without possibility to continue the round and the team representative announce this.

When determining the winner falls to the referees after exhausting specific criteria Sumo competition, the following aspects are taken into account:

1. Quality of the construction and programming of the robot.

2. Penalty points accumulated during the match.

3. The attitude of the team during the match.

Rematch conditions

The game is stopped and the round is resumed in the moment when:

1. The robots revolve around each other, without visible progress for 10 seconds. Robots are stranded more than 2 seconds. If it is not clear that the robot progressing, the observation time can be extended up to 30 seconds.

2. The both robots are moving without making any progress, they stop (while) or they stay stopped for 10 seconds without touching themselves. However, if a robot stops moving, first, after 10 seconds will be declared without fighting initiative. In this case the opponent will receive an "Yuhkoh" even if he stopped. If both robots are moving, but progress is not clear, the referees may extend the observation time to 30 seconds.

3. If both robots touch the outer surface of the ring in the same time and it can not be determined which robot reached the outer surface first, the round will be replayed.

Repairs, modifications, sudden interruption

If a robot is damaged during a match, the referee shall allocate an interval of 1 minute for repairs. This range may be extended up to 5 minutes by the organizers. Repairs will be supervised by an assistant referee to avoid change of unapproved other robot modules.

If a robot can't be repaired within the specified interval, the match is won by the opponent robot, and the team with the broken robot can continue the repairs until their next match and they will be supervised by a referee or a member of the organizing committee.

Replacing the defective parts can be performed, and the batteries can be charged during the competition, if it’s necessary.

Accidents during a match

The request to stop a match

A contestant can ask for the end of the match if he/she is injured or the robot sustained a damage and cannot continue the game

Unable to continue the match

When the game cannot continue due to injury or because of damage to the robot, the contestant who causing the injury or malfunction of the robot will lose the match. If can not decide who is guilty then who will ask to stop the match will be declared the loser.

The time required to care / repair

If the game can continue, in case of injury or damage, will be decided by arbitrators. The decision must be taken within 5 minutes.

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