Two robots are given three tries to push the other robot out of the ring.
If a robot damages the contest ring beyond a "quick repair," it will be disqualified along with all other Sumo robots by the same builder.
Please be sure your robot will NOT harm the ring!
Chapter 1: Definition of a Match
Article 1 - Definition
A match involves two contestants (one operator per robot can be registered, but a mechanic may assist the operator) who operate robots that they have made themselves (either autonomous or remote control) in the sumo ring (Dohyo) according to the game rules (rules). The contest continues until a (Yuko) point is scored by one of the contestants. The referee will make the decision on when a point is scored.
Chapter 2: Dohyo Specifications
Article 2 - Definition of the Dohyo Interior
The dohyo interior is defined as the dohyo area surrounded by and including the border line.
Article 3 - Dohyo
A dohyo is a cylinder with a height of 5 cm (2 in.) and a diameter of 154 cm (60-5/8 in.), consisting of aluminum base and black, steel sheet metal on top.
- The top surface is a 154 cm (60-5/8 in.) diameter, cold-rolled steel sheet (ASTM A366) with a thickness of 3.2 mm (1/8 in.). The surface will be flat and smooth using a non-glossy black Melamine coating that was baked on at 130 degrees Celsius for 30 minutes.
- The starting lines (Shikiri-sen) are indicated as two parallel brown (color ratio-blue : red : yellow = 4 : 4 : 2) lines with a width of 2 cm (25/32 in.) and a length of 20 cm (7-7/8 in.). The outside edge of each line is 20 cm (7-7/8 in.) apart, and they are centered on the dohyo.
- The outer edge of the dohyo, the border line, is indicated as a white circular ring with a width of 5 cm (2 in.) and an outside diameter of 154 cm (60-5/8 in.). "On the border" is defined as being within the interior of the dohyo.
- During the games, it is up to the referee to decide whether the dohyo can continue to be used or whether it should be replaced.
Article 4 - Dohyo Exterior
The exterior area of a dohyo extends at least 100 cm (39-3/8 in.) from the border line. The color of the exterior can be any color except white. There are no restrictions on the type of material that can be used or the shape of the exterior, as long as they do not violate the spirit of the rules.
Chapter 3: Robot Specifications
Article 5 - Specifications
- The robot must be able to fit in a box with a width and depth of 20 cm (7-7/8 in.). There are no restrictions on height.
- Weight (including accessories) must not exceed 3 kg (6.61 lb.).
- There are no restrictions on the type of control method used with autonomous robots.
- An autonomous robot should be designed to begin action no earlier than five seconds after the contestant presses the robot's start button.
- There are no restrictions on the type of microprocessor or the amount of memory used in the robot.
Article 6 - Restrictions on Robot Design
- The robot will not include a device that obstructs the control of the opponent's operation, such as a jamming device or strobe light.
- The robot will not include any parts that might damage or deface the dohyo.
- The robot will not include a device that insufflates any liquid, powder, or gas.
- The robot will not include an inflaming device.
- The robot will not include a throwing device.
- The robot will not include any part that fixes the robot to the dohyo surface and prevents it from moving (such as suckers, glue, and so on).
Chapter 4: Game Principles
Article 7 - Game Principles
- A game consists of three matches of three minutes each. The first contestant to win two Yuko points is the winner of the game.
- The contestant who has the most Yuko points at the end of the game will be judged as the winner.
- When neither contestant receives any Yuko points, or both contestants have one Yoko point, the winner will be decided by the judges. However, if no obvious superiority exists and a winner cannot be determined, an extra three-minute match can be played.
Chapter 5: Game Procedure
Article 8 - Beginning of the Game
Before the match, the contestants bow to each other outside the dohyo following the chief referee's instructions, then enter the dohyo. After that, the contestants put their robots on or behind their starting lines. No part of the robot can be placed in front of the starting line before the match begins.
- With an autonomous robot, the contestant can press the start button on the robot at the referee's signal. The match begins five seconds after the referee's signal. The contestant exits the dohyo when the match begins.
Article 9 - End of the Game
The match ends when the referee calls the winner. Both contestants bow after removing their robots.
Article 10 - Game Cancellation and Rematches
A match will be stopped and a rematch will be started under the following conditions:
- The robots are locked together in such a way that no more action appears to be possible or they rotate in circles several times.
- Both robots touch the exterior of the dohyo at the same time.
- Any other conditions under which the referee judges that no winner can be decided.
- In case of a rematch, maintenance of competing robots is prohibited until a Yuko is observed, and the robots must be immediately put back to the location specified in Article 8.
- If neither of the competing robots win nor lose after a rematch, the referee may reposition both robots to a specified location and restart. If even that does not yield a winner, the match may continue at any location decided by the referee, until the time limit is reached.
Chapter 6: Yuko (Effective) Points
Article 11 - Yuko
The following conditions are determined as Yuko (effective) points:
- When a robot ejects its opponent from the dohyo with a fair action.
- When the opponent's robot steps out of dohyo on its own (for any reason).
- When the opponent's robot is disqualified or has had more than one violation or warning.
- When two Yusei points are given.
Article 12 - Yusei
The following condition is determined as Yusei (advantage) points:
A Yuko point will be given when two Yusei points are given. A Yuko point will also be given when a Yusei point is given and the opponent has already been given a warning.
- When the opponent's robot gets stuck on the border line and cannot move off the border line on its own.
Chapter 7: Violations and Penalties
Article 13 - Warnings
A contestant who takes any of the following actions will receive a warning:
When a contestant receives two warnings, the contestant's opponent will be awarded one Yuko point.
- The operator or any part of the operator enters the dohyo before the referee's call ends the match.
- Preparation for the restart of a match takes more than 30 seconds.
- An autonomous robot begins action (physical expansion or moving) within five seconds after the chief referee's start signal.
- Any other actions that may be deemed unfair occur.
Any of the following actions is determined as a violation, and the offender's opponent, or both robots, will get a Yuko point:
- A part (or parts) of the robot that exceeds a weight of 10 grams is separated and dropped from the robot.
- The robot stops moving on the dohyo.
- Both the robots are moving, but don't contact each other.
- The robot emits smoke.
Article 15 - Loss by Violation
A contestant who takes any of the following actions will lose the game by violation:
- A contestant does not attend the appointed dohyo when called at the beginning of the game.
- A contestant ruins the game, such as by intentionally breaking, damaging, or defacing the dohyo.
Article 16 - Disqualification
A contestant who takes any of the following actions will be disqualified and forced to leave the game:
A disqualified person will lose the right to enter any national tournaments.
- A contestant's robot does not meet the robot specifications stated in Article 5.
- A contestant makes a robot using a method restricted in Article 6.
- A contestant displays unsportsmanlike behavior. For example, using violent language or slandering an opponent or a referee.
- A contestant intentionally injures the opponent's operator.
Chapter 8: Injury and Accidents
Article 17 - Request for Suspension
When a contestant is injured due to the operation of the robot or the robot has an accident, and the game cannot be continued, a suspension can be requested by the contestant.
A referee must take immediate action necessary to take care of this situation.
Chapter 9: Objections
Article 18 - Objections to the Referee
No objections to the judgment of the referee can be raised.
Article 19 - Objections to the Rules
A contestant who has an objection to the operating rules must express dissent to the Tournament Committee before the end of the game.
Chapter 10: Specifications of Robot Markings
Article 20 - Marks on the Robot
The east side contestant must put two red marks of at least 2 cm (25/32 in.) in diameter on the robot. The west side contestant must put blue marks of the same size and in the same places.
Chapter 11: Others
Article 21 - Modifications and Abolition of the Rules
Modifications or abolition of the rules are made by the decision of a general assembly of the Tournament Committees held according to the Rules of Tournament Committees.
The rules presented here follow the official Japanese Robot Sumo rules as
of 7/4/2002. Main differences is the changing of the radio frequencies to frequencies that meet FCC regulations, adding english units to the metric dimensions, and using a U.S. steel specification for the dohyo surface.
The rules for all of the weight divisions are the same. The only difference between them are the sizes of the robots and sumo ring.