Chapter 1 Definition of a match
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 self-operated or remote control type) 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 decision on when a point is scored will be made by the referee.
Chapter 2 Dohyo Specifications
Definition of the Dohyo interior
The Dohyo interior is defined as the Dohyo area surrounded by and including the border line.
A Dohyo is an aluminum cylinder with a height of 5 cm and a diameter of 154cm (including the border line).
A hard black rubber (long-type vinyl sheet NC, No. R289 made by Toyo Linoleum, Inc.) sheet is attached to the top of the cylinder.
- The starting lines ("Sikiri-Sen") are indicated as two brown lines with a width of 2 cm and a length of 20 cm.
Each line is located 20 cm from the center of the Dohyo.
- The border line is indicated as a white circle with a width of 5 cm.
"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 changed when a scratch or tear less than 5 cm in length appears on the Dohyo surface.
The exterior area of a Dohyo extends at least 100 cm 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 Specifications of the robots
The robot must be able to fit in a box with a width and depth of 20 cm. There are no restrictions on height.
- Weight (including accessories) must not exceed 3 kg. However, the wireless remote control unit of a remote control robot is excluded.
- Usable frequencies for remote control robots are 27 MHz (Narrow bands between 1 - 12) and
40 MHz (Bands 61, 63, 65, 67, 69, 71, 73, 75)
- Usable remote control units are limited to the following brands:
Futaba, JR, Sanwa, Kondo Kagaku(KO Propo).
Multiple remote control units cannot be used. When you use 27 MHz,
use a remote control unit that's compatible with narrow bands.
- A remote control robot must use a crystal receiver prepared by the Tournament Office.
Consequently, the robot's receiver section must be detachable.
- There are no restrictions on the type of control method used with self-operated robots.
- A self-operated robot should be designed to begin action about 5 seconds after the contestant presses the robot's start button.
- There are no restrictions on the brand or memory volume of the microprocessor used for a robot.
Restrictions on robot design
The robot must not include a device that obstructs the opponent's operation, such as a
jammer or strobe light.
- The robot must not include any parts that might damage or deface the Dohyo.
- The robot must not include a device that insufflates liquid, powder or gas.
- The robot must not include a firing device.
- The robot must not include a throwing device.
- The robot must 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
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 wins a Yuko point at the end of the game is judged as the winner.
When neither contestant receives any Yuko points, the winner is decided by judgment. However, if no obvious superiority exists and a winner can still not be determined, an extra three-minute match can be played.
Chapter 5 Game procedure
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.
The robot cannot outstep the starting line before the match begins.
- With a remote control robot, the match begins when the contestant begins operating the robot with a remote control unit after the referee's signal.
- With a self-operated robot,
the contestant presses the start button on the robot at the referee's signal.
The match begins when the robot begins action (after about 5 seconds).
The contestant exits the Dohyo when the match begins.
End of the game
The match ends when the referee calls the winner. Both contestants bow after removing their robots.
Game canceling and rematches
A match will be canceled or rematched under the following conditions:
- The robots are locked together in such a way that no more action is 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 are prohibited until
a "YUKO" is observed, and the robots must immediately be put back to the
location specified in Chapter 8 Article 16.
- If neither of the competing robots win nor loose even 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 the location
decided by the referee, until the time limit is reached.
Chapter 6 Yuko (effective) points
The following conditions are determined as Yuko 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.
Chapter 7 Violations and penalties
A contestant who takes any of the following actions will receive a warning:
- The operator or a part of the operator (remote control etc.) enters the Dohyo before the referee's call ends the match.
- Preparation for the restart of a match takes more than 30 minutes.
- The robot begins action (physical expansion or moving) before the chief referee's start signal.
- Any other actions that may be deemed unfair.
Any of the following actions is determined as a violation, and the offender's opponent or both will get a Yuko:
- A part or parts of the robot that exceed a weight of 10 g are 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.
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 who ruins the game. For example, by intentionally breaking, damaging or defacing the Dohyo.
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 the National Convention and to receive a commendation:
- A contestant's robot does not meet the "Specifications of the robots" 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.
Chapter 8 Injury and accidents
Request for suspension
When a contestant is injured or the robot has an accident,
and the game can not be continued,
a suspension of maximum five minutes can be requested by the contestant.
Chapter 9 Objections
Objections to the referee
No objections to the judgment of the referee can be raised.
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
Mark on the robot
The east side contestant must put two red marks of at least 2 cm in length on the robot.
The west side contestant must put blue marks of the same size and in the same places.
Chapter 11 Others
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.
June 20th, 1997