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Robot Sumo Wrestling


Class A Sumo: Pairs of robots attempt to push each other off the edge of a 5ft round platform (the "Douyou"). Contestants can be either self-contained, tethered, or radio controlled. Last one still in the ring wins.

Class B Sumo: Robots must attempt to push each other off the edge of a 6ft round platform, but they can be more aggressive about it. If a tie is declared, the winner will be based upon perceived aggressiveness.

Contents of this page:

Competitor Design Parameters

For both A and B classes, the following restrictions apply:

1.The initial dimensions of all robotic competitors must fit within the boundaries of a 1 foot cube. (there is a unlimited height/length exception for antennas and tethers). Once the trial has begun, however, the machine may expand its dimensions as required, so long as it does not extend past the edge of the competition ring.

2.All robots must have a self-contained electrical power source right in the sumo device. No power from control tethers or any outside sources will be allowed.

3.No robot can use any power source or weapons which involves a combustion process.

4.Robots cannot use any gravity-assisting devices (i.e.: suction cups, compressed air jets, etc.). As well, all devices must be horizontally mobile (no rotating cinder-blocks allowed). There is no weight restriction, providing that each competing machine is capable of moving itself across the surface of the playing field during the full duration of each trial.

5.Control tethers between machine and human operator can be used only to carry control signals. Any devices which run by tethers must not use their tethers as weapons, lassos, or for any type of mechanical assistance in the competition. However, any robots who get caught up in their own tethers are fair game for the opposing device to take advantage of. Tethers cannot furnish additional power to the machine or deliberately entangle the opponent. For the safety of the operators, no cords carrying voltages in excess of 25 volts DC (17.6 volts AC) will be allowed.

6.Robot operators are allowed to rove around the sumo ring as necessary to insure their tethers remain clear, so long as they do not interfere with their opponents vision or operation.

7.The judges may bar from the contest any machines which they feel pose a real threat of damage to spectators or the contest ring. As well, any judge may stop a trial at any time, if it appears to that judge that a danger to spectators or site is imminent.

Class A Sumo

(The class A robosumo rules are modifications of the official competition rules as are practiced throughout Japan since December of 1989. Japanese rules seem to be essentially similar, except that their machines have a maximum 20 cm base dimension and a maximum 3 kg weight limit. Following an article in the New York Times about the 1989 Robot Sumo competition, we decided to include such a competition in our own games. Having only the article though, we've had to guess at the rules, and they have evolved considerably as various competitions have come and gone.

We give thanks, however, to whoever it was that first thought up what has become a rollicking staple of international robotic competitions).

For class A robosumo, the following restrictions apply:

1.No robot can deposit any fluids or "mines" of any sort on the ring surface, only non-intelligent chaff like ball-bearings. Such chaff must be directed against the floor and not at the opponent. Any machine exhibiting tactics which extend beyond the dimensions of the ring that could even remotely harm a human operator, judge, or audience member will be immediately disqualified.

2.No robot may launch any attack upon an opponents hardware (cutting wires, using spring-rams to destroy mechanisms, etc.) and all intentional contact between opponents must be within half an inch (1/2") of the floor.

3.No robot may exceed a weight of 10 Kilograms. There is no minimum weight requirement.

4.No robot can deliberately damage the ring surface.

5.Only one human operator is allowed per robotic device.

Class B Sumo

(The idea for Class B Robosumo belongs to Norman White of the Ontario College of Art in Toronto, Canada. The idea was to have a "no-holds barred" competition where competitors agreed to waive the "no damage" rule, and take whatever was coming to them. Initial results were so much fun that we just had to make it a legitimate class for the BEAM Robot Games. The following rules are in dead earnest, and it should be noted that BEAM Robotics and its affiliations can take no responsibility for injuries or damage incurred or inflicted by this contest to either man, machine, reputations, or floor work. We trust your designs to be whimsical, not dangerous.)

For B class robosumo, the following restrictions apply:

1.Prior to the first competition, each competing team must demonstrate in full all aggressive features used by their Sumobot (such information will be kept confidential by the judges on request).

2.NO aggressive aspect of a robot must extend beyond the competition boundary. The idea here is to protect the audience, judges, and other human operators from any possible harm. Violators will be immediately disqualified.

3.No robot may fire projectile weapons of any sort, unless the projectile(s) are chained to the host robot to the judges satisfaction. All projectiles should be either deposited, dropped, scattered, or flicked against the opponent.

4.No Sumobot can use any slippery, sticky, flammable, explosive, caustic, corrosive, or damaging chemicals in their attack. This includes oils, paints, juices, and any substance which gives off noxious odors. Allowable substances include (but are not limited to) saline solution, tap water, shaving foam, and jello. Contact the organizers for a ruling.

5.All exposed rotating elements on a Sumobot must not exceed 1000 RPM. No rotating element can exceed 1/4 pound (275 grams) in mass. Rotating elements must not be composed of sharp, brittle, or ragged substances which could fly off and damage the crowd.

6.No Sumobot can use a smoke-screen, or any tactic which deliberately hides the action of the robots from the operators, judges, or audiences view.

7.No Sumobot can use a "spot welding" tactic by pressing a high-power battery across the opponents conductive surfaces (batteries tend to explode this way).

8.No design team controlling a Sumobot can launch a physical attack on the opposing team. Language is the exception to this rule.

9.Any designer or competitor that catches fire will be disqualified. Slight smoking is permissible, so long as it is not a precursor to an explosion.

10.High traction wheels (i.e.: buzzsaw blades, chains) are permissible so long as they do not gouge the play surface to a depth of more than 1/8 inch. As well, no device may employ a method of deliberately fastening itself to the ring floor.

11.Devices which either jam the opponents radio frequencies, or cut the opponent's control cable, are permitted. Therefore, control cables carrying currents greater than 1/2 amp must be fuse-protected. Any frequency jammers must be contained within the Sumo device itself.

12.No more than two human operators are allowed per robotic competitor.

The Ring

Class A Sumo: The Class A Sumo Ring is 5 feet across and perfectly round. It is raised above the floor exactly 2" and is perfectly level. The internal floor of the ring is burnished black arborite with a 2" bone white border. The border is flush with the internal surface. Competitors start "facing" each other, 1 foot apart, 6" from the ring center. There is no surrounding wall of any type.

Class B Sumo: The Class "B" Sumo Ring is 6 feet across and also perfectly round, however, unlike the "A" class, it is just a surface of cheap plywood, painted black with a white border, and raised 2" above the floor. Competitors must accept that as competition progresses, this floor will not remain ideal, and that although the surface will be cleaned between bouts, imperfections will accumulate.

Competition Procedure:

These procedures will be followed for both A and B classes. Matches will consist of three trials. The best of two competitors out of the three trials will be awarded the match.

The object for a competing machine during the course of a trial will be to remain within the boundary of the circular field longer than one's opponent. A trial starts with both machines "facing off" in the center of the ring exactly one foot apart. Once a starting command is given, no one other than a judge may touch a competing machine until a win or tie is declared.

If both machines leave the field, it will be up to the judges to decide which one left first. If neither machine crosses the boundary within two minutes, that trial will be declared a tie. If the result of a given match is three ties, then the judges will chose a winner on the basis of aggressiveness and operator skill. In case of a dispute, the audience will decide.

A trial starts in two ways, but both start when a whistle is blown. For human-operated devices, play starts immediately. For autonomous devices, a first whistle means exactly 5 seconds before the competitors can move, and a second whistle happens exactly at the 0 mark. All human operators must be outside the ring by the blowing of the second whistle. Any device which moves towards its opponent before that time will force a restart of the trial. Three restarts will disqualify a competitor from that match. The match may be re-run later, but only if the problem is fixed to the judge's satisfaction.

A trial ends when an one entrant leaves the ring or 2 minutes have passed. If one entrant becomes damaged, play continues unless undue roughness is observed and/or the loosing robot's designer concedes the match. If both entrants are incapacitated (i.e.: flipped or excessively damaged) then the trial is restarted. If the cause of repeated incapacitation is some obvious design defect, then the designer(s) will be asked to remove and repair the device. Play continues in round-robin elimination except for the final three sorties which will be a best-of-five contest, to account for strong equivalencies between designs.

Competition continues until all winners and secondary winners have faced each other. Prizes will be awarded individually to best autonomous, best radio-controlled, and best tethered Sumobot designs.