FSI-All Japan Robot-Sumo Tournament
Robot Sumo Overview
Robot Sumo Overview Tournament Rules and Regulations Tournament Administration Course of Competition

How the matches proceed NEW 2004/06/11
1. What is Robot Sumo 6. Things to be considered during robot manufacturing
2. Robot Types 7. Maintenance Location
3. Ring Specification 8. Tournament Procedure
4. Robot Specifications 9. Winning and Losing
5. Prohibitions for robot construction  
1. What is Robot Sumo
In Robot Sumo, participants compete against each other using homebuilt robots within a ring (Dohyo). The tournament conforms to with the official rules, and the winner is determined by the judge's decision.
Match stage 1
Place the two robots onto the ring
Match stage 2
Match begins with the judge's announcement "Hakkeyoi nokotta (Ready, go!)"
Match stage 3
The first robot to be pushed off the ring loses.
Click the images below to view sample movies.
movie1 movie2 movie3
MPEG 576kb MPEG 160kb MPEG 449kb
2. Robot Types
There are 2 types of robots in Robot Sumo: Autonomous and Radio Controlled (R/C).The rules for determination of the winning robot are the same, but the methods of controlling the robots differ. Please familiarize yourself with the relatively simple robot construction regulations listed below in sections 4. and 5...
  1. Autonomous
    A Sumo Robot which contains microcontroller, sensors, and other devices which enable a robot to control itself.

  2. Radio Controlled
    A Sumo Robot which uses proportional control system, that lets people remotely control the robot.
3. Ring Specification
  1. The 3 kg class robot you built will compete on a specially constructed 154 cm diameter ring, while 10 kg class robot will compete on a 227 cm diameter ring. Both rings are made of cold-rolled steel sheet.
  2. The Robot Sumo is a combat sports where the robots stage a fierce battle against each other.
  3. The components may detach and fly off of the robots.
  4. To avoid danger, there is a "safety zone" set up 1m around perimeter of the ring.
  5. The ring and the safety zone are together defined as the "arena", and only the judges are allowed inside during the competition.
  6. The competitors are only allowed to enter the arena to place their robots on the starting lines and then remove the robots after the match.
  7. In an R/C match, the proportional control system is to be operated from the outside of the arena.
  8. The match begins with the judge's announcement, "Hakkeyoi nokotta (Ready, go!)".
  3 kg class Ring Diagram 10 kg class Ring Diagram
(Divided into 4 pieces)
Diameter 1m 54cm 2m 27cm
Construction Material Cold-rolled steel sheet Same as left
Inside the ring ---Black
Starting lines---Brown(Width 2cm Length 20cm)
Division lines inside and outside the ring ---White(5cm width)
Inside the ring---Same as left
Starting lines---Brown(Width 2cm, Length 30cm)
Boundary lines separating inside and outside of the ring ---White(10cm width)
Ring Surface
Less than 1000 lux Same as left
4. Robot Specifications
3kg Class 10kg Class
Width 20cm
Depth 20cm
Height Unlimited, as long as the robot fits inside a hollow 20cm x 20cm square frame.
Width 30cm
Depth 30cm
Height Unlimited, as long as the robot fits inside a hollow 30cm x 30cm square frame.
Each robot must weigh no more than 3 kg including all attachments. However, the weight of the proportional control system is excluded for the radio control robots.
Each robot must weigh no more than 10kg including all attachments. However, the weight of the proportional control system is excluded for the radio control robots.
Robots must be setup to start moving 5 seconds after pressing the ON-switch.
* Note: the R/C robots will start moving with the judge's announcement.
Same as left
Each robot must equip a fail-safe remote-controlled "shutdown device".
* Note: the R/C robot will be operated via proportional control system.
Same as left
5. Prohibitions for robot construction
  1. No built-in devices that disrupt opponents such as radio interference generator, strobe light, etc. are allowed.
  2. No components that damage and/or soil the ring surface are allowed.
  3. No built-in devices that contain and spray liquid, powder and/or gaseous matter toward the opponent are allowed.
  4. No built-in ignition devices are allowed.
  5. No built-in devices that throw and/or let fly objects are allowed.
  6. No components that affix a robot onto the ring and make it inoperative are allowed.
6. Things to be considered during robot manufacturing
  1. Any materials and components can be used as long as the above 4. and 5. terms are fulfilled.
  2. Any forms and shapes are accepted. Using empty cans, pots, etc., build a unique sumo robot showcasing the creative mechanisms to defeat the opponent and defend yourself.
  3. Therefore, just because you spent much money on the materials and components that does not mean that you will win.
  4. Your creative ideas mean the difference between victory and defeat that is what makes the Robot Sumo interesting.
7. Maintenance Location
You are allowed to work on your robot only in the maintenance area designated for each ring.
8. Tournament Procedure
  1. Each match is normally limited to 3 minutes, however, the length of a match may vary depending on how the match proceeds.
  2. You may disqualify if you are not standing by when your name is called to start the match.
  3. Please always pay attention to the progress of the tournaments and be ready for your turn.
9. Winning and Losing
It is very simple. "Whichever robot pushes the opponent out of the ring wins."?
a. Not lost yet b. Falling over doesn't mean that you have lost c. Even flipping over is not a loss either

  1. Even if you tip over the opponent, doesn't mean you have won the match.
  2. As shown above, unless a robot touches the safety zone outside the ring, falling over, tipping over or hanging off the ring won't mean you have lost the match.
  3. The robot is allowed to get up by itself.
d. You have lost in this position
  1. The first robot that touches the safety zone outside and below the ring will lose the match.
  2. The match lasts 3 minutes, this includes up to 3 rounds. The first one to take two rounds will win. If there is still a tie past the time limit, there will be an extended tie breaker rounds. First robot to score during the tie breaker rounds wins the match.
Due to the uniqueness of this competition and its rules the audience enjoys many different aspects of robot sumo: creative robot engineering ideas, combat methods, robots that rise from near defeat in a flipped upside-down position or at the edges of the ring and come back to challenge their opponent. That is what the audience loves to cheer and applaud.
The regulations for building a robot as well as the combat rules are very simple.
However, once you actually build a robot and/or participate in a tournament, you will realize there is more depth to the Robot Sumo.
While building a robot, you will utilize current skills and acquire a few new tricks. You will find and use new and unexpected materials, as well as apply new usage to the old parts. You will experience various ups and downs during the matches. It will be filled with laughter and tears.
Well then. Let's build your Sumo Robot.
Enter the Robot Sumo Tournament and walk away with the glorious victory!
Robot Sumo Overview
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