Mini-Sumo Robot Contest – PPE’13

This page will be for a Robotic Sumo Wrestling contest at the Official PropellerPowered Expo – 2013.

Well, it was a long weekend; but it was great.

Here are the results of the robot contests:

Sumo –
– In first place, with 2 wins and 1 loss, was Thing1, owned by Chris and Abby Wardell
– In second place, with 1 win and 2 losses, was Thing2, owned by Chris and Abby Wardell

Congrats to all of our entrants, and thank you for a most entertaining contest.

For the trivia collector: Chris and Abby’s robots were named after Thing1 and Thing2 from the Cat in the Hat (  Thank you Abby for those imaginative names.

This Sumo contest is similar to a human Sumo contest.  Wikipedia gives a nice introduction to this sport.

From Wikipedia, the free encyclopedia:

“Sumo (相撲 sumō?) is a competitive full-contact wrestling sport where a rikishi (wrestler) attempts to force another wrestler out of a circular ring (dohyō) or to touch the ground with anything other than the soles of the feet.

Sumo (相撲)
Asashoryu fight Jan08.JPG
A sumo match (tori-kumi) between yokozuna Asashōryū (left) and then-komusubi Kotoshōgiku in January 2008.


Well, the robotic sumo competition is like that: two robots will face each other in a circular ring (dohyō – from my memory of my martial arts classes when I was a kid, it is pronounced as DO-JO, but I could be wrong,) and the first robot to touch outside the ring looses.  [MindRobots] has graciously offered us the use of his dohyō, and so we will use that for the contests.  If you want an idea of what the dohyō will be like, take a look at what Parallax’s Competition Ring looks like (

The dohyō is a 3′ x 3′ 3/4″ plywood square.  There is a 26″ diameter flat black circle in the middle of the square. The black circle is surrounded by a 1″ flat white band. The area outside the white band is painted gray.    The first robot to have any part of itself outside the white boundary line will loose that round.

Here is a photo of the dohyō:

We will be using a double-elimination type tournament.  This means that each robot will wrestle, at least, twice.  A robot will not be eliminated unless it has lost two matches.  Scheduling will not be able to begin until we know the number of robots to be entered.

The class that we will be fighting will be the Mini-Sumo class.  This means that the robots may not mass more than 500 grams (1.1 pounds,) and must be no more than 10 cm wide and 10 cm long.  There is no restriction on the height of the robot.  Any ‘bot built on the Parallax Sumobot platform ( should fit the size restrictions, but don’t forget that it cannot get over 500 grams.  Also, since this is a Propeller Expo, the ‘bot should be controlled by a Propeller chip.

Also, since this is a sport, we do not want anything that can damage or destroy the other robot, the dohyō or the building.  That means no flame, no liquids, no blades, no missiles or anything else that would turn this event into a non-sport.

Well, thanks to the wonderful people at, we have schedules printed out for the Sumo Contest.  I printed out several because we do not know how many ‘bots will be entered.  This way, I can just grab the schedule for the number of entries, and away we go.

2013-06-26 – Edited to correct the length and width specifications (from 5cm to 10cm per side,) and to update the title. Thanks [ctwardell], from the PropellerPowered forums.

2013-08-13 – Edited to post about the schedules.  Thanks people.

2013-08-20 – Edited to post the results of the contests.

Leave a Reply

Your email address will not be published. Required fields are marked *