Mini Sumo Bot Class and Competition

The Idea

Have a class for all ages that includes a very low cost ($20-50) kit with laser cut and/or 3D printed parts to build mini sumo robots. Then have a tournament to battle them!

NOTE: Here is an example obstacle-avoidance robot with only one sensor has an approx. cost of $25.
$20 would be great, but unless we can find replacements for some of the Pololu components - I don’t see the sumo robot being realistic for under $30.

The Class

Everything you need to know to build a mini sumo bot:
1. Tournament Rules
2. Existing robot styles
3. Kit parts / different styles of kit bodies, motors, wheels, treads, sensors, etc.
4. Programming - how to read the sensors then move the robot
Learn even more at James’ website:

The Tournament

Follows existing international tournament rules:

Here are some examples of tournament fights:

Here’s what the bigger weight class can do:

Here is a good video showing some types of strategies:

The Kit

Here’s all the ideas for parts to create low cost kits:

Total Kit Cost = $26.07

| QTY | Vendor | Description | Cost Each | Ext Cost | Link |

  • 1 E-Bay Arduino Uno R3 (Clone) with cable $4.45 $4.45 Link
  • 1 E-Bay Motor Drive Shield for Uno $2.39 $2.39 Link
  • 1 E-Bay 4-x-AA-6V-Battery-Holder-ConnectorStorage-Case-Box-ON-OFF-Switch-WithLead-Wire $1.39 $1.39 Link
  • 2 E-Bay DC 3-6V 100RPM Mini Electric Reduction Plastic DC Gear Motor For Toy car K248 $2.40 $4.80 Link
  • 1 E-Bay 5Pcs-5V-Infrared-Line-Track-TrackerTracking-Follower-Sensor-Shield-ForArduino ($2.47 for 5) $0.50 $0.50 Link
  • 1 E-Bay Sharp Range Sensor $4.35 $4.35 Link
  • 4 MMC 4-40 RH machine screw 1.25 inches long 90272A117 ($9.10/100) $0.09 $0.36
  • 4 MMC 4-40 hex nut 90480A005 ($0.87/100) $0.01 $0.04
  • 8 MMC Nylon Pan Head Machine Screw, Phillips, 4-40 Thread, 5/16" Length, packs of 100 93135A274 (5.17/100) $0.06 $0.48
  • 2 MMC 91780A171 Aluminum Female Threaded Hex Standoff, 1/4" Hex Size, 1-1/2" Length, 4-40 Thread Size $0.71 $1.42
  • 1 Coaxial power plug
  • 4 Groupon AA Alkaline Battery 1.5V $0.30 $1.20
  • MS 3D Printed wheels from OpenSCAD $0.80 $1.60
  • MS Laser-Cut Birch plywood body $2.00 $2.00
  • AN Harbor Freight Foam tape, 1” wide

Total Kit Cost $24.98

Robot Behavior Code

Here’s some arduino sketches that we will be using for the class as examples to make the robot do different things.

  • Behavior 1: Turn around at the area edge, go full speed ahead if opponent is detected in range. Note that you might need to install the FTDI drivers from here: Sparkfun FTDI Drivers


Here’s some pictures of the kit robot as well as the days we met up to figure out which parts to use to make a solid robot for as close to $30 as possible:
Melbourne Makerspace Kit Robot
Mini Sumo Bot Kit Brainstorming