Kids, Code, and Computer Science Magazine


Sumobots smash into each other and can be a fun project to create. Free plans are online. Upload your plan to services which send you the parts.

Try googling ‘sumobot’ and you will likely find a range of robots capable of pushing other sumobots around in a robot sumo competition.

These fun, entry-level, bots are created for robotics competitions and usually sold for between $99 and $160. For those interested in taking a more do-it-yourself approach to robotics and hoping the keep costs down, Sumobot Jr. is a fun beginner project.


Here are a couple of sumobots built and decorated

The term ‘beginner project’ likely means different things to different people. In the case of building a Sumobot Jr., ideally at least one person working on the robot will be familiar with servos and have a basic understanding of Arduino or similar microcontrollers. If not, a willingness to play around with both for a couple hours before building the robot should suffice. These robots can be wired without any soldering, and even the body can be held together with household glue.

That said, there a few steps, some of which may sound intimidating, required to purchase the parts of this bot.

This Sumobot Jr. does not come in a kit available to purchase at a maker store or even on Amazon. Instead, Nodebots created the robot body and uploaded the design to GitHub. This design document can be downloaded as-is and sent to a laser-cutting service or 3D printed. For the uninitiated this might sound overwhelming. However it basically boils down to downloading the design from one site and uploading it to another.

Makers can customize their bot by choosing various types of wood (or other material) to have it cut from, playing around with the design posted on GitHub, or simply decorating it after the robot is built.

In addition to having the robot body laser cut and shipped, there are a few more required parts:

  • two continuous rotating servos are needed to make the robot wheels turn
  • a microcontroller (such as Arduino) is needed to control the bot
  • a small breadboard and jumper wires are used to wire it all up, a 9V battery and cap (or AA battery pack with a solderless connector) brings the bot to life

A microcomputer and breadboard connected to a sumobot

Depending on the exact materials purchased, the price tag for a complete Sumobot Jr. need not exceed $70, and could range from around $60-$80, including the microcontroller. The only tools Sumobot Jr. builders need to have on hand are sandpaper (the laser-cut parts might need a bit of sanding down in order to fit together), and a small screwdriver for the servos. Zip ties will come in handy as well.

The less technical of us can control the Sumobot Jr. using the arrows on our computer keyboard, while those who like to dabble in JavaScript can program their homemade robots. To really spruce up the sumobot, it might be fun to try out a wireless microcontroller and use bluetooth to drive your new robot.

With adult support, most children from ages 8 on up will be able to do the bulk of the making, and kids as young as 6 should be able to contribute quite a bit as well. Upper elementary students (and older) that have some background in robotics could likely complete a Sumobot Jr. independently.

As such, the Sumobot Jr. makes a fun family project, robotics camp activity, or even class project for middle school on up if funding is available.

Ready to get started? Take a look at the links below, all collected from on the makenai/sumobot-jr Github site.

Learn More

Solder-Free Sumobot

Sumobot Instructional Video

The video does show soldering, however this can be avoided by ordering servos with solderless connectors referred to in the list of parts linked.

Sumobot Jr. Design File

Solderless 4-cell Battery Holder

Sumobot Additional Parts

Sumobot Wiring Diagram and Setup

A 3D Printing Option

Ponko Laser Cutting Service

Expect the laser cutting and shipping to come to between $10.00-$20.00 depending on the material you choose.

Also In The December 2015 Issue

The history of an egg shaped outdoor sculpture made of electronic parts in Palo Alto, California.

Use a software app to invent neat things by mixing SAM wireless blocks. No wires and no code needed.

How to Build a Computer

Building your own computer is a great way to not only save money, and get more processing power, but also to learn about the less obvious parts of software programming.

We might think robots are a modern invention. But al-Jazari created amazing automatons in the thirteenth century. Today we would call him a maker.

The Google Cardboard project is a fun way to experience virtual reality with your phone and software apps.

Sumobots smash into each other and can be a fun project to create. Free plans are online. Upload your plan to services which send you the parts.

How our all girls high school robotics team designed then built a robot to compete in FIRST competitions next year.

This key part of electronics projects turns out to be easy to understand. Learn about breadboards by building a simple LED project with a 9V battery.

Learn more than a language. Learn skills you need to use the language. Options to suit the way you learn best.

Use dice from a board game or toy store to create difficult to crack passwords and phrases that you can remember.

Learning how to make, track, and complete goals also helps with school projects and personal projects.

An essay from the 1990s explores how software can be built like a cathedral or in groups like a bazaar.

The Clojure programming language provides the simplicity of a Lisp programming language with the ability to run in the Java Virtual Machine (JVM).

Beyond Microsoft Windows and Mac OSX there are many Linux operating systems used by programmers daily and built as open source.

Interesting stories about computer science, software programming, and technology found online since the last issue of the magazine.

Links from the bottom of all the December 2015 articles, collected in one place for you to print, share, or bookmark.