From pololu.com: “The Pololu Zumo robot is an Arduino-controllable tracked robot platform that is less than 10 cm × 10 cm—small enough to qualify for Mini Sumo. It includes two micro metal gearmotors coupled to a pair of silicone tracks, a stainless steel bulldozer-style blade, an array of six infrared reflectance sensors for line following or edge detection, a buzzer for simple sounds and music, a 3-axis accelerometer, magnetometer, and gyro for detecting impacts and tracking orientation.”
I ordered my little Zumo kit and the reflectance detector array as part of a Black-Friday online buying spree (I went a little nuts) and got it along with an m3pi and a couple other robots or platforms. The kit I ordered was not assembled and it required some soldering. The soldering needed was basic enough, though soldering the battery terminals into place made the kit much more difficult to take apart should I decide to add more parts later. But, once together you have a very capable, fun little robot shield for your Arduino Uno compatible microcontroller. I paired mine with an Uno clone by OSEPP which you can find at Fry’s Electronics. It has a black board which matches nicely to the black robot.
The kit also required the addition of the motors. Since this is one of the customizable parts of the robot they don’t include them with the unassembled kit. I went with the 75:1 geared motors. They are pretty fast and will provide some torque when it’s sumo time. Though, in all honesty, when the time comes I may swap these out for a higher gear ratio to get even more torque out of them.
Using the Arduino makes it very easy to program and customize. In time I will be adding a couple range finders for simple object detection so I can set the Zumo up for sumo competitions. At the time of this writing, however, I have a simple line following program loaded into it. It zips happily around the track, following the black line.
If you’re new to robotics and are more interested in the programming aspect than the build aspect, then this may be a great entry point for you. Again, the kit itself is fairly complete and easy to build. It uses the common differential drive system (tank drive) which makes control simple. The Arduino makes it simple to program and once you’ve grown past this and into more advanced programming, you can easily configure the Zumo to be a dedicated sumo-bot and still have loads of fun.
You can order one directly from Pololu here: https://www.pololu.com/product/2509
The motors I used are these: https://www.pololu.com/product/2361