One version of the LoCoRo project uses two drive wheels and a single small free castering front wheel. This model uses differential drive similar to that used on a zero-radius lawnmower.
The choice of wheels is open to builder. There are commercially available wheels and wheels can even be made from the plastic jar tops like those found on peanut butter. Builders may choose to design and 3D print their own custom wheels.
The low cost robot project provides a starter design for users to print or customize their own wheels. It is a 120mm diameter wheel with a recess in the center for the RC servo’s attachment horn. The wheel may optionally use a rubber band as the “tread” for traction on smooth floors.