The Romi chassis is a differential-drive mobile robot platform with a diameter of 6.5″ (165 mm) and an integrated battery holder for six AA batteries. The drive wheels are located on a diameter of the circular base plate, allowing for turns or spinning in place. A large, fixed ball caster in the rear provides a smooth third point of contact, and a second ball caster can optionally be added to the front. The chassis uses 70×8mm Pololu wheels and Mini Plastic Gearmotors with extended backshafts to enable quadrature encoders for position feedback.
The Romi chassis has an abundance of general-purpose mounting holes and slots intended for various sizes of screws (not included) such as #2-56, #4-40, M2, and M3. These holes can be used for mounting your electronics, such as your microcontroller, motor drivers, and sensors.