Romi Chassis Kit - White

The versatile Romi chassis is a great starting point for your next mobile robot. This kit includes all the basic mechanical parts to get up and running, including two motors, two wheels, one ball castor, and battery contacts.

AUD$ 40.95

Special Order  

We can ship 41 more in 7-10 days

Our Code: SKU-003784

Supplier Link: [Pololu MPN:3509]



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 (not included). The drive wheels are located on a diameter of the circular base plate, allowing for turns or spinning in place. A large, fixed ball castor in the rear provides a smooth third point of contact, and a second ball castor (not included) 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.

The plastic components making up the chassis are available in six colors, either individually (for use as replacement parts or to make custom colour combinations) or in kits that include motors and battery contacts.

This animation shows how the parts fit together:

See the user’s guide for more complete assembly instructions.

Details for item #3509

Contents of the Romi Chassis Kit – White.

Romi Chassis Kit – White.

Kit contents

Additional required components (not included with the kit)

In addition to what comes with the kit, you will need the following:

You will likely also need a soldering iron for connecting your motors and batteries to your electronics.

Optional accessories

  • Power Distribution Board for Romi Chassis – This board helps you get your Romi chassis running quickly. It solders to the chassis’s battery contacts and provides reverse battery protection, several power switching options, and convenient access to the various power busses.

Power Distribution Board for Romi Chassis on a black chassis.

Power Distribution Board for Romi Chassis.

  • Motor Driver and Power Distribution Board for Romi Chassis – This board is an alternative to the Power Distribution Board mentioned above. It offers the same features (reverse battery protection, multiple power switching options, and convenient access to various power busses) along with dual motor drivers and a powerful switching step-down voltage regulator that can deliver 2.5 A at 5 V or 3.3 V.

Motor Driver and Power Distribution Board for Romi Chassis.

Motor Driver and Power Distribution Board for Romi Chassis.

  • Romi Encoder Pair Kit – Add quadrature encoders to the mini plastic gearmotors on your Romi chassis with this kit that uses a magnetic disc and Hall effect sensors to provide 12 counts per revolution of the motor shaft.

The included low-profile headers are still long enough to work with our pre-crimped jumper wires.

The Romi Encoder can plug directly into the Motor Driver and Power Distribution Board for Romi Chassis.

  • Romi Chassis components – Chassis components are available individually for use as spare parts or for those who want to put together their own Romi chassis with the colour combinations of their choosing.

Romi Chassis Base Plate – White.

Romi Chassis Motor Clip Pair – Blue.

Romi Chassis Ball Castor Kit – Red.

Pololu wheel 70×8mm pair – yellow.

  • Sensors.
  • Hardware (such as stand-offs, spacers, and fasteners).



Size: 163 × 149 × 70 mm
Weight: 160 g1

General specifications

Colour: white


Without batteries.


Documentation and other information

Pololu Romi Chassis User’s Guide

User’s manual for the Pololu Romi Chassis.

File downloads

Actual-size view of the top of the Romi Chassis (115k pdf)
Print this page at 100% scale to get an actual-size view of the top of the Romi Chassis and all of its general-purpose mounting holes and slots.
Front, top, and side view of the Romi chassis (9MB dxf)
This dxf makes it possible to get various dimension measurements of the Romi chassis and its mounting holes.

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