Overview

The 3pi+ 2040 is a versatile, high-performance, user-programmable robot that measures just 9.7 cm (3.8″) in diameter. At its heart is a Raspberry Pi RP2040 microcontroller (like the one on the Raspberry Pi Pico), a 32-bit dual-core Arm Cortex-M0+ processor running at 125 MHz, which can be programmed with C, C++, Arduino, or Python. The 3pi+ 2040 has 16 MB (128 Mbit) of flash memory that ships preloaded with a MicroPython interpreter, so you can get started right away by plugging into its USB C port and editing the included example Python programs. For advanced users who want to customize or enhance their robots with additional peripherals, the robot’s power rails, power system controls, and microcontroller’s I/O lines can be accessed via several 0.1″-pitch expansion ports.

3pi+ 2040 Robot, front view.

3pi+ 2040 Robot, side view.

3pi+ 2040 Robot, rear view.

The 3pi+ (or 3𝜋+) 2040 features two H-bridge motor drivers and a variety of integrated sensors, including a pair of quadrature encoders for closed-loop motor control, a complete inertial measurement unit (3-axis accelerometer, gyro, and magnetometer), five downward-facing reflectance sensors for line-following or edge-detection, and left and right bump sensors along the front face of the robot. Three on-board pushbuttons offer a convenient interface for user input, and a 128×64 graphical OLED display, buzzer, and six RGB LEDs allow the robot to provide feedback.

The robot also features a unique power system that runs the motors at a constant 8 V independent of the battery charge level, so the speed of the motors does not vary with the battery voltage.

The 3pi+ 2040 robot is available as a kit or fully assembled:

3pi+ 2040 Version	Products	Micro Metal Gearmotor	Top Speed	Comments
Standard Edition	assembled or kit	30:1 MP 6V	1.5 m/s	good combination of speed and controllability
Turtle Edition	assembled or kit	75:1 LP 6V	0.4 m/s	longest battery life, easiest to control, good for swarm robots or introductory robotics courses
Hyper Edition	assembled or kit	15:1 HPCB 6V	~4 m/s	very fast and difficult to control, easy to damage; only recommended for advanced users

For those who would prefer to use different motors than these versions above, the 3pi+ chassis and 3pi+ 2040 control board are available separately and can be combined with a pair of motors to make a custom kit.

What else you will need

• four AAA batteries: the 3pi+ robot works with both alkaline and NiMH batteries, though we recommend rechargeable NiMH cells
• a USB C cable to connect the robot to your computer for programming and debugging

Assembling the kit version

The following video shows the steps to assemble a different version of the 3pi+ robot (the 3pi+ 32U4 OLED robot), but these steps generally remain the same for the 3pi+ 2040:

Details for item #5005

This product is the kit version of the Turtle Edition 3pi+ 2040 Robot, which has a top speed of approximately 0.4 m/s and is well suited for applications where slow, controlled speed is important, such as coordinated swarm robots and introductory robotics courses. Assembly (including soldering) is required.

3pi+ 2040 Robot Kit (Standard or Turtle Edition).

This kit includes:

• 3pi+ Chassis Kit
• 3pi+ 2040 Control Board
• two 75:1 LP 6V Micro Metal Gearmotors with extended motor shafts
• one graphical OLED display

A pre-assembled version of this kit is also available.