3pi+ 32U4 Control Board

The 3pi+ 32U4 Control Board is designed to be assembled with a 3pi+ Chassis Kit and a pair of 6V Micro Metal Gearmotors with extended motor shafts to create a 3pi+ 32U4 robot. This product is primarily intended as a replacement product for the 3pi+ 32U4 robots and kits that already include it or for those who want to build a 3pi+ 32U4 robot with different gearmotor versions than the ones offered with those complete kits and assembled robots.

Included components
The 3pi+ 32U4 Control Board ships with all of its surface-mount components populated, and it includes the following through-hole parts and mounting hardware:

• one buzzer
• jumper wires for soldering motors to the board
• two magnetic encoder discs
• one low-profile 2×7 male header for use with an 8×2 character LCD (not included)
• four single battery contacts
• four 3/16″ #2-56 screws and nuts for mounting the board to a 3pi+ Chassis

Please note that assembly (including soldering) is required; see the user’s guide for assembly instructions.


The 3pi+ 32U4 offers many major improvements over the original 3pi, including:

• ATmega32U4 microcontroller with Arduino-compatible bootloader can be programmed directly through a USB connection
• Quadrature encoders on both motors for closed-loop position and speed control
• Full 9-axis IMU (three-axis gyro, accelerometer, and compass)
• Bottom-loading battery holders keep batteries accessible even if additional levels are added
• Full wrap-around bumper to protect electronics from collisions
• Two bump sensors on the front

The 3pi+ 32U4 uses a different microcontroller with different pin mappings compared to the older 3pi, and some of the software library interfaces are different, so programs written for the original 3pi will not work on the 3pi+ 32U4 without modification.