Open Source TurtleBot 3 Robot Kit Runs Ubuntu and ROS on Raspberry Pi Linux.com (blog) The Raspberry Pi or Intel Joule boards work together with a fully open source OpenCR control board built by Robotis that runs Arduino IDE code on a Cortex-M7 STM32F7 MCU.

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Open Source TurtleBot 3 Robot Kit Runs Ubuntu and ROS on Raspberry Pi – Linux.com (blog)