Charlie, my Mindstorms chess robot, rebuilt ten years after the first version. A phone now does all the vision.

Around 3100 parts, mostly NXT era Technic, plus 3D printed pieces : the guards, the phone stand and part of the gripper itself. The first version dates from 2015 and needed a laptop running MATLAB next to it to see the board. This one uses the phone camera instead, so the whole thing is the robot, a board and a phone on a stand. The tricky part mechanically was the capture: it has to lift your piece off the board and park it before it can play its own move, without knocking over the...