Each and Every Chess Piece Is a Robot

We’ve seen robotics applied to chess many times and the projects always fall into one of two categories: a robot arm that picks up and moves pieces, or an under-table motion system that grabs pieces with magnets. So, I was really excited when I saw a completely new approach. 3DPrintedLife made each and every chess piece a tiny robot.

To set the right expectations, I will say that these robotic chess pieces are larger than typical chess pieces. But they aren’t that much larger and the robots are still very small. When each piece of the board is a robot, chess can play itself and that’s an improvement.

As you’ve probably guessed, this was a big miniaturization challenge. Each piece needs its own power source, motors and drivers, communication capabilities, and ability to determine its own position on the board. Oh, and 3DPrintedLife had to make each robot affordable, because a game of chess will require 32 of them.

He pulled that off by designing a custom PCB, which goes into the 3D-printed body of each robot. It contains an ESP32, stepper driver ICs, power handling, and a magnetic field sensor. Power comes from a little lithium battery and two stepper motors turn little wheels via friction engagement. A central command module communicates with each robot’s ESP32, telling that robot where to go.

But to know where to go, the robot must first know where it is. That’s why there is a magnetic field sensor. Underneath the board, there are three electromagnets creating magnetic fields. With timing in sync (done through ESP-NOW messages) and the electromagnets activating in sequence, the robot can calculate its position relative to each. It is a variation of standard triangulation, just with magnetic field strength instead of radio transmission time.

At this stage, there is one robotic chess piece that knows where it is on the board and can move as commanded. Next, 3DPrintedLife just needs to make 31 more robots and also sort out a whole hive of bugs, and he’ll have a self-playing chess set.