It looks amazing! How is actuator travel distance which compensates differences between the heights of the chess pieces implemented?

It's hard-coded at the moment. I just measured the height of each piece and stored the values.

To me it looked like the clearance height was the same for all pieces. Is it actually dynamically calculated for each move?

Ah yes clearance height is the same for all pieces, the servo raises the piece to the piece height + the "resting" height. Relevant code can be found here:

https://github.com/joeymeyer/raspberryturk/blob/master/raspb...

Can you comment on the safety aspects of the design? It seems possible that the robot arm could collide with the arm of the human player, or that an unlucky player's finger could get caught in the robot's elbow joint as it closes.

Maybe don't stick your finger in the robot.

The design of the system requires the player to put their hand in the robot arm's work envelope in order to make a move, so in order to follow your advice one would have to avoid playing the game, which seems a shame.

The robot actually moves much slower than the speed in the video, so it would be hard to get caught without trying. The servos are also weak enough that they wouldn't be able to really hurt you.

Unless it's a physical limitation of the motor, "moves slowly" is still risky, because a programming error could cause the robot to move unexpectedly quickly in an unexpected direction! But "motor too weak to cause injury" is a good safety feature.

The project looks really nice in the videos, by the way — it must have taken a great deal of effort to get it working so smoothly.

Have it listen for j’adoube and fold up out of the way

Congrats for such a great project! Does the robot can promote pieces by itself?

Thanks! No at the moment the robot just places it's pawn the last rank. You have to watch the status page on screen to see what it promoted it to. Definitely need to come up with a better way to do that.

Awesome project joey, the documentation was neat.