This video is simply mad, but in a way that deserves a few seconds of your time. Watch as it counts down the seconds until it can erase a digit. It almost has personality.
Perhaps we are in a time when robotic hardware can be used just because it can.
What about a clock that writes the time on a board using a marker pen?
Ah I hear you say, what about when it needs to update the time?
Simple, it has an eraser.
Yes it is simply mad but in a way that deserves a few seconds of your time to view the video - it is very cute. Watch as it counts down the seconds until it can erase a digit. It almost has personality.
Now that you have seen it the technical details should be easy to see that it's based on four standard servos. The controller is an Arduino and the reason that the writing is a little shaky is that the servos have no positional feedback to the Arduino and so positioning is by dead reckoning. The designer, Ekaggrat, thinks that switching to stepper motors would produce a more accurate writing style. This is undoubtedly correct but would it indeed be better?
Personally if we are throwing hardware at the problem, I think I'd add a Kinect and use that to provide some feedback to the dead reckoning of the servos.