Laser clock that draws the time using an Arduino Uno
Used a CO2 laser cutter to cut out 1/8" clear acrylic pieces. You can also use a 3d printer using stl files.
Arm movement shown. These cheap 9g servos use pulse width modulation (PWM) to move the motors to the desired angle. They can rotate 180 degrees.
An NPN transistor was soldered onto the ground wire of the laser.
This is the final result of version 1.0
I have gone on to make two more version with the STL and DXF files posed on thingiverse here:
You can even follow my guide here and build your own!
Nice! I've seen these before, but yours has a nice smoothness to the mechanism that makes the writing much more legible.