Well… Circle of Complication is in full design/debug. Turns out it was named correctly. I’m learning things about motors I would rather have had not. The final design of this piece has one stepper motor, one DC motor and two servo motors. The stepper motor has turned out to be quite a little riddle to solve. I’ll spare everyone the details on that one, but I had some issues that really took work to solve.
Main board and stepper driver
DC drive motor and two servos
Stepper motor on mount
Main arm with actuator and DC drive motor in layout
That last photo is the linear actuator on a board that I drew a 1″x1″ grid on for layout. The blue wheel on the top left is the main drive wheel. The stepper motor mounts on this linear actuator to slide the pens back and forth on the arm. As the drive wheel turns the whole arm, the actuator goes in and out, changing the effective drawing radius. I can also control the servo motors which are what hold the pens and actually make the drawing. The overall arm swing is about 30″ so the base will be 60″x60″ wide. This is a big piece.
Fabrication of the mechanical portion starts this Tuesday. Will post pictures soon.