I am looking to construct a timed door opener/closer using a Arduino Uno with a motor shield, I will be using a motor from a screw driver. I have read about people doing this with photocells but not with timed control, has anyone done this and could you share the code and any wiring diagrams.
Screwdriver motors are HIGH CURRENT. You cannot expect one to work from
an ordinary motor shield.
The first task is to size your motor (ie determine how much power/torque/rotation
speed you actually need). Then choose an appropriate motor and driver.
This means working out the mechanics (as in maths) of the setup. Do you have
some sort of diagram of how the door works? Any idea of the forces needed? (enough
to open close the door, but not enough to crush a chicken, basically).