Window-wiper motion

[MrCamilleri]

We're a rookie team (6070) and we are trying to design a mechanism to raise an arm from a horizontal position to a roughly vertical position and back again, like a window-wiper. Ideally this is with the push of a button. Next we want to be able to retract the arm back to the starting position, with another button.

The force needed should be relatively low, as we are simply raising a square-extruded piece of aluminum.

Do we use a motor with some kind of shut-off switch that is tripped once the arm is in the desired position? Or should we use a pneumatic actuator? Or is there a servo that can do this for us?

Any kind of direction is appreciated.

Thanks,