New support method and mechanism made. First was difficult to install and align. 


Controller and mechanism for a projector screen.

Joystick proportional control with audio feedback on limits and on-reminder. 

Electonic limit adjusters for raised and lowered extents.

Latest addition is an anti-sag feature, needed because there is creep in the screen hardware - after a week it is noticeable that the shaft has bowed slightly. The solution is an added switch to record at setup, the difference between fully raised and lowered by a 180 degree turn. In use after this, each time the screen is raised it will stop at either the fully raised limit or the reduced limit, alternately. To operate only this function, the controller will be switched on, the screen lowered 200mm and then raised.


Switch on and adjust with vertical joystick control. Motor rotates the screen spool via pulley wheels until limit is reached at either end, feedback into the controller to halt rotation in that direction and sound a high or low beep. The feedback is from a potentiometer driven via gearing from the spool. When the joystick is in the central position a middle-tone beep sounds as a reminder to switch it off.


Two pictures of the new support and mechanism:




Prototype, basic controller: