I have a niece that has asked me to build a project for her special needs son as a Christmas gift. He is currently fascinated with automatic garage doors. She provided this video to me but it does not include many details. https://www.youtube.com/watch?v=xnAvMjC7N90
I can handle building the structural part of the project but am asking for help with the motor that would drive the door. Can anyone suggest to me what DC motor and switches to use for this project? It seems to me that I would somehow need to reverse the polarity of the motor to get it to run in both directions. I am unsure how you would get the motor to stop when the door would reach the completely open or completely closed position (possibly some relays?).
Any suggestions would be appreciated. Thanks,
In the video linked, there’s a DPDT switch that changes direction and a momentary button that starts/stops the motor. There’s a disadvantage to this in that you can hold the button down and run the door past full open and full closed. It works, but you have to be careful to let go of the button in time to not damage the door.
I did see a recommend video link to a different design that uses a DPDT switch and two SPDT limit switches and that has a schematic at the 5:28 mark that should work for you. In that design, you flip the direction switch up to raise the door and when the door gets to the top of the run it opens a limit switch. When you flip the direction switch down, the door lowers until it hits another limit switch. The limit switches cut power to the motor so that you don’t accidentally overshoot the top or bottom of the door.
The video is here: https://www.youtube.com/watch?v=3hEipRDH3_o and a pic of the schematic is below. There’s LEDs in the schematic but those are optional.
Thanks a bunch. This will work.
