Not sure if to put this here or in CS but…
I work with a theatre company and soon we will be putting up a “horror” play with doors that open and close (slam) by themselves.
Yeah, how do that?
How about a spring loaded door, with a rope and pulley to open from offstage. Pull on the rope to open, let go and it slams. As long as the rope is hidden behind the set it should be invisible to the audience. Anything else I can think of is a lot more complicated and pricey.
It’s easiest to have the doors swing outward, i.e. away from the audience. Then someone can just stand behind it to open and close it.
Well two of the doors I’m building, so I’ll do that. There is one built in door to deal with though.
I have made many a secret door / haunted passage door slam sets in my time. They have ranged from a stick and string operation to pneumatic pistons. Not knowing budget, set design, backstage help, or anything else I would keep it as simple as possible.
Having the doors open offstage and just operated by a stagehand is by far the easiest, but lacks a certain punch, since the audience knows how you did it.
If the door opens onstage a slam can be done by getting the strongest fishing line you can, before it can be seen by the audience. Attach it to the top corner of the door with a small eye hook, use eye bolts to change direction until it is out of sightlines , then make the switch to a rope that is easier to pull. The eye bolts work better than pulleys because fishing line is too thin and will just muck up the pulley.
I did this on a huge chain link door, so it can take the weight of a regular size door.
If you can give me more details I might be able to help out more.
What’s your budget? Actuators ain’t cheap…
Ever used an Arduino before?
If you tilt the door slightly you can weight it to accomplish the close part. Then use the string for the open part. If fishing line isn’t strong enough alone, you can probably braid a couple pieces to increase strength w/out a huge increase in visibility.
I was in a play once where the set was the inside of a house. The “front door” had a nasty habit of opening by itself. We had a guy whose sole purpose was to stand behind it and keep it closed.
Low budget. Thanks for the suggestions so far. I start building the set on Monday. I’ll keep you posted.