I always wanted a piece of Star Trek and the Disney Monorail in my house, and one thing they have in common is that they both have automatic sliding doors. It would be the perfect, most geek-ified entryway for my bedroom.
Edit: Not every detail is included in this Instructable. I did the best I could using pictures I had taken 4 years ago. There are some more details on my blog if you would like to read more: http://uiproductions.blogspot.com
To be acceptable as a permanent renovation to our house, I knew the door had to have a normal appearance, as well as be practical and maintenance free. To reduce the number of moving parts (and maybe for a little coolness factor) I decided to make the door air-powered. The air would be supplied by a small compressor and storage tank located in the attic. In order to open and close from the inside and out, the door needed a little bit of brainpower. I decided to use a small PIC microcontroller, my platform of choice still to this day. Arduino didn't exist back then.
With a rough plan in my head, I drew a quick CAD model of the door and the brackets that would connect the pistons to the door halves. I was ready to start purchasing parts.
Step 1: Buy Parts / Tear Out Wall
Here are some of the parts I used:
- Craftsman 1 Gallon Air Compressor / Tank
- 32" wide, solid wood door from Home Depot (to be cut in half)
- Pocket Door Track from McMaster.com
- Two 16" stroke, 3/4" bore pneumatic pistons from McMaster.com
- A 5-way, 12V solenoid-operated valve from McMaster.com
- Various pneumatic hose, fittings, a regulator, push-on hose connectors, two valves for air supply and purge
Your parts will vary depending on your door size, your wall configuration, etc.
Start tearing out your wall with a hammer, crowbar, or any other destructive tools you can find laying around. This is the fun part of the project!
- Craftsman 1 Gallon Air Compressor / Tank
- 32" wide, solid wood door from Home Depot (to be cut in half)
- Pocket Door Track from McMaster.com
- Two 16" stroke, 3/4" bore pneumatic pistons from McMaster.com
- A 5-way, 12V solenoid-operated valve from McMaster.com
- Various pneumatic hose, fittings, a regulator, push-on hose connectors, two valves for air supply and purge
Your parts will vary depending on your door size, your wall configuration, etc.
Start tearing out your wall with a hammer, crowbar, or any other destructive tools you can find laying around. This is the fun part of the project!
Step 2: Install the track, hang the doors, and patch up one wall.
I proceeded to cut the solid wood door in half with a circular saw, sanding the edges when done. I considered using bi-fold doors which are already the right size, but they didn't give the appearance of a normal door when joined together.
With all of the interfering studs removed from the wall, I held the rear drywall in place with 3/4" thick wood boards, which would still leave room for the door to travel through the wall. I added a new 2x4 stud on one side to support the pocket door track, and installed the track and a door half using the included hardware. You can see below how the one half will slide into the wall cavity.
Some strips of drywall, mud, and trim take care of the hallway with no problem.
With all of the interfering studs removed from the wall, I held the rear drywall in place with 3/4" thick wood boards, which would still leave room for the door to travel through the wall. I added a new 2x4 stud on one side to support the pocket door track, and installed the track and a door half using the included hardware. You can see below how the one half will slide into the wall cavity.
Some strips of drywall, mud, and trim take care of the hallway with no problem.
Step 3: Fabricate door bracket / install pistons
Next I had to fabricate a bracket to connect the pistons above the door to the actual door. I welded up a bracket out of some steel flat bar from Home Depot and attached it to the back of the door with a spacer block. I could have really used some more advanced tools at this point, but I had to work with what I had at the time. You can fabricate this bracket from sheet metal, steel bar, wood, or whatever you can find.
With the two brackets fabricated and installed, I mounted the two 16" pistons above the door, side by side. Air supplied to the back of the pistons would open the doors, and air supplied to the front of the pistons would close the doors, as seen below. I rigged up the valve temporarily to test everything out.
With the two brackets fabricated and installed, I mounted the two 16" pistons above the door, side by side. Air supplied to the back of the pistons would open the doors, and air supplied to the front of the pistons would close the doors, as seen below. I rigged up the valve temporarily to test everything out.
Step 4: Electronics
For the electronics, a simple on/off switch would have worked. But I wanted to get a little fancier and control the timing of the doors opening and closing. I made the circuitry from components that are readily available at Radio Shack and Sparkfun.com. The circuitry just waits for the button to be pushed then switches the air valve on so the door will open. After a few seconds, the valve switches back off and the door closes.
I mounted a DIP socket, a relay, and a few other components on a Radio Shack perf board, and placed the whole thing inside a plastic junction box. I also wired in two AC power switches, one supplying AC power to the wall adapter for the circuitry, and the other supplying power to the compressor in the attic. I wanted the whole system to be enabled and disabled from this "control panel", including the air supply.
I mounted a DIP socket, a relay, and a few other components on a Radio Shack perf board, and placed the whole thing inside a plastic junction box. I also wired in two AC power switches, one supplying AC power to the wall adapter for the circuitry, and the other supplying power to the compressor in the attic. I wanted the whole system to be enabled and disabled from this "control panel", including the air supply.
Step 5: Test it out / patch up the wall
After countless cycles of testing and tweaking the door operation with the wall open for a month or two, I finally felt comfortable closing up the wall. Here you can see some of the new drywall starting to go back up.
From there it was just a matter of painting the wall, and it was back to looking stock. I purchased a blank white wall plate from Home Depot. I drilled it out for an illuminated pushbutton and a 3-position keyswitch, both of which I bought from McMaster. I also purchased a plastic hatch door from McMaster for the control box. Lastly, I added an air conditioning vent above the door. This lets the air venting noises be heard, and it also provides me access to the valve and pistons should anything go wrong.
After you've tested the door and patched up the wall, that's about it! Good luck with your project and feel free to post comments and ask questions if I skipped over anything you might need help with. Thanks for reading!
From there it was just a matter of painting the wall, and it was back to looking stock. I purchased a blank white wall plate from Home Depot. I drilled it out for an illuminated pushbutton and a 3-position keyswitch, both of which I bought from McMaster. I also purchased a plastic hatch door from McMaster for the control box. Lastly, I added an air conditioning vent above the door. This lets the air venting noises be heard, and it also provides me access to the valve and pistons should anything go wrong.
After you've tested the door and patched up the wall, that's about it! Good luck with your project and feel free to post comments and ask questions if I skipped over anything you might need help with. Thanks for reading!
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great job, could you come to my place and do one for me :)
we dont have this technology here on erf... YET.
but in the meen time, I would imagine a infra-red motion sensor would be too much of a PITA for this scenario, however, a floor mounted pressure switch could be advantageous.
I just spent the past 10 minutes reading every comment and i have one thing to say to any one complaining about saftey first you obviously didnt watch the video but mainly secondly its wood with no centre connection meaning a weak point all you would have to do is simple firm kick to the centre and you have effectivly made a entrance the doors are not that strong.
ps on a side not dr who how many jobs have you done since you must be 250 years old to have mastered everything.
thank you so much for sharing this one!
P.S. don't mind Dr. who he was bugging me also
Hats off to all your work :)
*xkcd reference
The "return action" of the Star Trek Turbo-Lift doors didn't really have a sound to them (until much later in the series that is). So, perhaps the "return spring" method of closing isn't such a bad idea.
The thing I find dangerous is that you didn't incorporate any kind of "Manual Override" in your design. Since you're using compressed air as the actual power for the door pneumatics you wouldn't need electrical power in an emergency. Just a bypass valve in one of your access panels or add a new panel or two. One for both sides of the door, because you never know what side you're going to be on when power goes out and you need to get in (or out) of the room.
Also, if you're thinking that a battery backup will suffice to answer these issues, you're just begging for problems. Battery powered UPSs are notorious for having the battery go bad from non-use. Yes I said NON-use. Plus the power that compressor takes at start-up will just pop the weak little breaker on the UPS leaving you still stuck on one side or the other. So I wouldn't bet my life or my kids life on a $50 UPS you got at Best Buy.
This is a mechanical device and it should have a manual bypass. Seems to me that this is a no-brainer and all that's needed is a couple 1/4turn ball valves and a couple anti-reversing valves installed.
A "Neat Door" is not worth dying over because you cheaped out. In my opinion, there is never a "Good day to die".
This is very cool though. There are still other things that you could do to it. Like add an RFID system or Thumb-print scanner or freak out your friends with an Ocular or Handprint Scanner to open the door! How about Voice operated command system or just a simple contact pad (like in the grocery stores) or a short range motion detector to activate it.
Also, there is a "single ram" method to open both doors that goes hand-in-hand with the "spring return" closure, using a thin cable and a couple small pulley-type wheels. Super simple design uses only 1 air line to the ram! This would decrease the cost and complexity of the build by a factor of 4 (don't ask, it just sounds good). So, you could have done either 2 doors with the parts you now have or just saved youself from buying the second ram, the extra hosing and fittings and the time it took to install all that extra stuff.
If you're interested, PM me and I'll send you a drawing of the modification.
These are just some things to think about.
Good job with the instructable. I liked it and so did a bunch of other people!
2. So you actually made a drawing of a random modification to someone elses project, yet you decided to skip the video and go right to the instructions for fear of wasting time? lol
2. I didn't make a drawing. It says "PM me and I'll send you a drawing of the modification". Meaning I could draw it up, not that I drew a picture for him.
&
"These are just some things to think about." You must not have read that last line...
And I did watch the video, after I read threw it, but all the suggestions I made are based on first-hand experience with the different technologies involved with the controls and mechanics of automated doors.
And as I said, the video wasn't all that useful. it just showed the final product in action but it didn't show the build process. But he had a lot of nice pictures that did. So watching the video first wouldn't have given me the information I was looking for.
Just because something is at the top of a page, doesn't mean you HAVE to start there. It's just a suggestion.
So thanks for trolling.
Having two cylinders was the simplest option for me at the time, not having any fancy tools to fabricate a pulley system. I don't understand how adding two pulleys, a cable, and brackets would simplify things more. They are both equally good options in my opinion.
A battery backup is just a convenience. If the power goes out, the door will still function normally. It doesn't replace the manual override or the fact that you can just force the doors open by hand if you need to get in or out, which I have done before. I wouldn't be buying a UPS from best buy, I would design a PCB for battery management. That's what I do for a living now.
Nobody is dying because I "cheaped out". If the power goes out, there is a manual override. If the compressor doesn't run, the lines will eventually lose air pressure and the doors will be even easier to open by hand. And heaven forbid, if the door doesnt open and the room is on fire, just climb out the window that's two feet away, don't be stupid.
But seriously, there are always going to be more "nice to have" features. I built it to be practical and unnoticeable, which it is for the most part. I don't even live in the same city anymore, and the door still works great 4 years after I built it. It saves space, it is easy for ANYONE to operate, and it looks cool! There are plenty of other uses for it to, such as in homes of people with disabilities.
Thanks for the constructive criticism.