Electronic pet doors.

[3v0]

Yesterday I replaced the screen in the patio door. Today we had a thunderstorm and my dog ripped it to get into the house where she feels safe.

I need a pet door that will keep everything but the dog out. The first impulse is to build it from scratch but I already have too may things going. I have the tools and the ability to build the door itself. I imagine the electronics are a RFID setup with a selonid to hold the door shut.

I found the door below here for $160. It relies on gravity to close the door. Will it work when the wind is blowing at 50MPH?
The motorized $600+ units are out of my price range.

Does anyone have any experience with the commercial doors? The kid in me would love to build it. But if I can find a workable solution for under $250 I would rather buy it.

**broken link removed**

 

[HarveyH42]

A little low-tech, and kind of depends on the size of the dog, and whatever else you are talking about keeping out... Just use some strong magnets to hold the door shut. Your dog knows it can get in, and probably strong enough to push a couple of 5-8 lb pull rare earth magnets apart to get in. Most cats and critters, probably not. Should hold up well to the wind. If your dog is a female, and that's all there is between her and a batch of puppies... congratulations. My one year old black lab pushed through the privacy fence, twice now, to get friendly with the neighbors mutt in heat. Don't think he's old enough to shoot live ammo yet. I patch up the fence, and stapled some mesh off old satellite dish. Also, been putting him on a 20 foot chain. Today was the first time he didn't dash over to the fence. Guess the heat is gone...

 

[Optikon]

Don't put the dog out in the storms.. you big meanie!

 

[BaCaRdi]

lol, but then the owner needs to go out with him...bet he has a house...so he sorted.lol

-BaC

Don't put the dog out in the storms.. you big meanie!

 

[3v0]

Optikon and BaCaRdi,
Thanks for the sage advice. She lives in the house but is allowed out on her request into our fenced back yard. She spends about 1/3 of the outside.

Harvey,
The dog is 35-40 lb neutered Keeshond. She does not run away even when the gate is left open. Rare earth magnets might work. I am unsure if I can get her to push hard enough to open the door unless there is thunder. To let the dog in and out it has to swing both ways.

I am thinking that maybe a verticle sliding door operated by an car electric window motor.

Still thinking.

 

[BaCaRdi]

Sure like a horizontal startrek door, that would work, with a pressure or arm type sesor to stop the motor

-BaC

 

[HarveyH42]

I'd be a little concerned about failure of a powered door. The thunderstorms here sometimes cause some weird things to happen. Power goes out, batteries die, motors burn out... Dogs don't understand that kind of stuff.

Remember seeing some rare earth magnets with a hole in the middle, rectangles, on a surplus site. Don't remember which one, but they would be perfect, and cheap.

I use to send my last dog out during hurricanes, even walked him once while the eye pasted over. He was about 130 lbs, so it wasn't that bad. He didn't wander either, don't remember how many times I left the front door wide open and went to bed.

My lab is about 70 lbs now (1 year old), but I'm sure he'd be gone in a flash. He likes to explore.

Anyway, simple and reliable is better for something like this. If you really have to the cool motorized version, I'd suggest using sort of a minimal strength gear motor. One you can turn by hand. If something goes wrong, least the dog might have a chance to free himself, or at least not be seriously injured.

 

[3v0]

When she was a puppy we walked every day. We walked during thunder storms and even while people where shooting off fireworks. She was fine with noise up to her 3rd summer. Could be that as a puppy she figured we were protecting her. As an adult it was her job to protect us and she has no clue what to do about thunder or fire crackers.

You make a good case for a weak motor and low tech. If it is going to be powered it will need a battery backup. Maybe slow charge a 12V gel cell and use it to drive the motor and or ID system.

Maybe the safest way to motorize a door would be to counter balance it so that it slowly falls shut. Use a motor-pulley-cable to lift the door. Reversing the motor would unwind the cable and gravity would pull the door closed. With the counter balance on the door it would not be a problem if the door contacted the dog while closing.

If this works I may want a cat to use it as well. That sort of rules out the powerful magnets.

 

[kchriste]

I imagine the electronics are a RFID setup with a selonid to hold the door shut.

I too have been looking for a simple solution to this. My requirement is for an outdoor pet feeder which only feeds one animal. Same principles apply for the lock and I've come to the conclusion that the magnet on the collar is probably the simplest and secure enough in most neighborhoods.
As for the commercial doors, the cheap ones are just a small magnet on the pet collar which trips a reed switch thus opening a solenoid. That way you at least keep other animals out. Raccoons, squirrels, etc, are pretty smart and will figure out any door without some sort of lock.
One guy went overboard and built one with furry face recognition (fuzzy logic joke):
Flo Control

 

[3v0]

I was under the impression that for a small magnet to trip a reed switch it had to be quite close. Like maybe 1/4 inch. Some doors do use a magnet on the pet color but they may have another way to sense it. Not at all sure.

 

[dknguyen]

Could you jusr use a spring on the door with a lock that is motion activated? So as to unlock the door when the dor is nearby, while the spring does everything else like keep the door closed until he dog goes through (and so the motion sensor and spring together work together to keep out false alarms). Or any proximity switch realy like IR, pyroelectric in to control the lock on a regular springed door.

Really...do you need the door to open on its own? Your puppy probably has more than enough power behind it do that. I don't think you need to bother with it.

Or a doghouse...a really nice doghouse with flapping doors and a corner so the dog can go inside and around the corner (and maybe even a second corner! to get away from the door).

 

[3v0]

We get frequent strong winds that will keep a swinging door or flap from closing. If this happens mice will get into the house.

We have a number of dogs and cats that roam around town in search of food. If the door is not selective there is a chance that they or some wild critter will enter the house.

A dog house is not an option. She is part of the family. She is 7 years old.

 

[HarveyH42]

Might as well give the magnets and swinging door a shot, quick and cheap. You can remove the magnets later or add to it later. Since you want the cat to use the door, try pairs of weaker magnets, and see what will hold well against the wind. You can add more sets as needed. Stray cats won't know they can get in, it'll feel fairly solid to them. Probably won't risk forcing their way in with the scent of a dog and another cat, bad place to get trapped. Anyway, the hardware will be about the same if you want to power it later. A couple of magnets would still be useful to keep it closed. Might be able to use an electromagnet to negate or repel in your design. Should only take an hour or so to layout and install, better then re-screening over and over for now.

 

[killivolt]

Train the dog to lick something. The wet contact of his tongue will trigger the solenoid.

By the way just checking in.

I hope all is well with everyone.

Cheers. kv

Edit : Once open the weight of the dog on the opposite side will close the door from either direction.

 

[dknguyen]

How do mice get into pet doors? Aren't they always pretty high off the ground to prevent that? Just look at the photo someone posted earlier of a pet door.

 

[Ubergeek63]

I actually did quote something like that. It was for controlled feeding of specialized diets in multi pet households. D cells and RFIDs. Biggest problem was powering the latch for that long.

 

[Ubergeek63]

Disclaimer: Avatar for entertainment purposes only.

To quote the Joker: Where does he get those toys!

 

[jbarnaby2000]

How do mice get into pet doors? Aren't they always pretty high off the ground to prevent that? Just look at the photo someone posted earlier of a pet door.

You would be very surprised what and how mice can get into homes...Just recently went through a mouse issue here at my house... It is truly amazing how small a hole they can fit in, and how high they can climb to get into those holes.

 

[3v0]

I actually did quote something like that. It was for controlled feeding of specialized diets in multi pet households. D cells and RFIDs. Biggest problem was powering the latch for that long.

I need to look into RFID. The main question in my mind is range. My guess would be that range depends on what if any antanna is connected to the reciever. Sparkfun has reader modules. The ID card they carry is to large to use with pets. Maybe it can be cut down. There are many other RFID tags/keys elsewhere but I need to figure out what is compatiable.

 

[HarveyH42]

Our security badges at work have RFID chips in them to unlock doors. There is also a barcode for the time clock. One or the other gets damage almost yearly. The door locks only have a range of a few inches. I guess it's a good system for office workers, but the badges get beat up out in the warehouse. Wondering how they would hold up to pets.