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Automatic Solar Dog Door Opener Answered

I have a dog door (http://www.hartleyglass.com.au/images/pet-door/pet-door3.png) but my dog is a bit anxious about opening the door with his head. I can't say that I blame him really.

So I want to attached a solar powered device that would open when he is near by.

I imagine I would mount it above the black bar, outsize where the is light with the solar panel wedge, attached to the door (see image uploaded). 

I don't really know how to go about it. 
The major components would be:

1. Solar panel wedge and batter (power source)
2. Proximity sensor (maybe RFID attached to my dogs collar?)
3. Motor (not sure how to detect when the door is opened or closed. etc etc 

How does one go about building something like this? Any direction would be great



Why "solar powered"? Will he be able to "get in" if it clouds over etc. The best solution to "opening" when he is near is a proximity sensor; either one that senses using IR light or senses a change in electromagnetic force nearby (A living body). There are several options there too.

I suppose solar to charge a battery so that I don't have to keep replacing them. That's all the battery should still have a charge. How do I go about building the circuits and stuff? That's where I'm most stuck.

Battery chargers must be engineered for the battery used. A NiCd for instance will not LIKE to be discharged and then partially charged; if it is used before full charge, it;ll gain a "memory" and will not charge beyond that point. If "overcharged"; it could leak, explode, or generally fail. SO, if using NiCd's, you need to wire the circuit to sense a full charge (in order to stop the charging) and a fail safe that will not allow either full discharge nor partial recharges........it's a tall order, but this is the kind of thing used in those industrial emergency lights you see hanging in some buildings. I am not very familiar with the recharge methods of other batteries.

I wouldn't go for a vertical slider, they're mechanically complex and inclined to jam - there are reasons why cat and dog flaps are flaps. Motorising it would be best done with a rubber belt drive, so that, if he ever does get himself together, and butts the door, he won't shear off the gears in the motor and/or hurt his head. The belt drive could be arranged to slip when its backdriven.

Also, with RFID, you're going to have to have two very well screened antennae to detect him on one side or the other, and switch between them.

Alternatively, you could use reflective optos, or PIR attached under the "hood" of your device.


The easiest thing may be to change the doggy door so that instead of swinging open on a hinge, have it open up and down instead. Then you could use a motor with a string to simply pull up the door and let it back down.

For entry/exit, you could use a motion sensor, if you're not worried about other animals triggering it and coming inside. If you want it to only open for your pet, then you'd want a key-fob type thing for your dog's collar to trigger the motor to open and close the door.

I hope that helps. :-)

Why is pulling up better? I guess that I'm more stuck at the electronics part of all this. How do you hook up all the parts?

ahah thanks.
I checked and the door doesn't flip around. When it's upside down it doesn't fold all the way down to the ground so it's impossible fro any dog to get in or out.
Thanks anyway

I think lucidwayn wants to keep it hinged because that doesn't require changes to the mechanics of the existing flap he/she's had installed.

It sounds like you're over complicating the problem. Can't you teach your dog to just not be anxious about it?

I wish. We have tried everything. He would rather sit outside and bark his way in then butt open the door. Beside he thinks he is a person and would rather just use a normal door. Imagine if you were on your hands and knees and some made a door for you at the bathroom and you had to bang your head against every time you wanted to do a wee.

We have automatic doors everywhere. Why can't my doggie have one?


Have you been to see a behaviorist? Dogs are smart when trained right.

If you still want an automatic opener, you have a few options electronics-wise. How complicated do you want it? Why solar?

If you just wanted a button either side for your dog to press then the only electronics you'll need will be a motor, 2 limit switches, 2 buttons and a power supply.

If you wanted to get really fancy you could have it RFID activated so only your dog could activate it. That way other animals and objects wouldn't set it off.

yeah I get all that. I just don't know how to link all the parts together. e.g. circuit boards and that kinda of stuff. do you know how?

Yes, but I don't want to draw you a sketch one way if you want it done another way. If you just want buttons, limit switches and a motor it's a 5 minute sketch. If you want RFID it's considerably longer and the parts cost more. Considering your electronics knowledge it might be easier for you to put together the non-RFID option.

okay cool. I'm really up for a challenge. I'm a programer so hopefully that helps a bit.

I think a RFID but I have no idea how much they cost.

I don't mind a proximity sensor either:

there are RFID components but seems to be quite expensive.
Is that normal?