A small explanation on the project. Im building several circuits to improve the quality of life for my girlfriends 2 rabits in the shed.

I have almost completed a thermostat circuit (currently not working but it will do) from http://www.unusualelectronics.co.uk/...mostat_cct.gif

this turns on a 12v DC fan, and I plan to use the rpm signal wire to feed a mosfet through a smoothing cap that will turn on a 12v 15w PTC Heating element to take the frost off on a cold night providing the fan is functioning.

All these shed circuits are solar powered so efficiency is key. I'm also planning to make a tunnel from their home to an outside enclosure so they can run about when they want to.

Now I would like to have an electronicly operated slide door to prevent the rabits going outside during the night and in turn stop the wind blowing up the tunnel and into the hutch. Here my problem lies:

Im not sure where to start as I need to make sure both rabits are inside before closing the door! I was thinking 2 infared sensors, named A and B, if A then B are activated it is a rabit going out, if B then A its a rabit comming in. There are 2 rabits btw.

I want to close the door if one of 2 conditions are met, it is beyond a preset time say 8pm or it is cold (coult interface the above thermostat circuit some how to test if it is cold)

I'm thinking this will be way to advanced for me but who knows, you guys might have a very simple idea to lead me in the right direction.

Thanks in advance!

 

maybe a flap instead that shoots a bolt on the outside preventing going out but not in....

 

Don't know why the night/day would matter... If it's too cold for them or raining, they'll stay where it's warm and dry, unless they are defective... Just use a hinged flap door with a magnet to hold it close from the wind. No battery power required. If you provide them with a box (wood) and nesting material, they'll be fine without a heater, unless it get could, like northern canada...

 

The heater, as i say is to take off the frost so it wont be on untill its about 4-10 deg C.

They have a "box". You could ask "why bother" for alot of projects but that isnt the point, its a challange and my girlfriend wont let me stick electronics everywhere in the house so currently im confined to rabit/shed related stuff.

 

The heater, as i say is to take off the frost so it wont be on untill its about 4-10 deg C.

They have a "box". You could ask "why bother" for alot of projects but that isnt the point, its a challange and my girlfriend wont let me stick electronics everywhere in the house so currently im confined to rabit/shed related stuff.

 

That idea occurred to me too, but it might be difficult to ensure that 2 rabbits going out or in at the right speeds and the right distance apart couldn't make the system think, say, that one rabbit was going in or out.

My first thought was a microcontroller (say, an 8051 variant, a PIC, or an AVR) with a thermal sensor and what we'll call a Rabbit Detector, which tells you where the rabbits are, but that might be overkill. Everyday diodes can be used as thermal sensors, but I don't know off the top of my head if they do this well in the temperature range you're looking at.

As for the Rabbit Detector: I can't really think of anything reliable short of RFID tagging them somehow, but that might screw up the solar power energy budget. And if the gf doesn't want you putting electronics around the house, she may balk at electronics on her rabbits.

Ultra-simple idea: can you train the rabbits to go through a cat flap if you stick one at one end of the tunnel? If so, that leaves you with only the thermostat problem and the door problem is solved with no power drain. If the rabbits are cool with going through a cat flap, then they'll go inside if it's too cold outside.

What kind of rabbits are these? Many kinds of rabbits handle harsh winter conditions very well.


Just some thoughts + good luck!

Torben

 

Hi, thanks for your reply. Seems it will be a bit too complecated to track the rabits in/out. I doubt I can RFID the rabits lol - How about a chip below the skin lol anyway I think I might have to just make do with a flap, If I turn it 90deg towards the fence then it should stop the wind blowing up the tunnel too much, together with a flap it might stop it all together.

One rabit its a netherland dwarf and the other we are not sure, a something giant lol (I didnt choose) They are usually in the house for most of the night to run about and chew my wires/cables so they are kind of house trained and I feel really bad putting them out in the shed on a cold winter night... its only 15w so I wont cook them.

now onto the rabit lift... joking

 

You could use a PIR to detect any rabbits in the outside enclosure.

 

actually, you can get pretty small rfid tags - they use them on all sorts of animals. I suspect your biggest problem there is getting your GF to agree to let the tags be inserted in the rabbits. Their ears probably have lots of room.

 

Yeah, I think I know the answer before I even ask. Or, I could insert them anyway and just lie "this is a special circuit, it only detects rabits due to their special DNA" that should be enough to baffle her.

PIR is an interesting idea, would it pick up small reading from a rabit?

Just thought, how about a infa-red beam across the outside of the flap, if it is locked it opens when the beam is crossed, rabits can get in but can't get out. How that would be put together im not so sure.

 

I'm no rabbit expert, but could you put a collar with a magnet on the rabbits and then detect them with a Hall effect device?
Another idea would be a platform in the tunnel that weighs the rabbit when it steps on the platform. You could have a weight window for one or two rabbits. Or just a simple spring tension/micro switch setup.

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I hope you're not thinking of making the heater solar powered as it would take far too much power, which won't be available in winter.

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It is solar powered its rated at 12v 15w, not a show stopper in the solar world