Hello arduino forum,
I would like to recognize a horse when its head sticks out a window to eat some hay.
I was thinking about using RFID low frequency, with passive tag. But I don’t know how to building my own antenna, which will fit the window.
Thank you in advance for your help,
David
Using a light bar could be a solution. Then the poor horse doesn't need to be "decorated".
I would use a break beam sensor.light on one side, sensor on the other, below the top of the French door so it trips when he dips his head.
Do you need to differentiate between different horses, or not?
That horse
() is really dead.
() has already bolted.
(x) is a different colour.
() was a gift.
() can reach the other side of the stream perfectly well.
() won't drink.
() is not a unicycle.
() is a horse, of course, of course.
() is wooden.
() is not really very high
() is behind the cart
So maybe a camera running OpenCV?
Edit: often antenna solutions involve a little trial and error to be optimal, however with the idea of a loop that resonates close to the RFID frequency, next to or around the opening, you should get close up sensitivity at least.
I suspect you would get more useful advice with a meaningful title such as "Detect when a horse sticks its head out"
If you modify your Original Post you can change the Title.
...R
Interesting project. Industrial solutions exist that can detect a passive tag moving through a doorway, so I imagine that you can emulate that with an antenna around the edge of the window. The usual RFID projects here are using low power and low range (a very few inches) so you may well need something more substantial.
If the horses are always wearing a halter, that might be a place to fit the tag, but is that the case with yours?
Assuming you get it working, what are you going to do with the information that Dobbin stuck his head into the manger sixteen times today but Black Beauty didn't eat at all? Furthermore, how are you going to do the analysis? Machine learning?
Thank you @Robin2 for your title suggestion, I edit so.
aarg:
So maybe a camera running OpenCV?
I have two horses that have the same color (black)... also during the night, with IR vision I can barely differentiate 2 horses based on color or shape.
wildbill:
If the horses are always wearing a halter, that might be a place to fit the tag, but is that the case with yours?
I was thinking about 2 things :
wildbill:
Assuming you get it working, what are you going to do with the information that Dobbin stuck his head into the manger sixteen times today but Black Beauty didn't eat at all? Furthermore, how are you going to do the analysis? Machine learning?
With this information, I could deduce how many kg of hay they eat (they always eat the same amount of hay per hour as I can see). With this I could adjust how many food supplement (oats, alfalfa, etc.) I need to give them (using another home made machine, but this is another story).
So when Black Beauty don't eat today, I know I need to find a solution (maybe his sick, or he cannot access to the hay because of other horses). If Dobbin is too big because he's eating too much, I could close the door so he cannot access anymore to the hay. 
The frequency is 134,2kHz. I know that building antenna for a specific frequency is not trivial, and I don't know how to do it.
That's why it's important to know how much research you've already done, so we don't waste time in repetition. Generally, it will be a loop antenna, it will have multiple turns, there will be a capacitor (sometimes tuneable) in parallel with the coil to make it resonate at 134,2kHz.
What does your transceiver/detector circuit look like? Any particular reason you're home brewing it instead of just buying an RFID detector module?
I did Google, "DIY RFID antenna" and got lots of hits...
I found this one on Aliexpress 125 134.2KHZ Animal Tag Reader Module TTL Output AGV RFID FX B ISO11784 Long distance+2 tags|tag reader|tag tagtag rfid 125khz - AliExpress.
But the antenna is only 10 cm long. That's why I want to build the antenna myself, to fit the edges of my window.
Also, when I was looking on google I didn't really found one that can fit my window. And most of results it's for 125kHz antenna. I don't how I can adapt a 125kHz antenna to 134,2kHz?
davidlivet:
I found this one on Aliexpress 125 134.2KHZ Animal Tag Reader Module TTL Output AGV RFID FX B ISO11784 Long distance+2 tags|tag reader|tag tagtag rfid 125khz - AliExpress.But the antenna is only 10 cm long. That's why I want to build the antenna myself, to fit the edges of my window.
Also, when I was looking on google I didn't really found one that can fit my window. And most of results it's for 125kHz antenna. I don't how I can adapt a 125kHz antenna to 134,2kHz?
You linked to "125-134.2KHZ Animal Tag Reader Module" which you can place under, or to the side of the window.
They say the detection is about 10-20cm, and I'm afraid that is not enough to trigger the tag.
davidlivet:
I have two horses that have the same color (black)... also during the night, with IR vision I can barely differentiate 2 horses based on color or shape.
OpenCV is a lot better than you at detecting different animals. Don't be so fast to discount it as a solution.
RFID is not likely to work as you imagine. The theft-detection systems in department stores are very expensive. The RFID of cars at toll booths are priced in the hundreds of thousands of dollars. RFID that the average hobbyist can afford has a range of a few centimeters.