Where the Hackaday Cat goes when she steps over the threshold into the wider world is a mystery, she reveals her whereabouts strictly on her terms and would we suspect be very cagey were we able to ask her about it. [Andy C] however has a need to know where his cat is spending her time, so he’s made a GPS collar for a bit of feline spying.
There are commercial GPS collars for pets, but they all share the flaw of extremely limited battery life. His challenge then was to create a collar that delivered the required pinpoint fix alongside a battery life measured in months. The solution was a combination of a low-power miniature GPS receiver and a low-power PC microcontroller hooked up to an FSK radio whose frequency he doesn’t give but which we suspect is probably the usual 433 MHz. The collar remains in low power mode until it receives a call on the FSK, at which point it wakes up, gets a GPS fix, transmits it, and returns to sleep.
The summary links to a series of posts which provide an extremely detailed look at all aspects of the project, and go well beyond mere GPS trackers for a cat. If you have an interest in low power devices or antenna matching for example, you’ll find a lot of interesting stuff in these pages. Of course, if all you need is a GPS tracker though, you may prefer a simpler option.
Hmm, to track my cat with a 433 radio it would either need to grossly exceed the power regulation or have a Yagi fitted with some sort of point at home mechanism on it. :)
I have seen him well over half a mile away.
Hmm, use LORA then? https://hackaday.com/2017/09/11/the-things-network-sets-702-km-distance-record-for-lorawan/
433 goes quite far and is used in Germany for fox hunting. 10mW, 15mW or 25mW is allowed depending on country but the transmissions have to be intermittent, like in this application. Buy a Chinese garage dor module, they stretch the law to the “limit” and put a 2 or more element yagi on the receiver and you get 5-10 miles range (if your cat stands on its hind legs on a hill top).
Fox hunting? Once you have the animal, one doesn’t need the other half.
Radio direction finding fox hunting, as in, HAM radio enthusiasts competitions to find a radio beacon (the fox) fastest.
Ostracus – I think Tore Lund is talking about RDF tracking targeted humans (in the wind) not animals. Like in Amateur Radio fox hunts?
You could use an omni antenna on the cat and a tracking dish on your roof. At least this would achieve the necessary link budget.
Someone may mistake him for a lollipop stuck in the grass :eek:.
or just use the APRS network with a low power radio that also only wakes up when recieving a strong enough signal on the tiny antenna to be sure that the transmission the other way would be strong enough
Reading for a few minutes, i found this part of the text: “I’ve written some basic code in the PIC that tells the CC1125 to output a Continous Wave (CW) at 868 MHz, to allow me to take my measurement” – So not 433, but 868 MHz.
Free range cats and collars are probably not the best idea.
They can hurt themselves when they get stuck with the collar on/in something. Like a hole in a fence or something.
ive found that if a cat doesn’t want to wear a collar they will find a way to loose it in the woods. this is especially true of those break away collars, which seem to disappear within the first week of use. i certainly wouldnt want there to be any expensive electronics in there when it happens, unless of course it transmits its position.
Glue it to its fur!
“Glue it to its fur!”
Why not just glue the cat to the floor? That way its position can be verified at any time with a simple web cam. };¬)
+1 !!!
But then you’ll lose out on its momentum information! ????
Looking at the bright side of it, you can find where the cat is stuck at a push of a button.
Free-range cats without collars are strays.
No RFID transponder?
That’s at least what we use in Germany
No cat is a stray.
If a cat decides it needs a home, it will find one and invite itself in. If not, it will live where it wants to.
Maybe some kind of dorsal vest ???
we suspect if you did a little more reading on the post you’re linking, you’d actually find he tells what frequency he uses…
I suspect that if you read the other replies before posting you would see that it has already been stated.
we suspect you have no idea how long a comment can hang around ‘awaiting moderation’
i was going to use the usb cable gps gsm tracker from ali express and add a battery
Is moggy a British term for a kitteh cat?
Kittat is an arabic term for cat…
.. or a Morris Minor, so be careful to get clues from context… i.e. my moggy needs a new bonnet, or my moggy needs it’s wings brushing out etc.
I have trouble figuring out which of those two examples is the cat, and which is the car.
Cats don’t wear bonnets, and cars have hoods. :)
https://www.google.com.au/search?q=cat+bonnet&tbm=isch
You were saying…? :D
Curses! The Internet (a treasure trove of photos of cats doing implausible things) has foiled me again!
Do you mean PIC microcontroller?
months of battery life? that thing needs to monitor the band ~continously, you cant even get a portable FM receiver able to work >week in that form factor.
Reception can be as low-power and as low duty-cycle as you need. It doesn’t need to be “continuous” at all, you just make the transmitter side send it’s ‘wakeup’ signal long enough that the receiver is guaranteed to have woken up at least once to see it.
Gene Brensfield did a pretty indepth Talk at Defcon22 about how he build an arduino-based “wardriving-collar” for his cat.
https://www.youtube.com/watch?v=DMNSvHswljM
You could also wire your cat for sound like we did in USA back in the 1960’s. Then you could track it with a turn-able base station Yagi Uda antenna. We called it Project Acoustic Kitty. Turned out to be a real epic fail though:
https://allthatsinteresting.com/wordpress/wp-content/uploads/2018/06/acoustic-kitty-wiring.png
Another way to track kitty without weighing it down is to attach a low-powered ultrasonic beacon like a belled cat. Then send up an autonomous quadcopter (AQC) drone with a tracking ultrasonic receiver to go look for kitty. Just make sure operational frequency is well above 45 KHz as kitty can hear up to that frequency.Or if you can’t afford a AQC then place a bunch of field solar powered IoT’s throughout the neighborhood to report ultrasonic hits back to your website. Then it reports back to a website it’s pre-assigned fixed location. Disguise the IoT’s like the animal poop (or a rock) VHF transmitter seismic gadgets used to report North Vietnamese troop movements to the Americans during the VNW (i.e. Operation Igloo White). This is to stop people or animals from messing with your IoT gadget. (Or some creative variation on this theme)
Animal poop disguise: https://goo.gl/BEbQ17