Is anyone already working on the PetFinder use case?

(Addy de Jongh) #21

Hi, We are developing GPS trackers for wildlife from small to large for wildlife using GSM, GlobalStar, Iridium, UHF or LoRa for data transfer. Our first successful one was in 2009 for otters in Portugal ( 1 Year later we did the same with otters living along the Irish coast. The smallest GPS trackers we made was for sousliks weighing 19 grams including GPS, GSM, accelerometer, flash memory, solar cells and a nano SIM card connector. The large ones were for giraffe (GPS GSM) and manatee (GPS Iridium). For the wildlife trackers we are now building a new website. See for a preview here: As a spin off we have developed a very small cattracker, called cattracer, based on GSM and LoRa (see For the LoRa version we will start a crowdfunding campaign in the beginning of next year. A small GPS tracker for a hedgehog is a challenge. We would really like to think with you about this! We have already delivered a GPS tracker for another spiny mammal: a porcupine. Best wishes Addy


@3dotter just for my curiosity, how do you deal with the duty cycle limitation (LoRa) for the cat tracker?

(Addy de Jongh) #23

We have a deep sleep wake up cycle. During deep sleep only the mcu's clock is running using almost no power. Sleep wake up cycles can be set with a scheduler on the server.


@3dotter Sorry, I guess my question isn't clear enough. I mean the transmission duty cycle of 1% which is enforced by the regulator. So, you only allowed to transmit certain number of packets every hour.

(Addy de Jongh) #25

The default settings are 4 GPS fixes/hour + accelerometer data frame, saving those locally and 1 data transmission of those/hour. Must fit like this. In Alarm mode when cat is lost as often as is allowed.

Later on we hope that geolocation by TDOA / RSSI in KPN / TTN LoRa network is good enough to omit the GPS receiver.

See here: from which it appears that: "Aka LoRa PHY and LoRaWAN MAC ... ... ons_v1.pdf

If you read between the lines, Page 5 nicely describes the advantage of LoRa vs. SigFox ...

SigFox uses the 1% duty cycle limitation on all channels. This limitation
boils down to the maximum of 140 frames of 12 bytes per device per day
(in Europe).

For LoRa, the 869.4 to 869.65 band allows for 10% duty cycling, which means 10x more air time just in this band.

In the typical gateway scenario with one channel in the 10% band, 3
channels in 1% band and 2 channels in 0.1%, there is 13.2x more air time
available for LoRa than for SixFox!"


Hi Addy, love the website, and love the idea of tracking otters too! That must have been a lot of hard wet work, but a lot of fun too :smile:

Good luck with the catracer kickstarter next year. If you fancy getting involved in hedgehog tracking, the link to the challenge is


This man was instrumental to the reintroduction of otters in the Netherlands!

(Gary Mortimer) #28

Down here in South Africa there are more than 10 otters living in the river that passes my house :wink:

I am interested in trackers for (this is going to sound horrid) disabled children at a local school. They already have GSM trackers. Lowering the cost and making it more robust, when the GSM goes down is my aim.


Doesn't sound horrid at all! Tracking kids seems very sensible. Not just for schools, but also for parents with kids that run away all the time (so almost all :smile: ), e.g. in shopping malls, amusements parks, etc.

For Trackey, we plan to into dive this use case after the pet tracker. Main difference we could think of between pets and children is that you also need to track them inside buildings. Also, you can't make them wear collars :wink:

@GaryMortimer, I'm curious to know how the GSM trackers are attached to the kids? As wearables? Any limitations there? What kind of disability school is it? Do you only want to track around the school or in a wider neighboorhood?

(Gary Mortimer) #30

Hi Arjan, they are wearables and its just two youngsters. They are allowed to interact fully with the other children at playtime and as such can disappear fast! The school is set in countryside so the potential to head into the hills is real! Geofencing would be great and I had completely forgotten about the ability to track indoors. That would be top notch. A very dear friend is the teacher and I have been there helping look for one of them in particular who enjoys vanishing frequently more than once. He's never far more frequent updates than the current product will also help.

(Addy de Jongh) #31

Hi Mark, I was away. Thanks for the compliment. How could I help you? Very interesting to be involved in hedge hog tracking :smile: Best wishes, Addy

(Addy de Jongh) #32

Hi Gary, Where in SA this is? Do you have photos of "your" otters? Which GSM trackers you use?

We have very small GPS GSM trackers (including indoor location) with a web and mapping interface. Different settings can be changed online like tracking frequency and geofencing. There is also a tracking app.

Best wishes,


there are many, many 'tracker projects popping up at the moment :sunglasses:


Can we please restrict these kind of discussions to Lora based devices. That is why we read and search this forum.

(Addy de Jongh) #35

You are right! Sorry :innocent:


Addy, this was not meant as response to you, but as response BorroZ'last post.


I do appreciate that your intention is to help others. My answer was from the perception of readers looking for Lora devices.
W.r.t. real time tracking JamesC has argues here the situation may not be that slow (depending on distance to a gateway). But maybe still too slow if you want to chase a stolen bike or run away pet.


Interesting discussion!
I think it is very good to set expectations straight and I agree that lora might not yet be useable for "chasing" using realtime tracking.
Tracking runaway pets may not require chasing though. Getting locations at 2 minute intervals will give you a general location and a direction in case the pet is moving. That should be sufficient for finding it again.

I wonder whether Geofencing would work. The delay may be just too long.


Hello everyone. I am planing to use TDoA or maybe RSSI with LoRa without GPS module on nodes. Does anyone know about if someone has already been working on it? Or a mature product using them has shown up?


Hello Wei,
Unless specifically used for pet tracking, a better topic to ask would be I think!