Location Tracker & Data Logger: LoRa (Meshtastic?), WiFi, GPS...  - Page 1
Forum section: electronics / projects

author: MathematicalJ
author_rank: Contributor
timestamp: April 12, 2024, 04:44:20 pm
content: Could you guys tell me which projects I should look into for this stuff? I'm finding it really time consuming to sift the wheat from the chaff. I know the major ingredients exist in some form or another, and there might even be a complete project that already puts it all together to do what I want. Here's what I'd like hardware-wise:1. GPS logging2. WiFi3. LoRa (Meshtastic?) for when WiFi is unavailableI can find lots of devices with these hardware requirements. But could you direct me to the software I should learn about? The idea is that I DON'T want anything requiring a subscription or SIM card. I am sure there are open databases of publicly available WiFi networks. It would be great to have a microcontroller library that can query such a database for local networks (e.g. results within 3 miles of current location), cache the results, and then automatically connect to whatever network is within range. For example, the device might use the SSID and pass phrase for a local coffee shop, or automatically accept the WiFi access terms required to connect to unsecured McDonald's WiFi. I don't know if WiGLE does what I want or not... in any case, surely such a database exists, and I would think that the microcontroller code to take advantage of it has already been written, too. What should I be searching for?I want to use it for semi-real time monitoring and data logging potentially for two separate use cases:1. vehicle monitoring, data logging, and location tracking, and2. keeping tabs of a special needs family member as they walk the dog through our local neighborhood. The neighborhood is generally safe, but the family member is vulnerable, and everyone would have a lot more piece of mind giving them the freedom to be out with Fido by themselves if we could detect if they have stopped at some strange house or something like that.It would send small amounts of data every minute or so when internet connectivity is available. Off device, say, on a desktop computer, could be a monitoring script that could send a notification if it doesn't get an update after some amount of time, maybe 10 minutes or so. I can write that code pretty easily, but there are probably frameworks already set up for this kind of thing.Whether my local area has the network coverage and/or unobstructed range for LoRa to do what I want is an open question and part of the fun of doing the project, of course. One possibility is to have really simple LoRa-WiFi internet bridges in strategic locations using cheap hardware. The bandwidth, data rate, and power requirements are so low that I would think such a bridge could be made for just a handful of dollars. I've seen commercial devices that do this, but they strike me as way overkill and cost about 10x more than I'm willing to spend.

author: uer166
author_rank: Super Contributor
timestamp: April 12, 2024, 11:09:01 pm
content: Quote from: MathematicalJ on April 12, 2024, 04:44:20 pmReality check: a basic LoRa transceiver alone is >$10. I just designed a LoRa+GPS device, CBOM is $200 not incl. labor to build.For local neighborhood, I would recommend putting a LoRa transceiver at your house, and just doing point to point comms to the tracked device (in an FCC compliant way of course, with frequency hopping etc). As a reference point, I am able to get 2-3 miles range between houses in a big downtown/metro area. Meshtastic only works if you have, well, a mesh of many devices, it's a bad fit for both of your use cases. If you can install your LoRa device high up in a tree or a mast, there's no need.For a vehicle tracker, it's much more difficult, and I'd recommend trying Helium network or LoraWAN, though in both cases there are serious constraints on bandwidth/duty, so it won't really be "semi-real-time", more like one ping an hour or something.

author: SiliconWizard
author_rank: Super Contributor
timestamp: April 12, 2024, 11:33:44 pm
content: Yeah, GPS+Wifi is no big deal (but there are already tons of such devices, so not sure it would be worth it designing yet another one.)Adding LoRa will indeed add significant cost and complexity.Note that if you're interested in Meshtastic, their "reference" designs are based on ESP32 dev boards (and a couple others) and have GPS. No Wifi though, but BT, with a mobile app that can communicate with the modules, so that would fit your needs. Buying one of these Meshtastic ready-made boards may be all you need here, unless you want to design a product that you'll sell.The only thing that may not be done by default in the Meshtastic firmware is GPS data logging (I think it can just send GPS coordinates periodically to other nodes), but I bet this could be added without too many difficulties. So I'd say this may be your best bet here, or at least something to start working on, until your project matures and your knowledge of LoRa too, and after that, maybe you can consider developing your own board.Just my 2 cents.

author: Kim Christensen
author_rank: Super Contributor
timestamp: April 12, 2024, 11:41:26 pm
content: I've often thought of setting up a Helium hotspot to earn credits and then using their network which is quite extensive. The downer is you have to buy their overpriced miner hardware.