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Comment by beachy | Hacker News Reader

I am working on a lora/arduino mesh network for reporting back the state of a large number of traps for invasive predators (mustelids, possums, rats).

The traps are spread around the countryside in dense bush/jungle.

When one goes off, someone needs to tramp in and clear and reset it. Currently, there is no monitoring of any kind, so checking traps is extremely labour intensive.

The trickiest aspect of this project is that each node needs to spend virtually all of its time asleep to minimise battery drain, yet for two nodes in the mesh to communicate, they both need to be awake at the same time. Drifting clocks etc.

The easiest aspect is that the acceptable data rate is 1 bit every 8 hours or so!

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What a cool and useful sounding project! Does LORA handle any of the meshing aspect, or do you have to manage that at the application level? Also what kind of node to node range are you getting from the radios, and when the users install them, how do they know they'll be within range of the next node?

Yeah, it is some fun, wish I had more free time to devote to it.

LORA doesn't handle any of the mesh behaviour, I'm doing all of that using LORA just at the send and receive level. The devices I am using are moteinos - a cool arduino lora mashup https://lowpowerlab.com/guide/moteino/.

I see various ranges from LORA, the environment is steep valleys and dense bush which severely dials back the range, sometimes down to a few hundred meters or even less. At this stage I haven't played around with optimising the LORA settings, but there are bound to be some wins there since the required data rate is so low.

Good question about installs, my current plan is that before setting out, the user places that part of the network where they are heading into constant beacon mode. The node can then be installed, knowing there's another node within reach.

In practice this should be fine anyway, as the recommended placement for traps for e.g. stoats is every 100 meters or so, so usually there will be other traps within range.

I'm totally ignorant about radio hardware, but I'm curious, why not use a chip with wake-on-radio?

Good idea, except that wake-on-radio requires the radio to be powered on all the time. Whereas I need to sleep everything except the arduino watchdog.

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