But I have a hard time generating good ideas. Any thoughts?
UPDATE: I miss remembered, we used the high impedance electrometer to buffer the input of a National Instruments interface board so we could record the voltage build up across the storage capacitors, if you use a normal voltmeter the caps just discarge into the voltmeter and the charge never builds up enough to allow the micro controller to turn on, run the code it needs to and then go back to sleep. You land up with some really nice sawtooth wave forms with this method and, as the acceleration on the vibrational energy harvester increases, the frequency of the sawtooth changes proportionally up to a point where the system is transmitting all the time.
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!
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 haven't added solar, as these are inside, near power, but have some solar panels and hardware waiting for me to deploy out in the field (literally). so far, it's been my lack of good waterproof enclosures that has slowed me down. I wonder if there'd be a good opportunity for someone in that space.
One of my favorite companies to work with in this area is Polycase.