I’ve got a few sensors I’d be keen on moving data wirelessly between.
The first is the Solar Hot Water system, which is where I wanted to start – wirelessly read some temperature sensors, and send them to the server for logging purposes, and set up a warning to turn on electric heating if need be (it’d be a relay if it could, but it can’t at the moment).
The original point was so we could gauge some idea of how much hot water was flowing out to the flat compared to the house, but then looking at the system since we’ve again emptied the flat, the solar hot water is easily serving our requirements – it’s obvious the source of waste was the flat. Still would be useful to have wireless information on.
Next, I have some thoughts on monitoring the moisture and temperature of the soil, and then have a pump trigger as appropriate, to find and keep them in the ideal growing range. Not enough time to put that together in a good way.
Wireless data is easily done with the Arduino microcontrollers and the NRF24L01 from Nordic, and another use which I have just started putting together is wireless data transmission – I’ll be hooking it up to the serial line in the car to get that data wirelessly transmitted whilst I get the protocol data. Store this, read it, and then it’s just a matter of sending that data out correctly, to get the same data in reply.
The difficulties are not in the circuit (though this can be somewhat not so simple to put together), it’s not in the code (that’s easy, even if you do forget to allow for some events), it’s in the enclosure – putting them together in a way that allows the board, battery, and additions in a neat manner is not so easy.
Creating a custom board with the microcontroller and wireless chip on it would be a better idea – with inputs and power planned in the design.