Van-O-Meter
I've been thinking about monitoring the environment in my vehicle, things like temperature, humidity, CO, etc. I can think of a number of applications that this could be useful for. Here are a few:
- Monitoring moisture levels to prevent mold. If you have humidity data, you could catch problems early and verify that any mitigations are working.
- Monitoring temperature levels. Maybe you need to leave the dog in for a few minutes and want to be sure the temperature is safe. Maybe you want to avoid food spoilage from elevated temperatures, etc. You could also quantitatively test heating and cooling solutions.
- Monitoring for CO to warn of danger.
It was just kind of an idea, but then I came across the Thunderboard which has basically everything required to do this out of the box, is all open source, and is only $36.
I've used Silicon Labs products in the past and have been very impressed. They are very nice low power devices with a nice development environment. If you wanted to do remote monitoring, you would need to keep a cell phone paired with the board in the vehicle so that it could stream data to the internet. So in addition to the board, an extra cell radio with data would be required. If I get some disposable money, I'll probably pursue this.
Is it necessary? No. Would it fun to mess around with? Absolutely. Can you think of any applications you would use this for?
For some of us, frost is also an issue. I always have fresh water in the water tanks, I have water taps, septic tank, open seacocks and there is even sea water in the secondary cooling circuit. I keep the frost out through land power and/or the diesel heater, if something should break white I'm out, the result can be a disaster.
Next, battery level needs monitoring all year around. If it falls below 12.3V I should check up and charge. If it falls below 12V it's quite bad. I once had guests, they left a DC/AC inverter on, the water tank was empty and the water pump was going and going and going, and then they found it prudent to disconnect land power when leaving. When I got back, the voltage was 10.5V, and the capacity of the battery bank is really bad after that incident.
Burglar alarm and fire alarm should obviously be included.
Water detection, water can get into the wrong places both due to rain water leakages and sea water leakages. Particularly the latter is of outmost importance to learn early.
GPS position. Nice in case of theft, or for anchor alarms.
I have a raspi that monitors temperature in the cabin and engine room plus humidity and it also takes pictures with a small camera, but I never got time to tinker more with it. It's of no use as long as I don't get alarms.
I have some closed source Raymarine navigation systems that also includes quite some sensors, including radar and depth meadurement. It sucks big time, there is quite much cool one could do with the data.
Thanks for the input. Ya, monitoring for freezing temperatures is another good application. Do you have solar panels and a charge controller for your batteries? Some charge controllers can disconnect loads from the battery when the voltage drops too low to prevent battery damage. GPS position could be monitored via the cell phone portion. That's too bad you can't use the Raymarine data.
I have an overdimensioned Morningstar regulator, haven't checked out if it has such functionality. Still, not all circuits are suitable. The diesel heater should never be disconnected while running (and it will turn itself off if the voltage is too low). Some of the things - for instance the bilge pumps - are supposed to "run to destruction", if the options are between everything sinking and the battery bank getting drained beyond rescue, then ... you get the gist. Anchor winch and bow propeller consumes too much power to run through any delicate electronics, and is also regarded as emergency equipment that shouldn't still work as good as possible, even if the voltage drops a lot - which it will, when pulling lots of amps from the batteries. It's important that the navigation system keeps working even if the voltage should drop.