I am new to Arduino and want to create an automatic petrol bushfire pump starter/controller.
The pump uses a Honda GX 200 with 12v electric start.
We currently have rigged the fire pump to a wired remote start from inside the house, using long wire leads and a car door actuator for the choke.
We desperately want to create an auto start for our fire pump in the event of bushfire when we either/or
are home and want to escape a bushfire but leave the pump cycle to turn on for 5 mins, off for 5 mins, to conserve water while we escape but save the house
auto start if fire arrives (temp or smoke sensor?)
remote start by mobile network
Specs
Aussie fire pump
Petrol Honda engine 5.5 hp GX petrol engine
Ideally it would
turn choke on (using car door actuator we installed)
turn pump on
turn choke off
turn pump off after 5 mins
turn pump on again after 5 mins (no choke required for 2nd start)
Sounds like you already have a lot of the stuff you need, some relays across your current switches will sort out most of the hardware (as long as the wires are protected).
The hard part will be detecting the presence of a fire I guess, would detecting ambient temp be good enough and be in time?
I guess the pump is driving sprinklers on the roof? It would be nice to have that running before the fire hits I would think.
You may need to get information on the dynamics of a fire front, speeds, temp profiles etc.
Sprinklers on the roof would be the best,
Idea: collect the water from the gutter filter it and reuse it.
Fire detection is a problem as a spark can fly dozens of meters and fall on the roof.
The system should also be able to do testruns, once per month 5 minute or so, to see all things work. This includes checking the level of the battery used.
Well as I said all you really need to do is put two relays across your existing switches and have the Arduino control the relays. That part is simple, just buy a relay shield.
If you go to phone control then there are GSM shields around that will receive an SMS and send it to the Arduino.
As for the 12v, that simply needs a regulator or one of the many $3 switching powers supplies available on eBay.
Then you write some code.
I won't address the fire-detecting part because I think it's too hard without spending a lot of time on research, unless you go for a simple temp/smoke sensor as you say.
OK I will What about using optical/thermal techniques whereby you get an image from several thermal cameras and check for hot spots. I've never done anything remotely similar but I reckon the technology would be common these days and I know there's software for embedded systems that can be used to analyse images, just can't think of the name right now.
This could be tested as well with a fire in a drum or something simple.
Yeah, it only goes to 220 degrees but I suppose you can consider anything higher as a problem, you don't need to know the actual temp.
Trouble is where do you point the thing? You'd need about 50 of them I reckon. And will it detect a front 1km away?
The more I think about using thermal cameras the more I think that's the way to go, despite (or maybe because of) me not having any experience with them. Normally we don't recommend any form of image processing with an Arduino but in this case it's nowhere near real time and you are really just looking for a simple pattern with an algorithm like "5 yellow pixels in a row, it's time to go"
And there are new Arduinos coming out with plenty of grunt.
I have mate with a system for intruder alarms, he can monitor his shed in QLD from his bus which is currently in WA. I was out there the other day working on something for him and he could see me clearly and direct me in real time to the appropriate shelf when I was looking for some parts. If you used a powerful master board you could have a web server on it and control the entire thing from the web using any browser.
With some cameras (or one that can pan) pointing outwards and a couple more pointing at the house itself you should be able to detect any hot spots. This is an order of magnitude (or two) above what you are thinking about with a few temp sensors, but realistically I can't see a few sensors doing anything useful. Also with cameras you may be able to switch to non-thermal mode and view the property for security reasons like my mate does.
Anyway this may be too much for you as a beginner (I assume) so I won't be offended if you decide to put 3 sensors in and call it a day Certainly this should be done a small part at a time, you can always add stuff. So I'd work on getting the Arduino to control the pump, then maybe get it to read and act on an SMS. That will give you a nice remote manual system that's 1000% better than what you currently have. Then with more confidence and more research look into automating the system using cameras or whatever.
If the downpipes are blocked up (as they should be when in this situation) you may not actually need much water so a 10-20% duty cycle may be OK just to keep a film of water on the roofing material.
Also the absolute times will be important, ie 1 hour in 5 is 20% but not very useful, I'm thinking maybe 1 minute in 5 but ramping up to 100% when the fire gets closer as the water will evaporate faster as things get hotter.
Another thing that may need an expert to advise on.
publiclab.org docs on Melexis infrared temp sensor. You could probably just use one and rotate it like a beacon to sweep the area around the house. They have a 40 degree sensing angle. IIRC about $12 USD. From Publiclab's other docs on the sensor it seems it should be able to detect a fire at a decent distance.
For anyone still reading this. Use a check valve at the pump and keep the system pressurised. Use automatic sprinkler heads and a pressure switch on the pressurised line. This essentially uses the sprinklers as your sensors or detectors to activate the system. The pressure switch will detect the drop in pressure /broken sprinkler and initiate the arduino for pump start. Alternatively use a VESDA to initiate the system. This is how it has been done for eons in the fire protection industry and is proven.
wow, I hope he didn't suffer a fate for which he was worried......
my thoughts were to put up a water tower. stored energy by height.
today, we would suggest a ring of sensors, other peoples....
tie into what is happening a mile, 5 miles, etc away in all directions.
we have seen that to measure cold fronts to help anticipate the need for heat before the local temperature dropped.
interesting that we have seen a few 10+ year old threads pop up.
