Arduino garden fountain auto-filling system

Communities Science, Engineering, & Security
1

We have a simple little garden fountain kind of like this

Down here in Alabama ('Murica y'all) it gets very toasty outside in the summer. We all know what happens when water gets hot...It vaporizes! And we all know what happens when too much water vaporizes in a fountain...it burns the pump up! (definitely don't know this from experience)

The way the fountain is put together, it's pretty easy to take the middle "cylinder" and the second tier off (making it look like a birdbath for all intents and purposes) and in the middle of that is where the pump is. There's quite a bit of extra space in there, certainly enough to run small tubing (like aquarium tubing or something, not a garden hose) and be able to discreetly fill up the fountain without having to lug a water pitcher out there. There's also plenty of space to put electronics and whatever underneath the fountain, because the bottom is all hollow. There's already an electrical outlet there to power the pump, so I was wondering how hard it would be to make some kind of Arduino thing that would detect when the water is below a certain level, and then flip a valve to fill up the fountain. It doesn't need to actually pump water, there's a garden hose spigot nearby that we could use for this, I just need the arduino to control a valve (like a sprinkler system valve maybe?)

I was thinking of using a Raspberry Pi instead of an Arduino, because it would be cool to be able to automate the fountain and because that means I can hook it up to a network and maybe also have it put algae remover in there during the really nasty times...but I dunno, is there a way to hook up an arduino to ethernet and have it do basic stuff? I don't need to run a web server or anything, but if it can send data to some sort of logging mechanism that'd be great.

And of course there's the physical structure of it all. I would have to drill a small hole in the center of the fountain to run the tubing into it, and I'm not sure how I'd do that. I guess use a hole almost the size of the tubing, and put some caulk around it?

And the valve....what would be a valve that is off by default (i dont want it to start overflowing because the power went out or the arduino lost it's mind) that I can easily hook to some small tubing? I would have to take in water from a garden hose, but I could probably use a seperate adapter to get it down to a smaller tubing size, and obviously I would keep the pressure pretty low. Any ideas?

And lastly the actual water detector. I know you can detect a water level using 2 wires and when the water gets over them the circuit completes, but I don't know how well that would work for this. Is there a way I could have it detect how full it is in percent? And if the classic "2 wires" idea is the best way to do this, is it going to make touching the water dangerous? I would think if I used a very small amount of electricity it wouldn't matter, but I don't want to accidentally fry some bird that lands in the water on a hot day...

Help! I really want to do something like this but I'm clueless :P

2

You will need a float switch to activate the controller.

This is one from work. It is a bit over kill for you but something like it.

image.jpg2448x3264 1.45 MB

Caulk would work but some rubber gasket material would be better.

You could use a ph sensor for when to add some chemical. You will have to research that since I am not sure on the numbers for a bird bath.

For the valve the term you are looking for is "fail shut" but a small pump and swing check valve would most likely work if you can't find a motor operated valve. A swing check has a weighted gate that causes it to shut when there is no flow and only allows flow in one direction.

3

If you could take some pictures an get measurements I could help you a little better.

4

So if float swith is closed the arguing starts you fill live until the switch opens again wait 2 minutes for the ph to equalize then check ph if it is out of spec the chemical pump starts for how ever long to get get a treatment and then stop the pump.

Then the loop starts over.

Hell if you want to get fancy put a float swith in the chemical tank and have it send you an AMS when it needs refilling.

5

I'm replying to both of y'alls posts here because I'm lazy :P

For the flow switch...like this?

http://www.grainger.com/product/DAYTON-Float-Safety-Switch-2HXZ4?s_pp=false&picUrl=//static.grainger.com/rp/s/is/image/Grainger/2P874_AS01?$smthumb$

If that's right, is that going to allow me to tell (roughly, in percent) how full the fountain is? It's not a necessity, but if I could log that I could have a thing on my web server generate a graph of it in real time, and that would be kind of cool.

Also, I think I've settled on an Arduino because of the simplicity, as long as I can control it over a network for basic stuff. (Can someone confirm this please? I'm a nood with Arduino) and since it has way more IO pins than I would need for this, I was wondering how hard it would be to wire up some RGB LEDs to go in the fountain. I know where I can physically put them, as long as submersible flexible LED strips exist...

And as far as the chemical, how would you recommend pumping the chemical? Obviously it's not coming from a garden hose, so I'm not exactly sure how to go about storing/pumping that. I have the space to store the chemical's bottle itself underneath the fountain, but I'm not sure how I would get the chemical up to the top of the fountain (I know I use a pump but like what kind and where do I get it :P)

Thanks for all your help everyone!