Im trying to construct a system for my reptile that once a day pumps old water out of the water bowl if there's any left in it and then refills it with fresh water. Does anyone have any suggestion how to achieve this?
Step 1. Arduino controls relay that turns on wet/dry shop vac at designated time. Water is rapidly sucked out of bowl.
Step 2. Container mounted next over sink is allowed to fill to capacity via slow drip, any excess goes in the sink. At designated time, servo unwinds lower container which pours water down a tube to the water bowl, then reverses container back into position to begin refilling.
Perhaps Step 1 might work better also for emptying the bowl 8)
Yes, but where's the challenge in that?
Can have a 2 servo approach for emptying the bowl.
Spring loaded bowl on a hinge is pulled down into place with servo 1, then servo 2 slides a pin in place to secure, after which servo 1 can be unwound.
At the designated time, servo 1 pulls the pin, bowl is popped up to aggressively empty the water, then pulled back into place with servo 1 & repinned with servo 2.
Servo 3 then unwinds to let water container tip over to refill the bowl.
Now somehow we need a steel ball rolling down a track to release the mousetrap to start the process at the designated time ...
Step 1. Arduino controls relay that turns on wet/dry shop vac at designated time. Water is rapidly sucked out of bowl.
From the reptile's perspective, that gives a whole new meaning to the phrase "water hazard".
Yeah, maybe a little air raid warning first - he didn't say how big the reptile was.
I'd go with a cheap aquarium/pond pump to pull the water out. Run it for X seconds, X being a second longer than you've tested it to take to get the full bowl empty.
Then run a similar pump in your reservoir of clean water for Y seconds, Y being a second or two less than you've timed it to take to fill the bowl completely.
Use a narrow hose for the fill pump so it takes say 10 seconds to fill the bowl to the brim, that gives you plenty of leeway between filling and overflowing.
Alternatively you could use a float, or a resistive sensor, a pressure sensor, or a capacitance-change sensor to tell when the bowl is full. Or both that and a timer, for backup.
To empty the boel, how about makign a hole int eh bottom of it, attatch a little plastic tubeing and use a mechanical valve. Open it up, water drains out by gravity. You can collect the water in a tank.
For filling, have a tank above the bowl somewhere, plastic tubing and another mechanical valve.
Gravity sucks!
The only problem I see with tubes & valves & such is them getting clogged with reptile debris, little sticks, whatever is in the terrarium (?) that is loose and could fall in. Lifting a side of the bowl & dumping it alleviates that.
I suppose the water still has to drain into something tho - that could be a screen/grate over a funnel with a wider tube that would be less likely to become blocked.
Not a reptile keeper myself, not claiming any experience here.
Maybe a very powerfull laser that can heat the water and boil it off...
Or it could make barbeque'd reptile, that could be tasty too!
skyjumper:
To empty the boel, how about makign a hole int eh bottom of it, attatch a little plastic tubeing and use a mechanical valve. Open it up, water drains out by gravity. You can collect the water in a tank.For filling, have a tank above the bowl somewhere, plastic tubing and another mechanical valve.
Gravity sucks!
I second this system. One addition could be to have a third valve on a faucet/supply to refill the clean water tank after each drain cycle or a certain number of drain cycles. Or bypass the fill tank altogether and use the 2nd valve to lead directly from a faucet to the bowl. As a matter of fact with the right tubing you might also be able to bypass the drain tank altogether and have it drain directly to a sink/drain/outside. All you need for that is tubing and valves (and the Arduino of course).
Recommend using a filter to keep those tubes clear. Would be the only upkeep for the system.
KE7GKP:
Recommend using a filter to keep those tubes clear.
Using a valve for the drain could prove very problematic because any kind of foreign debris could prevent the valve from closing, and that would prevent the bowl from holding water. And putting a filter before the drain valve means that you are retaining whatever foreign debris in the bowl along with the water. That just doesn't seem very desirable to me. That is why I suggested flushing the bowl by refilling with a bowl-full of water and displacing whatever leftover contents (water + debris).
Very good point. But that flushwater, debris and all, has to go someplace..
KE7GKP:
But that flushwater, debris and all, has to go someplace..
Right. Which is why I asked about the drain in my first response. But tallrot has never returned to this discussion, so we may be all just wasting our time here.
Its not waste of time. Its fun talking about cooking reptiles with giant laser beams!
You could filter it after it leaves the bowl (via a hole in the bottom) and before it gets to the pump.
A mesh filter would keep the pump happy, and is easy to make.
It doesn't make that much of a difference to me whether he comes back or not, I like playing with ideas in my head even if they have no chance of being used.