ThinBot work in progress -- pump calibration and circulation chiller test

This morning I took the time to measure the flow delivered by each of the 8 peristaltic pumps and adjusted the software to take the differences into account (I have a way to adjust the values via a setup screen, but I might was well start with a table adjusted for reality). The pumps all work, and deliver between 66 and 88ml/min. They all also self-prime properly. Big sigh of relief.

The final mechanism to test on ThinBot was the circulation chiller system. Rather than deal with delivering ice and/or shaking/stirring, I'm chilling all the ingredients via chilled water circulation (an idea I happily admit stealing from the iDrink 'bot at last year's BarBot).

From a thermal reservoir (ice chest) of ice and water on the floor, the design calls for a fountain pump to fill the chiller/nozzle assembly, which will then drain into the upper bottle tank, which will drain in turn into the lower bottle tank, which then drains back into the reservoir. This will cool the spirits while adding visual interest as a table fountain. In theory, any way.

Satisfied that ThinBot could actually deliver cocktails, I moved the whole thing outside to test the circulation. If anything went horribly awry (or the aquarium sealant failed) I wanted it to happen someplace where it wouldn't cause damage.

Here's video of the first test:

Good news: it worked (after adjusting the length of the chiller/nozzle tank drain line slightly), and the fountain pump is sized perfectly (it's rated to lift a column of water 4 feet, which is perfect when ThinBot is on a standard-height table). Bad news -- the stream draining from the upper bottle tank to the lower tank splashed enough to spatter the table significantly.

On to try two -- at bovil's suggestion, I suspended a length of ball chain through the upper tank drain to just above the water height in the lower tank. It worked beautifully, quieting the splashing but still delivering the falling water sound.

In the home stretch now!

ThinBot Progress: To cap it all off -- Add a dome!

We observed last year that it was important to elevate one's power supply above the wet components of a barbot, lest leaks or condensation find their way into the wiring (one bot was offline for a while until its power supply could be replaced).

I'd already mounted my power supply and control relays on a shelf above all the other components of ThinBot, but wanted a little more protection from spilled drinks. Besides, a dome would just sort of finish the look.

After a bit of shopping (we considerd the outer bowl from a salad spinner, and another from a microwave popcorn popper, but they were both translucent rather than transparent) I found a polycarbonate serving bowl that I could repurpose as a dome:

( Photos under the cut )

I then reassembled everything so bovil could use a better camera for a final shot of the assembled ThinBot; I'll put that in a separate post.

ThinBot: Completed assembly!

We used Andy's camera to shoot some better photos than I could get with my iPhone.

Presenting (sans fluids): ThinBot!

( photos under the cut )