I was looking into making my own automated bar as a fun project to work on. I just had some questions about feasibility and different ways to approach it.
My idea was to use a Peristaltic pump to move the liquids around. This would allow me to accurately measure the amount of fluids that are dispensed. The problem is that they are expensive, so I would like to minimize the amount of pumps that would be needed. I was thinking of using 2 pumps, one for alcoholic beverages, and the other for non-alcoholic beverages, and using solenoid valves to select which bottle the pump draws from. My problem is finding a way to get the solenoids to flow into one output so I can feed that into the pump.
I am assuming that you can pump carbonated beverages through piping without it losing its carbonation. I was just mulling this over, and haven't put any money down. It seemed like it would be something neat to do, as well as something that I can expand to include more functionality. Thank you for any input.
Wnt2bsleepin:
I was looking into making my own automated bar as a fun project to work on. I just had some questions about feasibility and different ways to approach it.
My idea was to use a Peristaltic pump to move the liquids around. This would allow me to accurately measure the amount of fluids that are dispensed. The problem is that they are expensive, so I would like to minimize the amount of pumps that would be needed. I was thinking of using 2 pumps, one for alcoholic beverages, and the other for non-alcoholic beverages, and using solenoid valves to select which bottle the pump draws from. My problem is finding a way to get the solenoids to flow into one output so I can feed that into the pump.
I am assuming that you can pump carbonated beverages through piping without it losing its carbonation. I was just mulling this over, and haven't put any money down. It seemed like it would be something neat to do, as well as something that I can expand to include more functionality. Thank you for any input.
I think you're going to have some very messy alcoholic drinks. Imagine passing advocaat, creme de menthe and whisky through the same pump, one after another!!!
Why not use a similar method to how pubs measure and serve drinks? Use solenoid operated optics. Move the glass under the required optic before activating it. That also solves the measurement problem. In pubs, carbonated drinks and draught beers are dispensed (under pressure) from a 'trigger' or tap. You could replace the trigger/tap with a solenoid valve. If all your glasses are of a standard capacity, you only need to time how long it takes to dispense a 'glassfull', assuming that the pressure is kept constant.
Yeah, using 1 tube to dispense multiple fluids sounds like a prescription for
gucky-tasting stuff. Maybe could squirt through some clean, clear water at the
end to flush the tubing. That 10% you're watering down the drinks will also be
90% of your profit margin, ;-).
If you want to know about carbonation, ask the guys at Burger King where the
injection point is for the CO2 in their soda pop.
Flushing the lines would work, but I guess dealing with the water would cause issues. I would need to prevent it from being mixed in with the other drinks. So, it looks like the option is to pressurize the bottle containing the alcohol, and letting a solenoid control the flow. I can use a optical sensor to measure the amount of liquid in the glass, but some of them are crystalized and I don't know if it will work for them.
The other option is to use one pump per drink. At ~70 dollars each, this can get expensive very quickly.
Food grade pumps are likely to be expensive, and difficult to keep hygienically clean. I would have thought that solenoid operated valves would be easier to use but would still need cleaning. One option it to use displacement to dispense the fluid - put some sort of liquid-filled bladder in the bottle and pump the liquid in to displace the bottle's content via an overflow. The pipework would still need cleaning, but it wouldn't have any moving parts to clean.
I would have thought that measuring by weight would be easier than doing it by volume, for small volumes.
Wnt2bsleepin:
Flushing the lines would work, but I guess dealing with the water would cause issues. I would need to prevent it from being mixed in with the other drinks. So, it looks like the option is to pressurize the bottle containing the alcohol, and letting a solenoid control the flow.
Mount your optics and bottles on a carousel. Turn the carousel until the required bottle is over the glass. Lift the glass to open the optic. Wait until the optic is empty. Lower the glass. Serve the drink.
Pros:
Two stepper motors, no tubing or pumps to clean, accurately measured volume, will work with 'crystalised' glasses, all very simple.
Cons:
All your glasses would have to be of similar height or you'll need to test when each glass has been lifted enough to operate the optic, but not enough to smash it.
Wnt2bsleepin:
The other option is to use one pump per drink. At ~70 dollars each, this can get expensive very quickly.
Why not make 'm by yourself ?
The principle of a peristaltic pump is pretty simple. These (sorry in dutch) diy-pumps hardly cost anything, they are probably far too slow/flimsy to use though, but perhaps you've already got most of the stuff laying around to design/create sturdier versions. Just google "peristaltic pump diy" to get some ideas. I would spend money on special tubing since it will have to endure a lot, but why spend much more as that ?
Need anyone to adjust/test the end-results by the way ?
I am thinking that the gravity fed system will be the easiest to make. Although, it can be a problem to store it as I would need to put the tap at the bottom and build up from there.
I could also look into building my own pump. Having one that can accurately keep track of the amount of liquid that is dispensed would be ideal, but with that measuring cup idea, I could work around that.
Although, I did find these and they are cheaper. They are not food grade, but swapping out the tubing should make them food grade right?
I've been thinking about a similar project myself and looked at pumps to begin with.
It looks like the Ulka EP5 is the most commonly used pump in vending machines and coffee machines but I found it way too expensive.
I also wondered what would happen to the pumps after pumping liquer and coke and all kinds of gooey liquids through them.
Then I decided to go with a carousel solution and got myself some Beaumont Optics just like the one Henry recommended but that's as far as I've come. Need to figure out a way to lift the carousel steadily when I have time.
I agree, I know that this has been done before but the journey is the fun part, not the destination.
Looks like the optics are the way to go. I will probably use some sort of carousel or track system to dispense the drinks. That way I don't really have to worry about tubing as much as possible.
In hindsight, using standard optics sounds like a very smart move for stuff that will be dispensed in those standard measures. Does that cover everything that you need to dispense?
It should cover everything. I will probably use an Optic to measure some fluids and it should work well with those. I am just torn on what kind of layout I should do.
If I go with a gravity fed system, the design will be simpler with little to no pumps, but it will have to have a rotating carousel or some other way to align the cup with the drinks. It will also have to be built up vertically and may be complicated to assemble.
The pump system would look nice, I could put it into a cabinet or something. It would need pumps though, and the cheapest I could find them at was 23 dollars. Then it's a matter of dispensing them since I don't want to use one pipe for everything, I have to somehow get multiple pipes into one tap so they can be dispensed.
Ben Krasnow is building a carousel-based food dispenser, if you look at his YouTube channel you might get some inspiration for the mechanical design. Do you know how many different bottles you will need to support - is it a small enough number that you could just arrange them in a circle around the glass all pointing inwards so they all pour into the same glass?
I would suggest using these valves (www.thingiverse.com/thing:12311) if you have access to a laser cutter it will only cost you about $6 using servos from ebay and they are food safe and fairly easy to clean. Ive been experimenting with different ways to dispense liquor for the past couple years, whether it be by compressed air & solenoids, to windshield washer pumps, to Peristaltic using the bar I built in my basement and I will say that you will be spending anywhere from $150+ no matter what method you use. Peristaltic pumps are clean but too slow (about 30s to pour a shot), windshield washer pumps break down from the sugar in drinks and always need to be primed, and compressed air + solenoids works wonders but is hard to gauge the viscosity to pour the perfect shot.
I find that at a head height of 45 in. I use about 10 psi for most liquors and I seem to get pretty close to 29mL (1 oz).
I don't have access to a laser cutter unfortunately. I am also thinking that I will go with the conveyor system and I will use a pump to dispense water and soda. It will both look good, and be easier to maintain and build. I will probably use solenoids to dispense a measured amount using the Optics when the glass is moved under the proper optic. I would assume that I can pour the drinks faster using this method than having to pump it up through piping.
I do not know how I would begin to build the conveyor system. I don't even know if Conveyor is the right word since it will be a moving platform on rails. I will either use photodiodes or perhaps a servo to determine where the platform is at a given time.
Finding optics in the US is somewhat hard. I ordered one form Amazon, but it's not going to come in until June =(
Wnt2bsleepin:
I do not know how I would begin to build the conveyor system. I don't even know if Conveyor is the right word since it will be a moving platform on rails. I will either use photodiodes or perhaps a servo to determine where the platform is at a given time.
Use a horizontal screwed rod. Fix a nut to the underside of your platform. Turn the rod with a stepper motor. The platform will travel (on its guides) along the rod. Where it stops can be determined by the number of steps you tell the stepper motor to take. No detection, apart from a 'home' position microswitch, needed.
You only need to raise the glass enough to push the bars of the optic up to release the drink. I would use the equivalent of a scissors jack on each side of the platform, to raise the glass evenly and keep it level. Again, I suggest a stepper motor for this.
I looked into stepper motors more, and they do seem like the way to go.
Where would I buy the threaded rods and all the other misc parts? I was looking for some sort of all-in-one store that would sell them. I plan on buying the stepper motor and other wiring stuff from Sparkfun and Radioshack for other stuff I may need.
Wnt2bsleepin:
I looked into stepper motors more, and they do seem like the way to go.
Where would I buy the threaded rods and all the other misc parts?
As we have no idea where in the world you are, how would anyone be able to advise you?
I can tell you where you could probably get those parts in the UK, but that may be of no use to you.
