
Build your own drink mixing robot - ytham
http://yujiangtham.com/2014/05/25/build-your-very-own-drink-mixing-robot-part-1/
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hemancuso
I've always thought something like this would be a fun idea to build a
cocktail bar around. 80% of making a great cocktail is precisely measuring and
combining high quality ingredients. .

If you spent some time making a very attractive machine that was fun for
patrons to watch, mixed great drinks that were finished with a human touch, it
could be a really interesting draw. I imagine a place with a beautiful/badass
MIT-made drink-mixing machine would do quite well in Kendall square.

Create list of 8-10 interesting drinks that change weekly, that source from
perhaps a dozen different liquors/fresh juices. The machines selects one of 4
glasses that was already clean, could precisely measure/mix/shake the drink
leaving the bartender to garnish, present, squeeze fresh lemons into a
container. I think you could have a quality experience.

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conanbatt
Even better, you can make a recipe API, and given a set of ingredients and
some configuration, anyone can suggest a drink or pick one if available, so
every robot mix drinker makes the exact same cocktail in any bar.

Use case: I like my Old Fashioned strong with a slice of lemon instead of
orange. Make recipe, put online. Go to any bar with robot mixer: same Old
Fashioned everywhere!.

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kokey
I've always thought some kind of automated drink mixing system would be good
for busy inner city cocktail bars. You can still have a bar where people can
sit and watch someone mix drinks, but the rest of the venue can be tables with
table service. The orders from the tables are taken by a person and gets sent
to the kitchen where the drinks are made by machine. This will retain the
personal touch of people attending to tables personally, and allow them to
serve drinks often, promptly and consistently.

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chrissnell
I don't mean this in a disrespectful way, but what kinds of drinks are you
drinking and where are you drinking them? Yes, a robotic mixer might work in a
crappy bar for standard bar drinks like a Rum and Coke, Long Island Iced Tea,
etc., but anything beyond the standard pour-and-serve is probably best done by
the human touch, especially if you're charging big city prices for them.

That said, there are some places that do use quick mixers to mix up the
classics. Garduños, a huge Albuquerque, NM mexican restaurant (as seen in
Breaking Bad, season 5!) uses pre-mixed margarita mix from a keg and dispenses
it with a typical bartender's soda gun. They've realized that most people who
order "well" margaritas aren't that discerning and appreciate the consistency
that a factory-mixed 'rita delivers. Garduños serves them by the gallon and
the pre-mix saves them lots of bartender time when they're mixing their most
popular cocktail.

This would never fly in a nice bar, though. These days, most big city bars are
chasing the money and the money is in "craft cocktails". It's all about the
ingredients and the customized drinks that are tailored to the customer's
preferences. Bartenders are making a big show out of things like twisting a
slice of orange peel to release its oils. The presentation is hugely important
here and a robotic mixer just doesn't have the right vibe, in my opinion.

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drzaiusapelord
I'm not buying the "robots can't make drinks" argument.

Restaurant automation was big in the 1960s and 70s, but it eventually became a
flop. The technology mostly worked, but in the end, customers came more for
the "culture" of the restaurant or bar. That is, to chat up the waitress, have
a short conversation with the bartender, and most importantly, to not feel
lonely.

Part of the "big city prices" is the exclusivity that place delivers, not how
fine the process for making the current hot drink is.

Restaurants and bars aren't like most businesses. They don't just deliver
product. They deliver some sense of shared culture, some sense of exclusivity,
and some sense of 'here is where my kind of people belong.' That is also why
we mock chain restaurants, some of which deliver perfectly fine food, but are
seen as too 'cookie cutter' for the social experience we demand.

I say bring on the robots. I go to a lot of live music shows and waiting on
drinks takes far too long and heaven forbid I get the "too cool for you"
bartender and his weird douchbaggery on top of the drink I want. Maybe the
bartender role will go the way of the elevator operator or travel agent role.
Or higher end places will keep it and the rest will have a bartender sysadmin
position to make sure everything keeps running, fills up supply, orders
everything, calls service, etc.

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timo614
They'll probably always need some human around for liability reasons. That is
unless the robot bartender is going to add some sort of breathalyzer component
to see if people have had too much.

Also unless it's a club it likely would need to scan the person's ID and
confirm whether or not the person was who the ID mentioned adding some
complexity to the robot that otherwise wouldn't be required for just serving
drinks.

The sysadmin person you mentioned could definitely take on that liability role
in addition to anything else he needs to do to support the robot.

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fit2rule
Nice! Still got a ways to catch up with these guys though:

[http://www.roboexotica.org/](http://www.roboexotica.org/)

Includes regularly-scheduled party!

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kevinwang
Wow, this and the OP are incredibly sick.

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ytham
Thanks for sharing! Really cool drink robots in the link! :)

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markbao
Very cool! From a health perspective, has anyone looked into whether these
homemade machines for food/drink are safe for consumption? I see that the
tubing in the materials list is FDA-approved, but has there been any work done
on the other stuff? And with alcohol specifically, are there any potential
complications?

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arm55
One of the large benefits of peristaltic pumps is that the only thing that the
liquid touches is the tube.

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markbao
Ah, that's great. For those wondering how:
[https://en.wikipedia.org/wiki/File:Peristaltic_pump.gif](https://en.wikipedia.org/wiki/File:Peristaltic_pump.gif)

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changdizzle
awesome, yujiang! it's been cool to see all the hardware stuff you've been
hacking over the past few months, sad i missed this your party (and the bar
mixvah)!

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joezydeco
SmartBar has been around a few years with a ready commercial product:

[http://smartbarusa.com/](http://smartbarusa.com/)

They've found some traction with places like cruise ships and hotel conference
facilities. They can drop one of these at a cocktail hour with a preset spend
limit and the machine will happily pour drinks until the tab is maxxed out.

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mithras
Consider a kickstarter, I'd love to buy one.

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kfnn
Actually, there's one similar, happening now:
[https://www.kickstarter.com/projects/barobot/barobot-a-
cockt...](https://www.kickstarter.com/projects/barobot/barobot-a-cocktail-
mixing-robot)

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emhart
And another that ended not long ago:
[https://www.kickstarter.com/projects/partyrobotics/bartendro...](https://www.kickstarter.com/projects/partyrobotics/bartendro-
a-cocktail-dispensing-robot)

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arm55
Awesome. I'd really love to see one of these that's good enough to actually
use at scale at a large party. This one looks closer than a lot of the others
that I've seen. Perhaps higher quality peristaltic pumps (higher flow rate,
less noise) in combination with more ingredient chambers would push it over
the edge.

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pa5tabear
We really need this for Soylent, and I remember there was talk about this on
the Soylent forums soon after they got going.

Does anyone know specifically what the issues are to creating a Soylent bot?
Or is it in the works?

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fest
Aren't the linked peristaltic pumps a little bit too slow for this purpose? It
would take 3 minutes to fill 300ml of soft drink on top of 200ml vodka.

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chrissnell
It would take quite a pump to match the speed of a skilled bartender with a
soda gun in one hand and a vodka bottle in the other.

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VLM
You might be surprised at what compressed air and a liquid siphon tube can do
with a vodka bottle. 100 psi rated, extremely fast acting air valves are not
that cheap and you need to filter and regulate the air and slow leaks make a
mess and some dripping is inevitable, so "the scene" tends to now use tubing
pumps as seen in the linked article.

Another tech thats been popular over the years is just tipping the bottle,
which has the advantage of putting on quite a show and the disadvantage (or
maybe not?) of splashing. You need a beefy servo because the center of gravity
and torque are going to vary as the bottle empties.

Finally another tech often implemented in these robots is running the
receptacle on an accurate-ish lab scale. Gram level accuracy is probably good
enough although 0.1g accuracy would be better.

Its an old idea thats been around since at least the 80s home computer era,
its been fun watching reimplementations and new ideas and new techs.

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TTPrograms
I've always preferred the compressed air approach, but mostly because of cost
- those peristaltic pumps are pretty pricy if you want to get 12ish bottles in
there. I was under the impression that you could use relatively cheap
pneumatic solenoids like this [http://www.amazon.com/Vdc-Normally-Closed-
Solenoid-Valve/dp/...](http://www.amazon.com/Vdc-Normally-Closed-Solenoid-
Valve/dp/B007D1U64E/ref=zg_bs_1265148011_4) at ~$5 rather than ~$14. Do you
think that it's important to get high quality valves? My plan was to use a
scale and do some feedback control to compensate.

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VLM
Hmm those are cheap, at $5 the old aerospace approach of a parallel/series
high reliability network sounds like the cheapest way to prevent slow leaks.
Draw 4 valves with two in series and two strings in parallel and no failure
mode of any individual valve either stuck open or stuck closed can cause an
overall mission fail. Another way to deal with slow leaks is a small
intentional air leak on the top of the liquor bottle and trust your weight
scale feedback because the output flow rate will be lower but how much lower
will depend on the intentional air leak. So 10% of incoming air leaks out,
well, thats OK if it prevents slow dribble.

WRT to quality valves if you have a slow leak in the air input valve, even
just a drip per minute, you'll slowly drain the bottle while it sits there. A
more complicated arrangement with more valves can vent the bottle when its not
supposed to be pumping which helps.

Your scale idea is excellent and I've seen it done. If you're sufficiently
motivated its a great platform to play with PID controllers or at least PD
(not I) control theory.

For a literature search I've seen this kind of machine in make magazine maybe
in the 00s or at least a couple years ago and in some 80s era home computer
magazines. It fell out of favor in the 90s or maybe I wasn't paying attention.

Advanced systems put a slight vacuum on the delivery hose to prevent dribbling
although there's obvious cross contamination fears. From memory this was part
of the reason the "tip the whole bottle with a R/C servo" guy took that
approach, side from being visually more stunning. I remember that guy writing
about an air traffic control issue where you can't have the neck of two
bottles in the same airspace simultaneously, so extra delay timing is
critical, can't immediately drop one bottle at the same instant one is lifting
up.

I also recall reading about a design involving "hit the wine-in-a-box button
with a servo horn" although that had variable flow rate problems and splashing
issues, which might be worked around.

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TTPrograms
The parallel/series approach sounds really interesting - I'll have to look at
that. On the other hand, if you wanted to reduce valve count, you could even
do charlie-plexing! Then you can get 2*sqrt(N) nice valves to control N
bottles. That would be really cool. Now somebody's just got to build the 100
bottle bartending robot.

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Gobiel
You do not seem to put the emphasis on what's interesting: Is the drink
actually any good?

Great job, obviously!

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gamesbrainiac
You still have to put in the ice youself. Perhaps version 2.0 will have this
feature :P

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leonhuu007
You should monetize it soon. I would be one of your first customer. Great Job!

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joshmn
This is now my summer project. Thank you!

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Zigurd
I'll have a soylent and vodka.

