Guidance on Robotic Bartender

Hello,

I'm looking to build a robotic bartender.

I saw some examples like these:
Example 1
Example 2
Example 3
And the list goes on...

In examples 2 & 3 I noticed that the drinks go into a reservoir and then get dispensed out. What is this reservoir called and where can I find one?

I'm thinking of going with a design like the one in example 1 but the conveyor concepts (in examples 2 &3) are nice too. Which design would be more practical to hold 12-15 bottles?

I'm looking for some guidance on what materials I would need, where to get them, what they're called, and which pumps are best (and how to control those pumps with an Arduino if they're greater than 5v).

Thanks in advance.

Looks like the dispensing valve on the upside-down bottles is called an 'optic' or 'spirit measure'. You can get them in various volumes: 25ml, 30ml...

It looks like a fun project that you can keep adjusting for years:-) Think about how you will clean this when the party's over. Even with the hose through the cap the soda will still go flat.

I actually knew an Engineer from Texas over 40 years ago that had something similar to #1 in his (huge) camper. His was mounted into the countertop, much like the spigot for his sink (actually right next to it). I was interested so he showed me how it worked. He had all the bottles under the sink, pumps like those shown in #1, but ran all of the little tubes into what was actually the faucet stem of an ordinary kitchen faucet. He didn't use a funnel. Each tube ended about a millimeter above the normal screen in the stem.