[Qdot] came up with a simple way to dosing out liquids to use in his Bartris project. As you can see above, flexible tubing is connected to some inverted bottles that house the liquid. A chopstick is attached to a board on one end, and via string to a servo on the other. When the servo turns it pulls the chopstick tight against the board, cutting off the flow of liquid through the tubing. This isn’t as elegant as the system the Bar2D2 uses but it’s a heck of a lot less expensive.
You can check out some of the build pictures in his Flickr pool. He’s included this concept in a project he calls Adult Mario. Watch the video after the break but the quick and dirty is that the more coins you score in Super Mario Brothers, the more beverage is rationed out into your cup. Ah, human lab rats, is there nothing they won’t do for booze?
[youtube=http://www.youtube.com/watch?v=7kiKE3lif8Q]
[via DVICE]
Anyone else skim through and see ‘adult mario’ and ‘roboexotica’ and get kinda scared?
i would hope that the servos pull the chopsticks to open the valve, rather than the other way around, as then they would normally closed when not powered.
upon reading some of the flickr explanations, it seems i am wrong. so, if he loses power to the servos, then it all dumps out…
i now want to explore this and other valve mechanisms for a watering system.
Why not make the hoses have an airtight seal, then control the vacuum inside the bottle rather than soaking a chopstick in booze (ew, rotting wood)? The bottle won’t pour unless there is a vent.
Advantages:
Accurate dispensing, plus there is nothing standing between the liquid and the cup besides hose and vacuum. No nasty chopsticks.
Whoops, read through it again and realized chopstick is not touching the liquid. Point still stands — a failure mode of the vacuum-based system would be zero leaks.
Use a heavy metal cone in a funnel-type device. If the servos are powered off, the cone drops and makes a seal. Also, less strain on the servos this way.
depending on the servos used and how they are used i would guess the gear ratio makes them pretty hard to turn by hand when they aren’t powered.
Nice design. It is rather funny that I found this now. Across the room from me is my own version of a drink dispensing machine. Personally I think ours is better. All it does is dispense drinks. We are using a PIC microcontroller and solenoid valves. Soon I will post instructions and pictures somewhere (I hope no one kills me for using instructables).
@sarsface: I also got scared when he talked about the vibrator timing, so you “can feel Mario slide the flagpole.” Vibrators and flagpoles shouldn’t be used in the same sentence, if you ask me.
I LOVE IT!
WANT
I agree that the dispensing could have been done better. The vibration module was a bit strange to me as well, why not have it go off every time you break a brick or something?
@bob
Instructables *can* be done tastefully. If you include pictures and have a decent set of instructions/part list I’m sure noone will kill you.
Just don’t half-ass it like most Instructables users.
I’m with the previous commenters, it seems like this is unnecessarily Rube Goldberg-ish. If you already have the mechanism in place to control servos to meter flow, there are much more logical and effective ways to employ those servos than pulling chopsticks with strings.
Even if it is an issue of trying to cut costs by not buying valves, something could have been rigged where the servo horn pinched the tube against a stationary object, or even just kinked it.
Ok, the disclaimer: I like this project, and I support the solution that he found of using servos to pull on the chop sticks.
In the interest of brainstorming: This could be kept inexpensive remove the worry about the power loss issue if the servos were used to unkink/uncompress the tube. Perhaps a light spring-clamp could be found that would allow the servo open it for a short period.
it’s roboexotica not roboerotica.
Here is the link to some pictures of my setup. There are lots of features that I need to add. Our solenoids were not too expensive ($13 apiece). I want to add more features before I post instructions. I also have to wait till after finals week so I have some free time.
I don’t think vacuum based system would work for carbonated beverages like coke, since they continually release CO2. They’d just drip constantly.
and then you lose power and all your precious liquids
I seem to remember reading years ago about pulling some 12v airflow (exhaust/smog equipment) solenoids out of cars at the junk yard. These can be used for liquids and are really cheap out of junked cars. Not sure on using old smog valves for liquids to be consumed by humans, but maybe you could find new ones surplus pretty cheap.
The thing I read was talking about using them as a plant watering system. Maybe if you run enough water, or solvent then water, therough them they would be pretty clean. Again, maybe not clean enough for human consumables.