A hard-to-build fridge makes grabbing a beer easy
Posted 06.13.2011 at 10:30 am
12 Comments
Beer Me
Ryan Rusnak programmed a three-second delay between trigger and release so you have time to put down your iPhone and set up for the catch.
John B. Carnett
I have a background in programming, but a program by itself has limited use. I was like, man, I need to make a project that will actually control something. I had my old mini-fridge from college lying around and, I thought, how about an iPhone-controlled drink vending machine? So I did it . . . and it sucked. You could control it from your living room—or from China—but the cans just rolled out onto the floor. It was a pain to walk over and get them. I wanted to get a beer to travel from the fridge across a room with minimal effort and maximum cool.
I called my friend Graham Phero, and we started building a new version. We thought it would be awesome to use compressed air to propel the cans, but we had no idea how much pressure to use. We started with 100 psi and destroyed a can of beer on the ceiling of a garage. After that, we started at 10 psi and worked up.
Slowly the rest of the project began to take shape. The vending mechanism is a series of slanted shelves built inside the fridge, with a servo at each end. The beer is funneled into a cannon, and the whole thing is mounted on a lazy susan, allowing it to turn so you can aim the throw. My friend Josh Lilly helped me design an iPhone app that could select a beverage, aim the cannon, and fire it.
How It Works
Time: 2 Days
Cost: $400
Drink Storage: The shelves angle down slightly so the cans roll to the dispenser. At the lower end, an arm attached to a servomotor holds the cans in place. When the servo receives a signal to retract, a can is sent through a cutout in the fridge and into the cannon barrel.
Air Supply: An air compressor plugs into the wall and connects by a hose to the expansion tank, a short, capped PVC pipe. A regulator valve between them controls the pressure in the tank. Optimal pressure for lobbing a can of beer 15 feet: 45 psi.
Valve: A sprinkler valve plugs into the expansion tank and holds the pressurized air in until you’re ready to fire. It’s attached to an electric relay that will open it for a tenth of a second, releasing the air from the tank and forcing it down the barrel.
Barrel: The barrel pipe should be just wide enough to accommodate a can without creating excessive friction. Too much space between the can and the barrel wall will let air escape past the can and diminish pressure.
Inside the Fridge: Each type of beer and soda has its own shelf. John B. Carnett
Turret: The whole assembly sits on top of a Lazy Susan. Using a fixed joint that provides a 90-degree turning radius, a servo moves the assembly to aim the throw.
Microcontroller: An ioBridge 204 microcontroller, which lets users control devices via the Internet, is the brains of the operation. It connects to the vending and turning servos and has an Ethernet port to link to the Web.
Relay Board: When the app commands the robot to toss you a beer, the message is directed to the relay board, which directs a pulse of current from a nine-volt battery to the sprinkler valve, opening it momentarily so the cannon can fire.
The App: The vend button sets off a series of commands. First the servo for the selected drink’s shelf drops, pausing to let a can roll by. The door on the front of the fridge housing opens, and you aim with the left and right arrows.
Rusnak is getting a master’s degree in Human-Computer Interaction at Carnegie Mellon University in the fall. You can get full instructions to build the project and search for “Beer Cannon Controller” in the iTunes store to download the app for free.
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Congratulations, sir! You've made the world a better place.
I applaud your efforts for your positive ingenuity. At least one genius in the world is NOT making a virus or hacking into someone else’s computer. Finally an invention that is beneficial to all mankind. I like to say, THANK YOU SIR, from planet EARTH. Please let me know when these units come on sale!
@Bubba
Who said he isn't making virus' or hacking into your computer in his free-free time? Your lack of critical thinking is disrespectful to all us other programmer/hackers. Aaaanddd... how exactly is this beneficial to all mankind again?
what a dumb, pointless invention. i wonder how much money went into this?
How is the foam management? Range?
@JediMindset...launching massive sorties of beer will overwhelm your jedi defenses, rendering you unconcious and then it will drown you with the remaining beer, not a pointless invention after all
@drchuck1
lol yeah but i will use my jedi powers to cripple the machine and throw the beers at you.
damn it! :)
This promotes laziness
lol
Epic. I could use one of those in my garage.
The iPhone 4S doesn't offer much in the way of camera controls. The sensitivity settings, white balance and exposure, for example, are all set automatically with no way of adjusting them prior to taking a shot. There's not even an exposure compensation facility to tweak the exposure. A camera manufacturer wouldn't be able to sell a compact camera with such a limited level of control unless it was for a child. However, it does make the camera of this smartphone very easy to use and of course extra functionality can be added via apps. One useful option that is available is the ability to manually select whether the flash fires or not. Those who prefer to handover complete control can leave this set to 'Auto' - and generally we found it fired at the correct points, often appearing to improve shots we considered already well-lit. The flash is weak, but it's useful for illuminating very dark scenes or adding a little sparkle to eyes in daylight. It's a very small light source, so if it is the main one for an image, expect strong shadows and highlights – it's not the most flattering option for a night-time portrait, but very strong for a single LED. A tap of the screen is all that is required to set the focus point. The camera then usually does a quick backwards and forwards focus adjustment before the subject is made sharp. There's no clear focus indicator, the subject just looks sharp when the focussing has completed. Although the touchscreen is core to the iPhone, Apple hasn't given the camera a touch-shutter facility. This would trigger than camera to focus and take the shot with a single touch of the screen. Instead, after choosing the focus point, the shutter icon needs to be hit to take the shot. The 'up' volume control can now also be used as the camera shutter button too - however, it was very stiff indeed on our test sample, meaning there was an element of shakiness about some of the photos that simply pressing the screen could accomplish. However, it's still a nice touch to have - taking pictures of yourself is much easier with this as an option. Although there is no optical zoom facility, the iPhone 4s camera allows users to zoom digitally into the scene using the pinch to zoom option on the touchscreen. Plus you could always look SUPER COOL and get one of those optical attachments for the iPhone 4S to make it into a longer range shooting device - but you'd have to be really dedicated to do that. Rather than reducing the size of the images, however, the iPhone interpolates the digitally-zoomed shots so they have the same 3264x2448 pixel dimensions. On-screen icons provide access to the secondary camera and the grid display, flash and HDR options. These icons can be difficult to see when you're shooting from an awkward angle and it's easy to touch one accidentally when you are trying to set the focus point. It's helpful that, if the camera is active when the iPhone 4S is put into sleep mode, the camera is available as soon as the lock screen is swiped open. You can also jump straight into the camera from the lock screen with a double tap of the Home Button, although you can only see the snaps you've taken from that session, meaning you can't sneak into the photo gallery of a code-locked iPhone.