An internet controlled classic vending machine
A few months ago I picked up a functioning old soda machine off craigslist. This machine was built in 1977 and has been comfortably vending soda the same way for over 30 years. Thats boring, lets make this retro machine a little more modern!
Vender has its credit functions, and dispense button electronically controlled and has two capacitive touch sensors to dispense free soda if you know the secret place to put your hands. It also has a police beacon light atop of it to signal when someone remotely dispenses a can. All of this is on a platform connected the internet, enabling operation from a website (buyusbeer.com) or my iPhone! It makes for a great living room decoration, and always serves up ice cold soda (and beer).
Since I’m moving out and traveling this summer, me and my roommates are selling Vender on eBay. A portion of the sale goes to support the Kiva foundation. Check it out.
Here’s the Phidget 8/8/8 control board at the heart of Vender. This is used to send signals to the relays, and to react to the input from the touch sensors. The control board is connected to an old P4 computer I was able to scrounge up around MIT. The computer runs all the code that lets Vender interact with the internet.
Somewhat like my door, Vender can be controlled from my iPhone. I have two buttons on my home screen, ‘Soda’ and ‘Beer’ that perform their respective functions. This is the easiest way to dispense from the machine! Though a number of times I have pushed it while I’m away only to find a warm beer sitting sitting in the machine when I come back.
Vending machines from this era all equipped with Jones plugs between the coin mechanism and the rest of the machine. The coin mechanism handles the tricky task of accepting money and giving back change, and then just tells the rest of the machine when a soda has been paid for. After trolling the soda-machines.com forums, I learned that to establish credit you just need to momentarily connect pins 1 and 7 on the plug. I snaked two wires to these pins and then connected them with a relay operated from the control board. The original coin mechanism is still plugged in.
The button relays are a bit less elegant. After finding the electrical diagram of the machine from the manufactures website (thanks Fawn Vending Systems!), I cut and stripped the wires coming out of each button’s microswitch. Then I spliced in another loop through a relay so that I can simulate a button press from the control board. The microswitches are still connected so the buttons still works otherwise.
Behind the front panel are two Phidget touch sensors based on the QT110 chip. These sensors works by detecting small variations in capacitiance caused by something like a human finger. They work through any dielectric material (in this case plastic) and don’t require actual touch, only proximity of about 1/4 inch. With the light off on Vender their presence behind the plastic isn’t noticeable.
My roommates (Tom and Jonathan) put together a website and hooked Vender up the general internet at http://buyusbeer.com . Here we stream a live video of our living room and the machine. You can pay $1, see a countdown before the beer comes out, and then watch us drink it. We’re operating it on friday nights and its been surprisingly popular among our friends as well as the reddit community. We don’t really make any money off it, especially considering paypal takes 30cent from every dollar, but we’ve sold a surprising amount of beer.
Me and all my roommates are moving out in a few weeks, so we’re putting the vending machine, electronics, and buyusbeer.com website/domain on ebay. %10 of the sale is going to Kiva. If you’re curious, check out the sale at eBay.