Student Turns His Locker Into A Soda Vending Machine

Back in high school, on my summer breaks, ambition was at the bottom of my list. I wanted to hang out with my buddies and do as little as possible. It would never have occurred to me to take on a project. Turns out I could have been doing something cool and setting myself up for the future at the same time. C’est la vie, amirite? 

Instructables user Mistablik had a different idea for how to use his summer break. Headed into his senior year, he wanted to build a soda vending machine for his locker at school. The project would challenge his mechanical engineering and programming skills and take months of planning and building, but in the end he had a unique locker and he was the talk of the school.  

After consulting with some friends about his crazy scheme, Mistablik got down to work, starting with the control panel. He bought an Arduino, coin acceptor, an LCD screen, and a magnetic reed switch, and powered it all with a 21-volt battery.

He figured out how to program it to accept nickles, dimes, and quarters, and to dispense two kinds of soda selected with arcade buttons. 

To make the face of the control panel, Mistablik turned to the school’s laser engraver. 

After figuring out where everything would fit behind it, he mocked up his control panel in Photoshop and CorelDRAW, cut some holes for the screen, buttons, keyhole, coin slot, and displays, then put the laser engraver to work on his simple, classic grid design on black acrylic. 

Of course, the control panel wouldn’t be complete without some anti-theft measures.

Mistablik cut two boards of the same thickness as the lip that the locker’s door rests in, then put a couple of holes in them where a key-driven arm could slide in.  

With the control panel complete, Mistablik made an acrylic box to encase it so it would sit neatly on the lunch box shelf inside the locker.

It holds the battery and the change drawer, and he built in a power switch to turn it off when the locker is closed and a charge switch so he could charge the battery without having to open the whole machine up.

However, when he had all that done, he realized people might be able to cheat his machine…