Earlier this year, the Uk’s first and only emo band Los Campesinos! released an album for the first time in seven years. The introductory song on the album is titled “The Coin-Op Guillotine.”
I created a real-life version of The Coin-Op Guillotine that dispenses stickers of severed heads.
I created the drop mechanism using two motors and a photoresistor; the first motor turns a gear, which winds up a string that raises the blade.
Once it reaches the top and covers the photoresistor, the second motor engages and disconnects the gears from one another, allowing the weight of the blade to fall. The second motor pushes the gears back into alignment, and the mechanism is reset.
The sticker extruder used one motor to spin a set of gears connected to a bolt with two rubber O-rings on top of the sticker roll. Because the motor gear sits higher than the bolt gear, it can generate more torque, which pushes the stickers forward.
Since the blade would be in the way of the sticker slot, this mechanism engages after the pulley motor. That way, the blade is out of the way, and the stickers can be smoothly guided to their deaths.
The structure of the guillotine was made with layers of laser-cut plywood, which were glued together. At one point, the wood was causing too much friction in the slides, so I ended up crushing up graphite and rubbing it along the insides. There were a lot of micro-tweaks like that throughout this project.
This project focused on electronics, soldering, mechanical design, programming, laser cutting, and 3D printing.
In total, I used two sensors and three motors, including a coin reader, a photoresistor, two steppers, and a servo, all of which are connected to an Arduino Uno with code written in the Arduino IDE. All 3D modelling was done in SolidWorks/Onshape, including the gears, brackets, and servo arm.
In the end, I am proud of what I was able to accomplish with this project. There were bumps along the way, and despite my complicated mechanisms, it’s functional(!) and looks kinda sick(if you're into that goth stuff).