There are lots of people out there who enjoy the process of baking tasty treats just as much as they enjoy eating those treats. But sometimes you just want to eat a cupcake without going through the hassle of baking. With the pandemic raging on, you probably want to avoid going to your local bakery to purchase fresh cupcakes. That leaves only one option: spend an absurd amount of time building a complex machine that is capable of automatically baking and decorating cupcakes for you on demand. That’s exactly what YouTuber Skyentific has achieved with his Arduino-controlled cupcake robot.
There are plenty of other food-making robots out there, but this one is impressive in both the quality of its construction and its capabilities. It handles the entire cupcake production process, from dispensing premixed batter to decorating the cooked cupcakes with frosting. Many of the principles here are similar to those behind 3D printer and CNC machine design, just with the axes rearranged completely. The robot is setup in an assembly line style, with multiple stations along the horizontal axis. The first station contains a microwave oven, the second station dispenses batter, and the third and fourth stations apply frosting and other viscous toppings.
It should probably go without saying, but microwaves are potentially dangerous and you should not mess around with them if you don’t know what you’re doing. Even Skyentific admits that his microwave oven was leaking, despite the use of a shielded enclosure. Please don’t accidentally cook yourself.
The frame of the robot is constructed mostly from lengths of T-slot aluminum extrusion and lots of custom 3D-printed, steel, and aluminum parts. The three dispensers are repurposed motorized caulk guns that are controlled by an Arduino Uno through relays. Stepper motors are used to move the cupcake platform back and forth along the horizontal axis and to lift the platform up when it reaches each station. Limit switches on the first station detect when the platform is properly seated in the microwave oven in order to reduce microwave leakage. The platform contains an additional motor to spin the cup in order to evenly cook the cupcake and distribute toppings consistently.
As you would imagine, Skyentific had to go through a lot of trial and error to find the ideal settings for cooking time, amount of batter dispensed, and so on. Eventually, he was able to find settings that thoroughly cooked the cupcake all the way through without burning anything. The toppings were something of a disaster, because the hot cupcake causes them to melt and run off the sides. But that is solved pretty easily with a delay for cooling or by using different toppings. Either way, the machine works well and the cupcakes even seem to be edible!