PourFection Makes Piping Hot Pour-Over Coffee at the Touch of a Button

We all want delicious pour-over coffee that would impress our most hipster friends, but paying $8 plus tip for a cup at a local cafe every morning is a fast track to poverty and making a cup at home is nearly impossible while still in a bleary state of half sleep. But despite its reputation for being fancy, pour-over coffee is really simple to make — it is just time-consuming. For an electrical engineering capstone project, Lance Go and Sean Morton decided to build a machine called PourFection that makes pour-over coffee at the touch of a button.

As the name implies, pour-over coffee is made by pouring hot water over ground coffee beans. The water seeps through the grounds, then drips through the filter down into the mug. But this is a laborious task, as you have to slowly pour the water while carefully wetting all of the grounds—and most guides recommend that you break the process down into multiple pours. That labor is what separates pour-over coffee from your grandpa's boring old drip coffee. The similarity doesn't seem to have been lost on Go and Morton, because PourFection works a lot like the Mr. Coffee machines that litter thrift store shelves.

An ESP32 controls PourFection's various components and provides a web interface that users can access from their smartphones. A simple electric kettle brings the water up to boiling, which the ESP32 detects with a thermistor. It then activates a peristaltic pump to pull water from the kettle and push it out through a nozzle above the coffee and filter. Servo motors move that nozzle in a circular pattern, ensuring that the water douses all of the coffee grounds. The pump pushes the water through the nozzle with enough pressure to create steam, which is the major difference between drip coffee and pour-over coffee.

An HX711 load cell with amplifier sits below the coffee cup and tells the ESP32 when to stop pumping water. A heating pad keeps that mug warm until the user picks it up. The PourFection enclosure is a combination of aluminum extrusion and laser-cut plywood. Go and Morton designed a custom PCB to connect all of the components, but that shorted and fried during testing. That forced them to use a breadboard for their project demonstration, but the PCB design probably only needs a couple of tweaks to be serviceable.

We can only assume that the pair got full marks for the assignment after giving the professor a little caffeine boost.