Smart Coffee Replaces Espresso Machine Controller With Arduino, Sensors

A common hacker upgrade to an espresso machine is to improve stability and performance with a better temperature controller, but [Schematix]’s Smart Coffee project doesn’t stop there. It entirely replaces the machine’s controller and provides an optional array of improvements for a variety of single-boiler machines (which is most of them).

Smart Coffee isn’t free, it costs 16 NZD (about 10 USD) but there is a free demo version. There is no official support, but there are wiring guides and sources aplenty from which to purchase the various optional parts. It runs on an Arduino MEGA 2560 PRO (or similar microcontroller) and supports a wide array of additional hardware including pressure transducer, water level sensor, flow meter, OLED display, and more.

Modification of one’s espresso machine is a rewarding endeavor, but the Smart Coffee project provides a way for one to get straight to the hacking and function modifying, instead of figuring out the wiring hardware interfacing from scratch.

We’ve seen [Schematix]’s work before with a DIY induction heater which showed off thoughtful design, and it’s clear he takes his coffee at least as seriously. Check out the highly comprehensive overview and installation video for Smart Coffee, embedded just below the page break.

Thanks to [X-Cubed] for the tip!

16 thoughts on “Smart Coffee Replaces Espresso Machine Controller With Arduino, Sensors

    1. Here is a little analog and more risky one (according to the comments some hacks of this kind tent to explode like granate).

      I still dont know why the coffee of this little pots tastes so good. I know if water boils its to hot and to hot water extract much of untasty bitter flavour out the coffee. But this in this little wonder pot the water boils and the extracted coffee tasted cacao like.

  1. I was looking at the assets they have to download. There’s a header file, some documentation and a wiring diagram. The “preview” version of the software looks more like part of an SDK rather than a preview of their product. And are you supposed to be switching the neutrals rather than lives when controlling things with relays? Otherwise it looks like a nice product. Don’t get me wrong. I’m not criticising the product, just making an observation about the weird way they’re showcasing it.

      1. _Inside_ a machine, you can do what the hell you like. If you were taking the SPST switched output to a socket, then you should switch phase.

        The choice comes down to a designers choice.
        a) Is it better to have the control circuitry at ground potential? If you do, then there may be fewer issues of EMI, some level of intrinsic safety for servicemen, and some inherent safety if the isolation barrier between the user and the control circuitry breaks down. (i.e. you touch the button contacts or display conductors).
        Then if you have a directly driven triac, you want to switch neutral.
        Another case is if you might think of a short to ground on the pcb. In this case pcb fault currents are limited by the resistance of the heaters, solenoids etc if you switch neutral. You also don’t have to bring the phase wire onto the pcb at all.

        b) Alternatively you might think that the element and other switched parts represent a greater hazard than the controller. Another case might be what happens when an internal short in the heater to ground occurs. Is it really a good idea to leave one side of the heater connected to mains 24/7 while the machine is unattended?
        In this case you would prefer to switch Phase.

        If you prefer both a and b, then you isolate the switch with an opto or use a relay. Another reason to use an opto, is that the failure mode of a triac/fet/ect is often to connect the output to the gate, and thus blow up the whole control circuit. Using an opto limits the damage to the opto and switch.

  2. A few years ago I wanted to have our Coffee machine more smart do I created this :

    It’d based on a ESP32 and has a nice display with touchscreen… I wanted to look into pressure sensor aswell but decided that if the temperature is controlled well enough, then pressure will be good enough.

    No need to do anything mechanically in your machine, just electronics :)

    1. Will take a peek and see if there are any great ideas… But the truth is, mine works pretty wel, my wife knows how to use it and I can turn it on and off remotely… and does have automated power savings, sends data to mqtt… It actually already has all the bells and whistles of my needs…

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.