COM-GND Espresso

COM-GND Espresso is an open-source hardware and firmware project aiming to develop a standard set of sensing and control modules for Espresso machines.

With the growing accessibility of advanced microcontrollers and sensors, it has become significantly easier to develop automated control systems. COM-GND Espresso intends to establish a common set of low-cost, plug-and-play electronic components so that attention can be focused on experimentation through software control.

This hardware project is under active development in conjunction with the GND-CTRL software interface.

WARNING: RISK OF DEATH

This project works with 110V AC Current. Use at your own risk.

WARNING: ALPHA STAGE PROJECT

This project is unstable and undergoing active development.

COM-GND Espresso Modules

• Pressure Sensor for pressure profile feedback
• Variable pump power modulator for pressure profile control
• Pressure knob rotary encoder for manual pump control
• BLE (Bluetooth) interface for App control
• Boiler temperature sensor / PID control

  Forthcoming Modules

• Bluetooth shot scale integration
• Water-tank scale for flow profiling

Hardware Stack

• Esp32 DevkitC: Microcontroller with onboard BLE
• Robotdyn AC Modulator: Pump power modulation
• TE Analog Pressure Transducer: 10 Bar boiler pressure sensor
  • Note: For new projects, the Digital I2C version is recomended for easier interfacing with the ESP32
  • Note: adding a pressure sensor requires altering the machine’s internal plumbing.
• Vishay Temperature Sensor

Development

This is a Platform.io based project using the Arduino framework.