ESPress Io T

Abstract

1. Introduction

This project covers somewhat advances features for an espresso machine controller. The basic idea was to have reproducible "espresso results" due to temperature regulation and being able to fine-tune. Especialy small machines have a low heat capacity and quality suffers a lot from different heat-up-times and high hysteresis in standard temperature switches. This work is based on my previous work with with IoT, MQTT and my small controller cofcon. As always - take care, you are working with high voltages and you are switching loads up to a few Kilowatts. Please be sure yo know what you are doing, always disconnect and unplug you machine before installing electronics components, choose your components (cables, connectors, sensors, SSR etc.) wisely...

2. Objective

This project covers somewhat advances features for an espresso machine controller.

This project demonstrates how C++, ESP8266, Arduino can be applied to a real-world Internet of Things (IoT) problem.

3. Key Features / Modules

• very fast and accurate adaptive PID-Controller for the heater of your espresso machine (heat-up-time about 2 minutes, stability/RMS of ~0.15 °C)
• Telnet-Server for PID status (analogous to serial terminal)
• MQTT-Interface (needs [PubSub-Client][4])
• OTA-Flash enabled (over-the-air, flash firmware via upload in WWW-Interface)
• Serial Interface for testing, debugging
• JSON-Config in internal SPIFFS (uses [ArduinoJSON][5])
• Re-Written auto-tuning-loop to optimize PID parameters
• integrated simulation to test features and functionality

4. Technology Stack

• Espresso Machine (Gaggic CC, Rancilio Silvia etc.)
• ESP8266 with [Arduino for ESP8266][1]
• [ArduinoJSON v6][5]
• [Arduino-PID-Library v1][2]
• [ArduinoStreamUtils][6]
• a suitable temperature sensor (e.g. TSIC 306 - [library here][3])
• a SSR which is capable of switching your heater, has a low trigger threshold and does not draw too much current (otherwise you will toast your ESP8266)
• some electronics skills

5. System Requirements

General requirements for this technology stack — check the README for exact versions.

• Arduino IDE / PlatformIO or a C++ compiler (g++)
• Target board (e.g. Arduino, ESP32) where applicable
• Git (to clone the repository)

6. Installation & Setup

git clone https://github.com/Schm1tz1/ESPressIoT.git
cd ESPressIoT

Full setup instructions are in the project README.

7. Future Enhancements

Suggested extensions you can add to make this your own project.

• Add a mobile dashboard using Blynk or Firebase
• Store readings in a cloud database for history charts
• Add alerts via SMS / Telegram when thresholds are crossed

8. Viva / Review Questions

Common questions examiners ask for projects in this domain.

1. Which microcontroller / board and sensors are used and why?
2. How does the device send data (Wi-Fi, MQTT, HTTP, Bluetooth)?
3. Where is the sensor data stored and visualised?
4. How is power consumption managed?
5. How would you secure the device and its communication?

9. Source Code & License

This project is developed by Schm1tz1 and published on GitHub under the GNU General Public License v3.0. Please follow the license terms and credit the original author when you use or modify this code.