Development and implementation of a system for acquisition and processing of sensor data.
As project work during my further education as a mechatronics technician, I did the following IoT project:
Project
Project description
Goals
- Get an overview of a complex central heating system
- Control processes
- Optimize the existing control
System diagram of the present heating system with planned measuring points
Requirements
- Equip the heating system with sensors
- Collect sensor data
- Present sensor data on a website
- Run data-based actions
Course of action
Concept
The idea was to develop a custom system, instead of using proprietary components like a PLC or industrial sensors.
This would result in a scalable and cost-efficient solution using common consumer electronics.

Concept schema of the developed system
Tasks
- Developing a custom PCB
- Choosing components
- Designing parts
- Manufacturing assemblies
- Developing software
- Testing and evaluating
- Documenting the project in a technical report
Conclusion
Implemented Features
-
Multi-purpose PCB:
- Read various sensors
- Control things with relay and MOSFET outputs
- WiFi Capability
- Send sensor data to central server
- Store data in a database
- Access data via a web interface
- Analyze data, send notifications
- Send commands from server to PCB
Projects based on this one
In this particular project a central heating system is monitored and controlled using the developed pcb.
However, the multi-purpose PCB was planned to be used in various other, future projects.
Developed PCB used for controlling the Electric Armchair V2
Components
Hardware
Custom PCB
- 100x100 mm 2-layer PCB
- ESP32 microcontroller
- 2x TPS562200 Voltage regulator
- 6x Si2302 N-Channel MOSFET
- 2x IRF7455 N-Channel MOSFET
- LEG-12 Relay
- Buzzer, SMD LED
- Screw terminals
- Various passive components
Sensors
- 25x DS18B20 temperature sensor
- 1x PT100 temperature sensor
- 3x Pressure sensor
- 4x Current sensor
- 1x SHT10 temperature, humidity sensor (outdoor)
- 3x SHT33 temperature, humidity sensor
Mechanical
- 3d-printed housing
- Custom brass adapters for pressure sensors
- Custom aluminium holders for temperature sensors
Software
Programming
- ESP-IDF Espressif IoT Development Framework (C)
- Node-Red (JavaScript)
- MySQL (SQL)
Protocols
- MQTT
Tools
- KiCad
- Inkscape
- LaTeX
- draw.io

ESP toolchain (source: espressif.com)
Logos of software used in this project




