This tutorial will create an internet of things sensor node based on an ESP32 development board. This node will use the MQTT protocol to send sensor data over WiFi to a Raspberry Pi based IoT server. This tutorial will allow you to collect any kind of sensor data you like, send it over your network to a MQTT server and visualise it on a Grafana dashboard. This system consists of a series of sensor nodes that send sensor data in a JSON message over the network to a Raspberry Pi via MQTT. MQTT is a network protocol where a client pushes data to a broker, such as mosquitto, and the broker pushes that data to any client that has subscribed to that topic. A topic categorises the data that is sent. Any client that is subscribed to "home/sensor" will be forwarded this MQTT message containing the sensor data. On the Raspberry Pi server, NodeRED will subscribe to this topic, interpret the json message data and then send the data to a database to be stored and used. InfluxDB will store all the sensor data. Then a Graphana front end will query the database in order to display the data we want to see and do a whole host of other things. This is all explained in our Raspberry Pi IoT server tutorial linked below. Helpful links: Source code: https://learnembeddedsystems.co.uk/esp32-sensor-node-source-code Raspberry Pi IoT Server Tutorial: https://www.youtube.com/watch?v=_DO2wHI6JWQ ESP32 Dev Board: https://s.click.aliexpress.com/e/_DcGtTAL Timestamps 00:00 Introduction 00:41 System Overview 01:40 How does this work? 02:58 Payload format 03:16 Required libraries 03:36 Hardware setup 03:51 Arduino IDE implementation 04:28 Programming 10:00 Conclusion You can find more embedded systems tutorials and projects on our website https://learnembeddedsystems.co.uk/ -- Equipment we use regularly -- The following links are affiliate links where we may make a small percentage on qualifying sales through these links. Use the respective UK or US links listed. Budget Soldering Iron: UK: https://amzn.to/3pQpvUu US: https://amzn.to/3bBawIJ Breadboards: UK: https://amzn.to/3solZCe US: https://amzn.to/3dGsHiS Jumper Cables: UK: https://amzn.to/37JfToi US: https://amzn.to/3r384S9 Camera: UK: https://amzn.to/3qKLwFr US: https://amzn.to/3pK0V7C Lens: UK: https://amzn.to/380lQxp US: https://amzn.to/3knH3WL Tripod: UK: https://amzn.to/37H0Nzw US: https://amzn.to/3byKHsV All videos and tutorials on this channel and mentioned websites are for educational purposes only.