Arduino IoT Cloud con ESP32, Relé (relay) y Sensor DHT22. Guía completa paso a paso desde cero

The video is a comprehensive step-by-step tutorial on using the Arduino IoT Cloud with an ESP32 board, a Relay Module, and a DHT22 temperature and humidity sensor. Key technological concepts and product features covered include:

1. Arduino IoT Cloud Setup
   • Creating a free Arduino IoT Cloud account.
   • Explanation of Arduino IoT Cloud plans, highlighting limitations of the free plan (max 2 "things," 10 variables, 1-day data retention).
   • Definition of a "thing" as a virtual object in the cloud representing connected devices and their data.
2. Hardware Components and Wiring
   • Use of ESP32 (NodeMCU 38-pin model) as the microcontroller; alternative ESP8266 support mentioned.
   • Wiring details for the DHT22 sensor (3.3V power, data pin with 10k resistor to 3.3V, ground).
   • Wiring for a Relay Module (signal pin to ESP32 GPIO 27, 5V power, ground).
   • Important note on voltage differences: DHT22 uses 3.3V, relay uses 5V.
3. Arduino IoT Cloud Device and Variable Configuration
   • Creating a "thing" in the cloud and adding variables: temperature and humidity as float (read-only), relay status as boolean (read-write).
   • Variable update policies set to "on change" to optimize data transmission.
4. Software Setup and Code Upload
   • Installing necessary libraries (DHT sensor library via Arduino Library Manager).
   • Using the Arduino IoT Cloud web editor to generate most of the code automatically.
   • Adding minimal custom code to read sensor data and control the relay based on cloud variables.
   • Uploading code to ESP32 after selecting the correct board and COM port.
   • Installing and running the Arduino IoT Cloud agent on the PC for device communication.
5. Dashboard Creation and Visualization
   • Building a dashboard in Arduino IoT Cloud with widgets:
     • Gauge widget for temperature (range 0-50°C).
     • Percentage widget for humidity (0-100%).
     • Button widget for relay control (on/off).
   • Customizing widget sizes and layouts for better visualization on desktop and mobile.
6. Remote Monitoring and Control
   • Accessing sensor data and relay control remotely from any internet-connected device via Arduino Cloud dashboard.
   • Using the free Arduino IoT Cloud Remote app (available on Android and iOS) to monitor temperature and humidity and toggle the relay from a smartphone.
7. Practical Demonstration
   • Testing relay control by turning a hair dryer on/off remotely via the dashboard and mobile app.

Main Speakers/Sources:

• Carlos (channel owner and presenter)
• Arduino IoT Cloud platform and documentation
• ESP32 and DHT22 hardware modules
• Arduino IoT Cloud Remote mobile app

This tutorial serves as a beginner-friendly guide for integrating sensors and actuators with the Arduino IoT Cloud, enabling remote data monitoring and device control using ESP32 and cloud services.