Smart Light Project

Smart living room lamp that turns on when the room gets dark

Project Overview

The ESP32 Microcontroller measures the light in the living room as well as the corresponding time and sends an HTTP POST request to an IFTTT webhook service that then turns a WeMo Smart Plug on/off. The process is overriden from 11:00pm to 9:00am.

ESP32 Setup

There are two ESP32 circuit diagrams that reflect the testing and the final deployment circuits. The difference between the two being the presence of an LED that represents the HTTP request being sent. Here you can see the final version of the circuit:

Final Circuit

Actual Final Circuit

Code Development

• Host Device = Windows 10 desktop running Windows Subsystem for Linux (v1) with Ubuntu 18.04.4 LTS
• Embedded Code IDE = Arduino IDE (v1.8.13)
• Host Code IDE = VSCode (v1.50.0)

Materials

• ESP32 (Affordable microcontroller with bluetooth and WiFi networking capabilities)
• WeMo Smart Plug (Network-controlled current relay that interfaces with IFTTT)
• Photoresistor (Simple and cheap light dependent resistor)
• Jumper Wires
• Small Breadboard
• 5V DC Power supply (Standard 5V DC power supply with micro-USB connection for ESP32)
• Resistors (Specifically 10kΩ and 100Ω, present in many electronic kits)
• LED

Getting Started

To replicate this project, follow these steps:

• git clone https://github.com/alemorm/SmartLight.git ~/

• Write the name of your network within the double quotes next to wifiName in the file auth.keys_template and rename it to auth.keys

• Write the password of your network within the double quotes next to wifiKey in the newly renamed auth.keys file

• Create an IFTTT account

  • Connect a Webhook service to your account

    • Click on Documentation after you added the webhook and copy the key value within the double quotes next to the iftttKey in the auth.keys file

  • Connect a WeMo smart plug to your account

  • Create the following IFTTT applet:

    • If This -> Search and select Webhooks
      • Under event name write lamp_on
    • Then That -> Search and select WeMo Smart Plug
      • Select the Turn on action

  • Create the second following IFTTT applet:

    • If This -> Search and select Webhooks
      • Under event name write lamp_off
    • Then That -> Search and select WeMo Smart Plug
      • Select the Turn off action

• Download and install the Arduino IDE (can be any PC/Mac/Linux OS version):

• Open the Arduino IDE and follow this quick tutorial to add the ESP32

  • This specific project used the NodeMCU-32S variant of the ESP32 but make sure to check which ESP32 variant you are using

• Follow this additional quick tutorial to add the Arduino ESP32 filesystem uploader plugin tool to the Arduino IDE that lets you add files to the ESP32 using the SPIFFS filesystem:

  • Once the tool has been configured, make sure to select Tools>ESP32 Sketch Data Upload to upload the auth.keys file to the ESP32

• Then, follow this circuit schematic to set up the testing light-sensing circuit.

• Once the Arduino IDE has been configured to use the ESP32S, open the TimeLightClient source file on the Arduino IDE and upload the code to the board (making sure the debug_var is set to 1 to see the serial output).
  • Once the code is done compiling and uploading, open the Serial Monitor under Tools>Serial Monitor and monitor the light and date/time values.