The main moto of this project is to develop a home automation system using an Node MCU board and amazon echo dot (alexa). As technology is advancing so houses are also getting smarter. Modern houses are gradually shifting from conventional switches to centralized control system, involving remote controlled switches. Presently, conventional wall switches located in different parts of the house makes it difficult for the user to go near them to operate. Even more it becomes more difficult for the elderly or physically handicapped people to do so. Voice controlled home automation system provides a most modern solution with IOT Devices like Alexa, Google home mini etc.
In order to achieve this, a relay module is interfaced to the Node MCU board at the receiver end while on the transmitter end, where loads are connected. To operate any electrical appliance using alexa, you can simple say "alexa, turn on light 1" but before do that you jsut ask alexa to find your devices by saying "alexa, discvoer near by devices".
Step 1: Things You Need
3. power supply (5v, 2 amp)
you can make the connections like in the picture
(Note: try to connect only 3 devices to node mcu, as if you connect 4 devices nodemcu unable to work properly, as expected (from our past experience))
Step 2: Source Code &instructions
code you can simply down load then upload to node mcu.
once everything was done (code uploaded to nodemcu+alexa has been set up with wifi)
Some times alexa wont detect your device, then try disable smart home skill then try again , if it didn;t worked then try to delect all the connected devices then start discover new devices by saying "alexa, discover near by devieces" try again (2 to 3 times).
Cheers to you all.....................