Home Automation using Google Assistant & ESP8266

Previously, I posted a tutorial about home automation where I showed you how you can control relays over the internet using an Android app. In this article, I will show you how to configure your home automation system using Google Assistant and an ESP8266.

In this project, you’ll learn how to build a voice-controlled appliance. We’ll program phrases like “Turn on the lights” or “Switch on the fan.”

Sounds interesting right?!

You’re probably wondering if this is another tutorial for Android users. But that’s not the case! Google Assistant is now available for iOS on the App store. So, everyone regardless of smartphone type can take part in this home automation project using Google Assistant.

Before we get started, I recommend reading the following articles:

• Getting Started With NodeMCU
• Controlling LEDs Over Internet
• Home Automation Using Arduino

These posts will give you a general idea about the Web Apps we’ll be using.

If you are into IoT and Robotics, be sure to check out my eBook, “Mini WiFi Robot.” This eBook will take you through all the steps through designing, building, and coding your very own mobile robot.

With that said, let’s get started.

Components for Home Automation with Google Assistant

Here is a list of all the hardware and software components we need:

Hardware Components

• ESP8266 dev board
• Relay module
• Breadboard for prototyping

Software Components

• Account at RemoteMe.org
• Account at IFTTT
• Arduino IDE
• Google Assistant for Android or iPhone

Creating Variables and Devices

First, we have to create a few variables that will control our relays. To create variables, sign in to your RemoteMe account and go to “Variables” and click on “Add.” Fill the information as presented below:

Repeat this process for three more variables for Relay_2, Relay_3, and Relay_4.

After all the variables are created, we need a network device that will connect to our ESP8266 board. To create a device go to the “Devices” tab and click on “New Device.” From the drop-down menu select the last option “New Network Device.”

Here we need to name our device. I suggest using the same names as above so that you’re not confused while coding. Let’s name the device “Google_ESP.” The device ID is ‘1’. After these parameters are filled, hit “Submit” to create the device.

Next, we have to generate the code for the device. To generate code click on the burger menu on the device and select “Code Generator Wizard”.

We will see a pop-up window where we have to select the variables we created earlier. Now click on “Next”

On the next page enter your WiFi credentials so that the ESP can connect to your network.

Next, you can enable a direct connection if you want. This will minimize lag, but it doesn’t matter for this project.

Then, turn on the “Debug” option and click on next.

Download the code. We will edit this code in the next step. Lastly, we need one more device. This will be a web device where we can switch on/off our devices.

To create the Web page, click on “New Device” and select the very first option “New Web Page”.
Name the device ” Web_ESP” and give device ID “2” and submit.

To control the relays we need buttons/switches on the web page. To add this page, first, click on the device “Web_ESP,” and click on “index.html.” From the drop-down list select “Edit with wizard.”

Click on the “Insert Component”, next click on “Components,” and from the list select “Switcher.”

In the name field notice the search icon (magnifying glass). Click on the icon and select “Relay_1.”

Next, you can label the button anything. I labeled it “Relay 1.”

Next click on “Insert” to add the switch.

Similarly, we have to create 3 more switches for Relay_2, Relay_3, and Relay_4.

Set Up IFTTT for Google Assistant

In the previous step, we created variables and devices. We can use this for home automation, as is, but this is pretty boring.

To make it more interesting, we are going to connect our project to Google Assistant to take voice commands and turn on the relays.

First head over to the IFTTT website, and sign up with your Google account.

Note: Make sure you use the same google account you have on your smartphone or the setup won’t work.

Once you log in, click on “My Applets” and then click on “New Applet”

On the page, you will see a heading, “If this then that.” Click on “+this”

In the search box type “Google” and select the “Google Assistant.”

Now select the first trigger “Say a simple phrase.”

Here we will add some phrases we want the assistant to recognize and trigger an action. I used “Turn on relay one” as the trigger, below there are two more options where we can add the phrases in different forms.

Then, in the last field, we have to add a response phrase that the Google Assistant will use to give a reply. I used “Turning on relay one.” You can customize these phrases as you’d like.

Now click on “Create Trigger” to finalize the trigger.

Lastly, select “that.” Now, we will create what happens when the trigger is set.
In the search bar type “web” and select “Webhooks.”

Click on “Make a web request.”

Now go back to RemoteMe and go to the “Variables” tab.

Click on the burger menu on “Relay_1,” and click on “Generate Set Variable Link.”

Toggle on “use post method” and “Boolean”, Click on “GENERATE.”

Copy the link from RemoteMe, and head over to IFTTT. In the URL field paste the URL you just copied. Select “POST” under Method, and content-type “application/json.” Now from RemoteMe, copy the body section and paste it in the body field on IFTTT. Click on “Create action,” and “Finish” to make the Applet.

Now go to “My Applets,” and create a new applet the same as the previous step. This applet will be used to turn the relay off.  Adjust the phrases so that they make sense. Instead of a response “Turn on relay one,” change it to “Turn off relay one.”

In Webhooks paste the same URL link and select method as “POST” and content type as “application/json.” We’ll use the same body as before but replace “true” with “false” in the body section. Then hit “Create Action,” and “Finish” to create the Applet.

Similarly, make Applets for each relay with proper phrases. You should get 8 Applets in total for 4 relays.

#define Relay_1 D1 
#define Relay_2 D2 
#define Relay_3 D3 
#define Relay_4 D4

digitalWrite(Relay_1, b ? HIGH : LOW);

void onRelay_1Change(boolean b){
  Serial.printf("onRelay_1Change: b: %d\n",b);
  digitalWrite(Relay_1,b ? HIGH : LOW);
}

void onRelay_2Change(boolean b){
  Serial.printf("onRelay_2Change: b: %d\n",b);
  digitalWrite(Relay_2,b ? HIGH : LOW);
}

void onRelay_3Change(boolean b){
  Serial.printf("onRelay_3Change: b: %d\n",b);
  digitalWrite(Relay_3,b ? HIGH : LOW);
}

void onRelay_4Change(boolean b){
  Serial.printf("onRelay_4Change: b: %d\n",b);
  digitalWrite(Relay_4,b ? HIGH : LOW);
}

pinMode(Relay_1, OUTPUT);
pinMode(Relay_2, OUTPUT);
pinMode(Relay_3, OUTPUT);
pinMode(Relay_4, OUTPUT);

digitalWrite(Relay_1, LOW);
digitalWrite(Relay_2, LOW);
digitalWrite(Relay_3, LOW);
digitalWrite(Relay_4, LOW);