September 06, 2018 by Reginald Watson
Take your Android smartwatch to the next level by connecting it to a 5V relay with an Arduino over Bluetooth.
Do you want to use your smartwatch to control things around you? This can be done very easily within a few hours! In this tutorial, I will show you how to control your home appliances with an Android Wear watch. I’ll be using the Moto360 watch, but you can install the app in any Wear OS (formerly Android Wear) watch. At the end of this project, you will be able to control any electrical device with the flick of your wrist.
Arduino UNO
5V relay
HC-06 Bluetooth module
Any Wear OS watch (I'll be using my Moto360 watch for this tutorial)
Connect the hardware as shown in the schematics below.
Connect your Arduino UNO to the HC-06 Bluetooth module.
Please be careful with this step! Remove the electric supply first. This will work as a switch, so remove the physical switch and connect to relay pin NC and COM and tighten the screw.
You can install Arduino IDE by on Arduino's website.
Once installed, open Arduino IDE and connect your Arduino UNO with a USB cable.
This code uses Arduino’s serial communication protocol with the Bluetooth module. The RX and TX pins of the Arduino connect to the TX and RX pins of the HC-06 Bluetooth module, respectively.
The Bluetooth module receives data from the paired Android smartwatch and triggers the relay based on the received data.
The code behind this is pretty simple. If the received data is the character "1", the relay will be triggered and turned on, and if the received data is the character "0", the relay will be turned off.
//--------BT app control---------//
//Program for four switches but in our case we are using pin 11
int switch1=11;
int switch2=12;
int switch3=8;
int switch4=7;
int Received=0;
int switch1_state =0;
int switch2_state =0;
int switch3_state = 0;
int switch4_state = 0;
void setup(){
Serial.begin(9600);
pinMode(switch1,OUTPUT);
pinMode(switch2,OUTPUT);
pinMode(switch3,OUTPUT);
pinMode(switch4,OUTPUT);
}
void loop(){
if(Serial.available()>0)
{
Received = Serial.read();
}
////////////////switch1/////////////////////
if (switch1_state == 0 && Received == '1')
{
digitalWrite(switch1,HIGH);
switch1_state=1;
Received=0;
}
if (switch1_state ==1 && Received == '1')
{
digitalWrite(switch1,LOW);
switch1_state=0;
Received=0;
}
////////////////switch2/////////////////////
if (switch2_state == 0 && Received == '2')
{
digitalWrite(switch2,HIGH);
switch2_state=1;
Received=0;
}
if (switch2_state ==1 && Received == '2')
{
digitalWrite(switch2,LOW);
switch2_state=0;
Received=0;
}
///////////////////////////////////////////
////////////////switch3/////////////////////
if (switch3_state == 0 && Received == '3')
{
digitalWrite(switch3,HIGH);
switch3_state=1;
Received=0;
}
if (switch3_state ==1 && Received == '3')
{
digitalWrite(switch3,LOW);
switch3_state=0;
Received=0;
}
///////////////////////////////////////////
////////////////switch4/////////////////////
if (switch4_state == 0 && Received == '4')
{
digitalWrite(switch4,HIGH);
switch4_state=1;
Received=0;
}
if (switch4_state ==1 && Received == '4')
{
digitalWrite(switch4,LOW);
switch4_state=0;
Received=0;
}
}Download the apk file for the smartwatch app.
Using ADB over Wi-Fi, follow these steps to install the app on your smartwatch:
The menu you need to access in the second step listed above.
How the commands will look after proper installation of the app.
After installation, connect your smartwatch to the HC-06 module.
You need to pair the HC-06 Bluetooth module with your Android smartwatch before you can use it in the app.
You should see the HC-06 device available on your smartwatch.
Now follow these steps:
And that's it! Your smartwatch is now connected. You can now control the 5V relay through your watch via Bluetooth.
To watch the project take shape from start to finish, watch the video below.
I love challenging myself by creating new projects using different microcontrollers to see what I can come up with.
