Smart Voice Controller (Arduino) - Android Smartphone

Introduction: Smart Voice Controller (Arduino) - Android Smartphone

Smart Voice Controller is a device that is extremely practical, interesting and easy to make. Through it you can control up to 8 devices in your home, by voice commands from your smartphone. You only need your phone to work with Android, has Bluetooth and internet.

Step 1: Software for Smartphones With ANDROID:

The software converts your voice commands and sends them to the controller. For this conversion need to have Internet connectivity on your phone. Commands wich will controll each individual relay output (or multiple outputs), must be predefined and stored in the controller below. ie each relay should know what command will change it's state.


relay 1 (ON) - Voice COMMAND: light on

relay 1 (OFF) - Voice COMMAND: light off

relay 2 (ON) - Voice COMMAND: fan on

relay 2 (OFF) - Voice COMMAND: fan off


Command for relay response is pre-set in the Arduino controller software which we describe below in the article. To download the software for Android, visit section Software for Android in the Author's website.

Step 2: Controller (with 8 Relay Outputs):

To make the controller there is no need to have skills in making circuit boards. The controller is constructed of 3 modules which are sold at electronics stores. You only need to connect them as described. Even if they are not available in local stores in your town, all devices can be ordered online.

Arduino UNO - Look at

JY-MCU Bluetooth module - this is serial bluetooth module but placed on board to work with 5 volts. Can be used only HC-05 or HC-06 if you do not find JY-MCU but remember to lower the voltage to 3.3 volts. JY-MCU can buy from

8 Channel 12V or 5V module for Arduino - it is recomĐżended to use a 12 volt model of the shield, although the 5 volt are most used. If triggered 8 realys with 5 volts supply taken from Arduino voltage regulator has risk to preheat the regultor. For this reason we use 12 volt version and take the power directly before build-in voltage regulator in Arduino. You can find shield in

12V power supply - can be purchased from any eletronics store.

Step 3: Controller Software (for Arduino):

The code of SVC_Arduino.ino is attached article in the authors website. Click below to view the source code .The code must be loaded into the Arduino to be able to respond to your voice commands. With red colored lines is marked the code where you can change it to use your custom voice commands. You can also add process like allon() in the code, to trigger only a couple of relays simultaneously with one command, instead of all (as is done with the voice command all on/off below in the code).The schematic can be set to react in different languages. Once you upload the code to the Arduino, the schematic does not require computer to work.


When programming the Arduino. disconnect TX and RX pin from the Bluetooth module because it can cause a conflict in communication and may not be able to upload the software.

Step 4: Download:

Source code - Archive contains only the source code for Arduino.

Arduino and source code - Archive contains Arduino software including source code of the controller.

The password for all archives article:

Step 5: Additional Information About the Bluetooth Module:

Bluetooth module operates normally with its default settings. Default password for bluetooth module is 1234. If you decide to have more control in the options of the module i suggest you read the following article. In in you will find information: How to change the name of the bluetooth, password entry or speed of data transfer. Good luck with your experiments.




You can view more interesting schematics in

Step 6: Pictures:



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    11 Discussions

    hi kukata86,

    This project is absolutely beautiful. I tried the same with exact hardware and programming. I used HC 05 bluetooth module. Somehow, the relays go in high trigger mode and does not come de energized with voice commands at all. Can you help with relays problem !!! I am using 5 V relay and tried all ways of connections. ex. 5v from aurduino, external 5v supply, JdVcc and so on but no luck. can you please help why the relays are not triggering back with voice command???

    hai sir I am Rithun and i am studying for B Tech.So I would like to do this as my mini project.but I don't know exactly about the programe and how to implement on the Arduino board. so will you please help me?

    hai sir I am Rithun and i am studying for B Tech.So I would like to do this as my mini project.but I don't know exactly about the programe and how to implement on the Arduino board. so will you please help me?

    Hi, very nice project! is it possible to mae it run on wifi or network instead of bluetooth?

    sometimes get malfunction
    things go autonomous by itself

    1 reply

    i not have this problem,it's powered 24 hours a day

    Are you sure?

    can i knw why the Vin pin is connected to 12v on relay board whats it function and why you used 7805 in 5 v relay board

    1 reply

    Vin is arduino pin that have the same voltage like supply of Arduino. If you use 12 volts , Vin has 12 volts,
    The relay boards are 2 types, with 12V and with 5V power supply, I use 5 V version and need 5 Volts supply, and use 7805. If you use 12V version 7805 is not nessesary.
    BTW. dont use from 5 volt pin from arduino to supply the relays becouse can burn stabiliser in arduino board.better use external 7805 like me.
    I hope this help.

    Looks pretty handy....I'd probably use them to shut off power to vampire loads....things like chargers that don't need to be getting juice all of the time...