Bluetooth Controlled Light Switch

Don't stumble around looking for the light switch, turn it on before you walk inside using a bluetooth-enabled android phone!

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Things used in this project

Hardware components

Texas Instruments Dual H-Bridge motor drivers L293D

Servos (Tower Pro MG996R)

Hitec HS-311 modified to DC

HC-05 Bluetooth Module

Arduino UNO

Jumper wires (generic)

Breadboard (generic)

Mounting Hardware

Screws, drywall anchors, zip ties, aluminum sheet metal, rubber bands

Android device

Software apps and online services

BlueTerm

android app

Hand tools and fabrication machines

Drill Press

Used the one in the Junior Design Lab, brought my own bits

Story

Do you get home from work after dark? Are you tired of stumbling around looking for your poorly-placed light switch? Are you just too lazy to get out of bed and turn the lights off before you go to sleep? We've built a Bluetooth based project that signals an Arduino to power a DC motor to flick your light switch off or on. All you have to do is bolt it to the wall next to almost any switch, and control it with your android phone!

Switch Flicker mounted in my bedroom.

When you connect to the device via any Arduino Bluetooth app, you send signals to the controller using your phones keypad. Sending a number 1 flicks the lights on, and sending a number 2 flicks them off. The 180 degree servo used is a hitec-311 gear motor. We converted the motor to DC for ease of directional control with the stepper motor driver.

Demo Video

Code

Arduino Bluetooth Motor controller code

int motorPin1 = 3; // pin 2 on L293D 
int motorPin2 = 4; // pin 7 on L293D 
int enablePin = 5; // pin 1 on L293D 
int state;
int flag=0;        //makes sure that the serial only prints once the state

void setup() {
    // sets the pins as outputs:
    pinMode(motorPin1, OUTPUT);
    pinMode(motorPin2, OUTPUT);
    pinMode(enablePin, OUTPUT);
    // sets enablePin high so that motor can turn on:
    digitalWrite(enablePin, HIGH);

    Serial.begin(9600);
}

void loop() {
    //if some date is sent, reads it and saves in state
    if(Serial.available() > 0){     
      state = Serial.read();   
      flag=0;
    }   
    // if the state is '0' the DC motor will turn off
    if (state == '0') {
        digitalWrite(motorPin1, LOW); // set pin 2 on L293D low
        digitalWrite(motorPin2, LOW); // set pin 7 on L293D low
        if(flag == 0){
          Serial.println("Motor: off");
          flag=1;
        }
    }
    // if the state is '1' the motor will turn right
    else if (state == '1') {
        digitalWrite(motorPin1, LOW); // set pin 2 on L293D low
        digitalWrite(motorPin2, HIGH); // set pin 7 on L293D high
        if(flag == 0){
          Serial.println("Motor: right");
          flag=1;
        }
    }
    // if the state is '2' the motor will turn left
    else if (state == '2') {
        digitalWrite(motorPin1, HIGH); // set pin 2 on L293D high
        digitalWrite(motorPin2, LOW); // set pin 7 on L293D low
        if(flag == 0){
          Serial.println("Motor: left");
          flag=1;
        }
    }
}

Bluetooth Controlled Light Switch