Mobile Controlled Smart Home Automation

In this project the home appliances like Fan, Light, Motor, etc can be controlled easily with the help of smart mobile phones. In this project is very helpful to the old aged peoples.

ØArduino UNO X 1

Ø HC-05/HC-06 Bluetooth module X 1

Ø 5V relays X 4

Ø 1N4148 Diode X 4

Ø 1N4007 Diode X 2

Ø 1000uF Capcitor X 1

Ø IC7805 X 1

Ø 12V Transformer X 1

Ø PCB board X 1

Ø Jumper wires

Ø Lamp holder X 4

Ø Lamp X 4

Ø BC547 Transistor X 4

Ø 1K Resistor X 4

Ø Wire connector

This is two half-wave rectifiers combined - it uses a center-tapped secondary winding and one additional diode.Each side of the centre-tap has the same number of turns as our previous example - and each works for half the cycle as our half-wave rectifier did. The top half of the secondary works with one diode like the half-wave circuit we have just considered. When the polarity of the secondary changes, the upper diode shuts off and the lower diode conducts. The result is that the lower diode fills in another half-cycle in the waveform when the upper diode is not conducting.

The right relay depends on what you want to switch and how fast. What voltage, current, etc... You won't be able to drive it directly from the Arduino pin, as most general purpose relays require at least 150mW to switch which is >30mA @ 5V. You will need to use something like this:

The NPN can be just about any general purpose NPN (2N2222, BC337, etc) and the diode can be most general purpose diodes (1N4001 or similar) VCC is your +5V. If you go to somewhere like Farnell, and use the parametric search to narrow down you options, you will get hundreds of choices, here is an example search with 5VDC general purpose relays capable of >10A and >250VAC selected.

To use the HC05 module, simply connect the VCC to the 5V output on the Arduino, GND to Ground, RX to TX pin of the Arduino, and vice versa. [Editor's note: The RX pin is not officially 5 V tolerant; it is designed for 3.3 V signals. The Arduino generates a 5 V signal, so you should use a voltage divider or logic-level translator to ensure that the Arduino signal does not damage the HC05.] If you are using the BTBee module with the shield, set the jumpers on the board so that the DOUT pin and D0 pins are shorted and DIN and D1 pins are shorted. This is done because the RX pin on the Arduino is Pin 0 and the TX pin is Pin 1. You are free to use any other pins as the RX and TX Pins, but you will have to use the SoftwareSerial Library of the Arduino to enable that. Do remember to remove the jumpers while uploading code to the Arduino if you have selected Pin 0 and 1 as Serial pins.

Jumper connected to Pins 0 and 1 on the BTBee shield If the module is being used for the first time, you'll want to change the name, passcode etc. To do this the module should be set to command mode. Connect the Key pin to any pin on the Arduino and set it to high to allow the module to be programmed. If you're using the BTBee, it's a little tricky. While the official wiki says that the Mode Button must be held to change it to Command Mode, and releasing it changes it back to Data Mode, it doesn't happen that way: instead, hold the Mode button, then quickly press and release the Reset button. You will notice that the Status LED blinks slower than usual.