Are you scared of thieves who can steal all your projects ??? :) :) Then this the perfect INSTRUCTABLE for you. This is an Anti-Theft alarm. When there is no thief around, then a blue LED will fade on and off; but if a thief tries to pass by the sensor, then suddenly red light will be seen and a loud police siren will be heard and it won't stop until the thief leaves the place; after leaving everything will be normal again.
This is a great project for starters and for science fairs; as it very cheap.
Best of luck...
Step 1: Gathering Components
1) Arduino Uno - 1 Piece
2) Mini Breadboard - 1 piece
3) red LED - 1 piece and blue LED - 1 piece
4) 330 ohm resistor - 2 piece
5) 100 ohm resistor - 1 piece and 10k resistor - 1 piece
6) TCRT5000 reflective sensor - 1 piece
7) Jumper wires
8) Piezo/Buzzer - 1 piece
Step 2: Connecting LEDs
Connect the LEDs as shown in the pictures.
Red LED: Connect the negative pin of LED (the shorter one) into the blue rail of breadboard. Connect the positive pin with one side of the 330 ohm resistor and connect another side of the resistor to Arduino digital pin 3.
Blue LED: Connect the negative pin of LED (the shorter one) into the blue rail of breadboard. Connect the positive pin with one side of the 330 ohm resistor and connect another side of the resistor to Arduino digital pin 5.
***Connect the resistor properly and tightly; Circuit doesn't work mostly for lose connection of resistor. I will tell about that later in this Instructables.
Step 3: Attaching the Buzzer
As shown in the picture, connect the positive pin of the buzzer (usually the longer one) to arduino digital pin 11. Connect the negative pin of the buzzer to the blue rail of the breadboard.
Step 4: Attaching the Sensor
There is a IR LED (the blue eye) and a IR Receiver (the black eye) in TCRT5000. Now, as shown in the pictures,hold the sensor so that the black eye is on the left and the blue eye is on the right. Now there are 2 pins just in front of you and another 2 pins are on the backside (far from you). The 2 pins just in front of you are the negative pins of the IR LED and Receiver.
Now, the 2 pins which are situated at the backside (far from you) are the positive pins of the IR LED and IR Receiver.
Connect the sensor as shown in the pictures.
Connect the 2 negative pins into the blue rail of the breadboard. Connect the positive pin of the IR LED (the blue eye) with one side of the 100 ohm resistor and connect another side of the resistor to the red rail of the breadboard.
Now, Connect the positive pin of the IR Receiver (the black eye) with one side of the 10k resistor and connect another side of the resistor to the red rail of the breadboard. Now, connect a wire from the positive pin of the IR Receiver to arduino Analog pin 0 (A0).
Cheque the pictures.
Step 5: Powering the Project
Connect the red rail of the breadboard to arduino 5v
Connect the Blue rail of the breadboard to arduino GND pin.
***Never make any mistake in this step.
Step 6: Must Read It
1) Check the resistor connections properly. If they are too lose, then curve the edges of the resistor and push into the breadboard tightly (As shown in the picture)
2) You should tie the wires together with tape. Nothing should be situated over the sensor. The frontal space of the sensor should be clear.
3) Sun rays contain IR . So, you must try this project where there is no sunlight; even you should not try this project beside window or doors; or it will give alarm without any thieves.
Step 7: Upload the Code
After all the steps, your project should look like the picture. You can extend the sensor with wires as long as possible. so you can set the sensor below your table or beside the door or anywhere.
Now download the ino file and upload it to arduino. Have Fun !!!
Watch the video for clearance.
If you like my project or if you have any question/suggestion/ problem...Just comment please.