Ok I know that it's not a new concept and this site is full of these things but since it was my first instructable I found that it was a pretty good project to start with as a beginner. The idea came to me as I was looking around to this website to be honest. I made it first on a breadboard and then I decided that I wanted to keep it permanent so here it is.
Part needed :
1. Arduino uno (or any other type of Arduino)
2. A wire cutter (to cut the wires and remove the plastic around them)
3. Soldering Iron
4. A protoboard (if you want to keep it permanent) or a small breadboard
5. An electric screwdriver
6. A buzzer
8. 7 resistors(6 220Ω for the leds and 1 for the buzzer, that depends from how many resistance your buzzer is going to have )
9. A HC-SR04 Ultrasonic distance sensor
10. Jumper wires
11. A 9v battery and a switch
12. A hobby box to put your finished project in
13.A piece of plexiglass
14. A lot of patience
Step 1: A few things to understand before we start!
Well this more easy than it sounds like. This tutorial helped me a lot to understand the mechanism so I totally recommend it to you!!
So basically what this Sensor does is to send an ultrasonic wave from the Trigger pin. This wave travels until it hits an obstacle. Then the Echo pin receives the returning wave and Sends this detail to the arduino. Then the arduino with a simple mathematical calculation it calculates the distance.So simple!!!