# OBSTACLE AND EDGE AVOIDING BOT

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## Introduction: OBSTACLE AND EDGE AVOIDING BOT

PARTS :

Ultra sonic sensor https://www.amazon.in/eHUB-HC-SR04-Ultrasonic-Det...

Jumper wires

motor driver (L293D) https://www.amazon.in/OLatus-OL-IC-L293D-Motor-Dri...

VIDEO

### Teacher Notes

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## Step 1: CONNECTING THE STUFF

CIRCUIT CONNECTION ;

The circuit connections are shown in the above figure

## Step 2: WORKING OF EACH SENSOR

ULTRA SONIC SENSOR : As shown above the HC-SR04 Ultrasonic (US) sensor is a 4 pin module, whose pin names are Vcc, Trigger, Echo and Ground respectively. This sensor is a very popular sensor used in many applications where measuring distance or sensing objects are required. The module has two eyes like projects in the front which forms the Ultrasonic transmitter and Receiver. The sensor works with the simple high school formula that Distance = Speed × Time The Ultrasonic transmitter transmits an ultrasonic wave, this wave travels in air and when it gets objected by any material it gets reflected back toward the sensor this reflected wave is observed by the Ultrasonic receiver module as shown in the picture below Now, to calculate the distance using the above formulae, we should know the Speed and time. Since we are using the Ultrasonic wave we know the universal speed of US wave at room conditions which is 330m/s. The circuitry inbuilt on the module will calculate the time taken for the US wave to come back and turns on the echo pin high for that same particular amount of time, this way we can also know the time taken. Now simply calculate the distance using a microcontroller or microprocessor.

WORKING OF IR Sensor: An infrared sensor is an electronic device, that emits in order to sense some aspects of the surroundings. An IR sensor can measure the heat of an object as well as detects the motion. These types of sensors measure only infrared radiation, rather than emitting it that is called a passive IR sensor. Usually, in the infrared spectrum, all the objects radiate some form of thermal radiation. These types of radiations are invisible to our eyes, that can be detected by an infrared sensor. The emitter is simply an IR LED (Light Emitting Diode) and the detector is simply an IR photodiode that is sensitive to IR light of the same wavelength as that emitted by the IR LED. When IR light falls on the photodiode, the resistances and the output voltages will change in proportion to the magnitude of the IR light received.

## Step 3: WORKING ON THE CODE

In the following code you might require to change the connections of the dc motor and try connecting it with

different ways .

if your are getting any doubt about working of the ultra sonic sensor you can try looking into the

following video

.i referenced the same video when I got to learn about the stuff i hope this will help u out

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