This instructable tutorial is about "How To Build An Arduino Obstacle Avoiding Robot".Youtube video that I've uploaded recently. I strongly recommend you to check it out. Let's get started !

Step 1: A Chassis!

In first step,construct chassis by using 3-D printer or buy from any online electronics website.I got mine from instock.pk and i'll also mention link below.You can also make your own chassis by cardboard and DC/Servo motor.Chassis comprises body,two motors,battery holder,bread board and switch.

Step 2: Component Description

We will use the Arduino uno board and an ultrasonic sensor. If the robot detects an object infront of it, with the help of a small servo motor, it scans the area left and right in order to find the best way to turn.

For this project you will need:

Arduino UNO

Mini breadboard

L298N motor driver module with 2x dc motors with wheels

HC-SR04 ultrasonic sensor

Micro servo motor

9V battery holder (with power jack)

10 jumper wires

10 nuts and 10 screws

Step 3: Circuit Diagram by Using Fritzing

Step 4: Construction

Use the screws, and nuts to attach the Arduino uno board and the L298N module on chassis. The mini breadboard can be easily attached on it with the glue.
Attach the tiny servo motor infront side of robot and place ultrasonic sensor on it.

Step 5: Code by Using ArduBlock

Step 6: Completed!

Now you have your own Arduino Obstacle Avoiding Robot!!!

Step 7: Note

As the project is based on Arduino, the programming is very easy and can be easily modified.
Doesn’t require the Arduino Motor Shield.
When using a 9V battery, at least 2 such batteries are needed to power the robot. It is better to use 2 9V batteries (one for Arduino, Ultrasonic sensor, Servo Motor and the other one for L293D and motors).
The Ultrasonic sensor should not be connected directly to power supply as it might affect the normal performance.