Vision based obstacle avoider

Folks! It is just not another project where the robot walks autonomously avoiding obstacles in its path. This robot is a vision based obstacle avoider. It uses a camera to detect obstacles in its path and also operates wirelessly. The wireless vision bases obstacle avoider is a sincere effort from Ashish Derhgewan; an electronics student at IISC Bangalore (Mobile Robotics Lab).

The project has two standalone units; a RF transmitter and a RF receiver which operates at a frequency of 315MHz. IC HT12E (parallel to serial encoder) and IC HT12D (serial to parallel decoder) is used to connect these RF modules to the computer. The HT12E is a 12 bit parallel to serial encoder. Of those 12 bits, 8 bits are the address code, and the remaining 4 bits are data. To send a signal, the address bits on the transmitter and receiver should be the same. Just like setting a password! The transmitter unit involves a wireless camera that transmits video signals to a nearby “big” computer. This big computer runs all the computer vision codes, identifies the obstacles using image processing toolbox, and then somehow tells the robot how to avoid them. This is where wireless communication comes in.

Another interesting point to learn here is how the interference of noise signals is avoided in the functioning of the robot. Well, the noise signals can creep into the receiver only when the address bits on the decoder matches to those of the noisy data. Also, avoid using an AC to DC adapter for power supply because this introduces radio interference noise into your decoder. So, opting batteries to supply power to your robot is a far better option.

The Arduino brain is used to control the robot which directly interacts with the computer through a USB to serial cable. The Arduino is controlled in software. Here, the designer has used C# application to send commands to Arduino.