This was our first major Line Follower robot. The event was held in Anna University(CEG), Chennai back in 2008. The problem statement was : Design and Build a robot which can follow a black line on a white background. The arena would have lots of turns, including sharp ones (less than 90°). It would also have breaks and multipaths. The robot has to make decisions and traverse the entire path.
The code was entirely written using C in the CodeVision AVR Compiler which is by far the most versatile one I have ever seen. It has a lot of inbuilt modules and functions which can be used. The Microcontroller used was Atmel AVR ATmega8. We also used a lot of logic circuitry to boost the speed and control of the bot. It helps a lot when you are have stiff competition and your peers are as stong as you. Apart from a good code, one needs to look into the mechanical aspects of the robot design. The placement of the sensors and motors play a crucial role in the efficient functioning of the bot. In an arena like the one shown above, there are loads of twists and turns which predominantly makes the bot go mad. So, always make sure you get the design right!
As i said earlier, the most essential part in building a perfect line follower robot is to make sure the sensor arrangement is top notch. We tried a series of arrangements before we finalized to the 6 sensor one. 2 on the outer edges of the line and 4 kept symmetrically outside the line. This type of arrangement makes sure the bot is always kept close to the line(while following) as possible, and also to make perfect turns and not to shoot out of the line.Here is a video of the robot in action. I shall try to find the source code of this project and upload it here.
