Simple Line Following Robot using Transistors

Circuit Diagram and more information on the link below
http://rookieelectronics.com/lfr-using-transistors/

Yes. It uses just transistors, Simplest, Cheapest and easiest Line Following Robot ever!!!
It uses BC108 Trnasistors

To see step by step procedure to make one circuit like this, hit the link below

This LFR uses differential drive method, as you can see it moves with little jerks, If you want one smooth and more efficient PWM(oulse width modulation) based line following Robot circuit made on three 555 timers hit on the link below
http://www.youtube.com/watch?v=NxVviQp0J5c

Duration : 0:1:23