i tried to control the speed of the line-following-robot (at the turnings)using pulse width modulation. but it did'nt work out well. actually, i am planning in such a way that the speed of the robot should decrease continuously from a certain distance b4 the turn ( for eg. it should keep on decreasing speed from 10 cm away from the turn) .can anybody suggest an idea for the speed control and the prediction of the turn ?????