I've looked at a couple of circuits that I=B4m considering to use in my SUMO-bot. The purpose of the circuit is to detect a white line at the edge of the SUMO-ring and use this detection to steer away from it.
My bot will have two powered wheels, 1 motor per wheel. I=B4m thinking of using one detetctor at each front corner (my bot will only drive forward and turn so rear detetction will be unnesesary). I figure that if I hook it up in such a way that it will cut the power to the engine on the opposite side it will do the trick.
But when I look at possible solutions I find that some use LDR=B4s (Light Dependant Resistors) and some use phototransistors. I have trouble finding any LDR=B4s to buy and by the info I=B4ve seen (not very much I=B4m afraid) about phototransistors they seem to be the better choise, but can I use them as a substitute for LDR=B4s or do they have fundemantal difrences?
Would I have to use them in pair with LED=B4s to get enough light? (the detectors will be mounted under the robot, so its possible that not much light will get in)
Can anyone think of a circuit that might help me do the thing I want? (a www-reference would be lovely, I can't seem to find just the thing on the web and my electronics books are from the 70=B4s so quite a lot of the components are outdated)
Thanks! /David