[coreyjon]

Could you make a setup similar to a metal detector? On the front of your robot you could have a coil and send a pulsing current though it, when you get close to the steel, the induction of eddy currents can be detected using various methods, and you could set it up to go toward the source inducing the eddy currents..maybe. This is just an idea to help create others. I'm sure this can be done, just would take some experimenting. Good luck on your project.