Hi, I'm building an battle robot. The total weight of the bot is round 40KG. I want to implement an steering mechanism for my bot. For that i found Rack and pinion arrangement. But the problem in that is, how to make an DC motor to rotate just for a few revolutions? Another method which can be used is an servo steering mechanism. But since most hobby servos are made out of nylon gears, i don't know whether they will be able to handle the stress? Is there any schematic diagram for an steering arrangement using an servo motor? Thanks!