I'm in the process if building my first robot......although (according to a friend of mine in another forum), its more of a 'finite state machine' than a full blown AI. I normally would have posted something like this in the computer science thread, but Intelligence and machines is a closer match IMO. Basic synopsis - this is a quazi-robotic car. It will accept directional tasks and perform them governed by sensor data and pre-programmed criteria. The first (and only) problem I'm having trouble wrapping my head around is how to accurately establish position in real-space. My machine does not come with any sensors that empirically tell it how far its traveled. For example - I can't really tell it to "travel 10 feet forward - 3 feet left" without this. I can improvise using time multiplied by speed or something like that, but I want something more solid. I can add sensors if need be (if you guys have any suggestions on what exactly, let me know) - albeit limited to anything that's inexpensive and small enough to fit on a 1/10 scale R/C car. GPS is an option - although I *think* commercial GPS doesn't resolve down to a certain distance, and may have issues with lag-time or connectivity (useless inside a building). The easiest solution I can think of so far is a webcam and ping-pong balls. I can paint them all bright identifiable colors, and associate them with nodes on a pre-defined map. This limits me to pre-defined maps though (I can't take it to the tennis court down the street without setting up more ping pong balls and manually writing a new map) let me know if you have any input on this.