Autonomous Sentry Ideas

[3DWolf]

So I've got some ideas cookin in my head on how to recreate the Level 1 Sentry from Team Fortress 2 (airsoft version; non-lethal, don't worry), but I've come to a slight roadblock - the microprocessor.

I need one that's small enough to not destroy my wallet, but also powerful enough to be able to either use motion detector data or parse a camera signal and be able to read objects from it. I've seen some other platforms that use the latter method but they used a laptop next to the unit to do all the processing, but I want my unit to be enclosed within itself (aka no laptop).

Planning on using servos to move it, not quite sure which of those I'm going to need to use yet or not. Depending on the weight of the system I might have to use a high-torque one which I really hope I don't have to shell out the money for.

Anyone have any idea's or know of any good microprocessors that I can use for this? Preferably that support C or C++