guys i plan to make a surveillance robot... since my system is battery operated... power is a major constraint... therefore i am looking for dc motors for my robot which could provide me wid a decent rpm (150 to 300), decent torque to pull enough load and also not consume too much of the battery... I am open to any other ideas to keep my batteries alive... dude but i cant spend too much... so please suggest some viable option... a balanced trade off between power and cost... thanx in advance