Warframes were basically non-sentient robots, built to be powered, and operated, by void-touched children through their psychic powers. The children have since grown up, they still have their powers and the Warframes are still under their control. However, in the game, there are times when the Warframes exhibit behaviours that would require them to be controlled, while they are not being controlled...What that says about them, I don't know - or maybe I misunderstood something while I played...