Ultron Series Robot Guards

UltronUltron was created by Tony Stark and Hank Pym.  Using Hank Pym's brain waves as a basis for the Ultron AI, the series was built with non-lethal weaponry and incapable of taking aggressive action.  SHIELD used the Ultron series of robots to act as guards in the super-prison "The Big House", and then later in the super-prison "42".

During the invasion of Earth by Kang the Conquerer, Hank Pym changed their programming algorhythm, turning them into soldiers capable of attacking Kang's invasion force.  All except Ultron-5 were destroyed during that conflict.