"Outmode" is a term frequently used in Robots. It is used to describe a robot with parts that are no longer produced, who also cannot afford to purchase upgrades for him or herself.
"Outmodes" are robots with older models, who have worn out or broken parts, and with parts that are no longer produced. Prior to the movie, Ratchet has taken over Bigweld Industries. He forces the company to stop making spare parts, leaving only one option for robots everywhere: to purchase upgrades for themselves. Those who cannot afford upgrades and/or even refuse to get upgrades are considered "outmodes", as they can no longer repair themselves and will eventually break down. At this point, they will be sucked up by sweepers and taken to the Chop Shop. However, the outmodes are spared from this fate after Rodney arrives in Robot City and begins to repair them himself and also bringing the end to Ratchet and Madame Gasket's reign of terror, fascism and conformity throughout the entire city.
The Rusties are a ragtag band of outmodes who live at Aunt Fanny's boarding house. They are the first friendly faces Rodney meets when he comes to Robot City, and despite getting off on the wrong foot with him, they become his best friends and loyal allies as the movie progresses:
- Herb Copperbottom: After Bigweld Industries ceases the production of spare parts, it is mentioned that Herb is beginning to break down and is in need of new parts, meaning he can technically be classified as an outmode. However, he is no longer one, because he gets repaired by the end of the movie, thanks to Bigweld.
- Madame Gasket: Although she is the mastermind behind the plan to eliminate all outmodes, her appearance suggests that she herself is an outmode. This is never explained or elaborated on, and it is unknown what Madame Gasket has against outmodes. Also why she never got an upgrade herself since she hates outmodes and she and her son, Ratchet forcing about every robots to get upgrades or get eliminated.
- Jack Hammer: Like Madame Gasket, his appearance suggests that he too is an outmode. However, given that all his parts seem to be working and he doesn't seem to be in any financial trouble, this could be false. It is unknown if he is an outmode or not.
- It's possible that "outmodes" is actually a slur in the Robots universe, this is evident when Ratchet referred to them as "scrap metal" as a sign of superiority to anyone without upgrades.