This is taken from the movie Bill and Ted's Bogus journey. It refers to evil robot Ted and evil robot Bill seeing the photos of the princesess and Evil Ted getting a semi-erection and saying "I got a full-on robot chubby." Chubby being his penis before becoming turgid.
It has nothin to do with being turned on by robots. It is to do with ROBOTS being turned on!
Evil robot Ted: I got a full on robot chubby.
Evil robot Bill: Excellent! (Probably!)
A metal erection.
From Bill and teds bogus Journey
Woh ted, I've got a full-on robot chubby
When Darth Vader gets an erection.
In Star Wars Episode IV, you can see Darth Vader's Full-on Robot Chubby
Slang term used to describe the process of a male human being sexually aroused by a robot. Can be used with either male or female robots.
has a "full on robot chubby" for The Terminator.