It's Leo G Clark, inventor, owner and operator of Truckasaurus!
He's so specifically named, and even designed, that I thought maybe he could be a reference to an existing person. Robosaurus's inventor was Douglas Malewicki (and he doesn't look like this guy), and the only Leo G Clark I found was an elevator operator in New York (I suspect this is coincidence.) If you have any further insight into the origin of this very specific character, comment below! Or keep it a secret if you like, I'll never know!
This post is part of my "Every Simpsons Character Ever" series. For a list of my rules in this project, click here.