Introduction to combinatorics

- Hi, my name is Lou Hamou-Lhadj. I'm a Character TD here at Pixar. - Hi, I'm Jacob Speirs, I'm also a Character TD at Pixar. - [Lou] We started here at Pixar on WALL-E as interns and our task was to make a huge cast of background robots. - Today's lesson is going to be about how to create a huge crowd of robots using only a few simple parts. (mechanical clicks) - I wanna take WALL-E from a world where there's no robots anymore and it's just him to a world where there's tons of them. I just like that contrast and suddenly making him feel like he was alone in a crowd. - We're trying to create a world where robots do every task that you would want done. What we did first was to look at cruise ships. We got a list of every single job on a cruise ship and then went through and tried to think of the robotic equivalent of that job and it became apparent quickly that that was more robots than we would ever be able to build in one lifetime. - So as interns, Jacob and I had the task of making this huge cast of robots, but we didn't want to design each individual one specifically. - Right, so luckily there was an animator, Angus, and he had a great idea about how to approach the process. - I'm a huge Lego fan and I really wanted the background characters to be the best they could be and I figured if we designed a modular system that would allow for us to add and subtract different parts onto the character for the background characters then we could kinda make whatever we needed and it would all feel like the same world. - [Lou] Doing it this way, modularly, meant we could build 10 heads, 10 arms, and 10 bodies and though we'd only built 30 pieces we could make a thousand different combinations. - Yeah, and there's actually a branch of mathematics about that sort of thing, counting and combinations and it's called combinatorics. (mechanical noises) - Combinatorics is actually what your lesson today is gonna be about. We're gonna start with a few small pieces and build a huge cast of robots just like we did.