Brickset identifies JØRN THOMSEN as the designer of the 31313 set:
Although I'm also inclined to believe that probably a group of people came up with the various initial robots.
I think that actually the five main robots were made by a group of people.
On this page, it tells who designed the fan robots, but it doesn't say so for the 5 main robots, which include EV3RSTORM.
To quote from this site:
Like the early robot turtles, these programmable Lego constructions were still tethered to a computer with wires. So Seymour Papert ...
To be fair, it is hard to tell and depending on definition you may even tell TLG has never stopped doing so. But it depends on the series.
Bricklink has a lot of catalogs in their item data base. Single leaflet catalogs are called "Mini" and small booklet ones are called "Medium". Catalogs you can find in store are called "Large"...