Outside Henson projects, Robertson played the title character on Zoboomafoo and worked with Shari Lewis on Lamb Chop's Play Along (as Buster the Bus) and The Charlie Horse Music Pizza (as Fingers the raccoon). He played Galileo on Groundling Marsh and Bill the ventriloquist dummy on the sitcom Puppets Who Kill. In film, he was chief puppeteer on the non-Henson Teenage Mutant Ninja Turtles III (also face puppeteer for Michaelangelo), one of the puppeteers for Johnny 5 in Short Circuit 2, and worked on Mr. Magorium's Wonder Emporium.
- Fraggle Rock: Pa Gorg (body), Inkspots, Rumple Fraggle, Tumbrell Doozer
- The Fantastic Miss Piggy Show: Additional Muppet Performer (uncredited)
- The Muppets: A Celebration of 30 Years: Additional Muppet Performer (uncredited)
- Follow That Bird: Daddy Dodo (body)
- Sesame Park: Dodi (assistant), others
- The Jim Henson Hour: Chip, Lindbergh, Polar Bear (Lighthouse Island), Scruffy (Dog City)
- Teenage Mutant Ninja Turtles II: The Secret of the Ooze: Rahzar (face puppeteer)
- Basil Hears a Noise
- The Neverending Story III: Falkor (puppeteer)
- Brats of the Lost Nebula
- Cats & Dogs
- It's a Very Merry Muppet Christmas Movie: Additional Muppet Performer
- The Muppets' Wizard of Oz: Additional Muppet Performer
- Turkey Hollow: Thrinng
- Puppets Who Kill official site. Cast bios.
- Presskit bio. Kratt Club fan page (archived).