1978 Survival Research Laboratories performance art often involving destroying robots creatively (for perspective, Beyond Thunderdome came out in 1985)
1987 Critter Crunch was sponsored by the Denver Mad Scientist Society (quirky rules prevented it from taking off, but these are my kind of people)
1989 Project FIRST (For Inspiration and Recognition of Science and Technology) This was how I first learned of Dean Kamen ( The Segway guy, and top of my list)
1993 BEST robotics
1997 Robot Wars the tv show from England without consent from Marc Thorpe
(here there was a giant explosion of multiple robotics competitions from middle school, to college, no doubt inspired by the tv show, I know I loved it.)
1998 FIRST lego league
1999 Battlebots by the people who once worked with Marc Thorpe.
Each image links to a video.