I ran across this old Discovery Channel robotics documentary. It gives a very good rundown of the state-of-the-art in robotics in the late 90's.
Many of the ideas presented are now considered fundamental in robotics today. But you'll also see some flops and dead-ends.
What I find amusing are the lame hexapod robots repeatedly shown in the video were state-of-the-art in the 90's. Today, anyone can make make or buy one. Also, the 'bug' type analog robots which were really the result of inventors afraid of learning how to program. And I like how one guy said, paraphrased, 'it takes 3 weeks to build a robot but 2 man years to program it'. Today we can program a robot in hours.
https://www.youtube.com/watch?v=d3PHQP_bju0