Make Biped Flex/Bounce Knees

Hey all, tried doing a search on the forum and came up with nothing, so here goes:

I’m trying to get my skeleton to be able to bend its knees when I move the upper body. Think kind of like a puppet bouncing up and down off the floor. When I translate ‘BRoot’ downwards (could be another bone nearby, I don’t care), I want the feet to stay in the same spot on the ground and the knees flex. Attached is the blend file. It seems like I’m missing something simple. Any ideas?

.blend attached, 2.49b.

P.S. Floor constraint also appears to not be working…?

Attachments

rolyskel.blend (229 KB)