How can I do this rig in Blender

[oo_1942 (Kim)]

Try Wigglebones Addon.
It seems possible to me.

old information

Wiggle bones (a jiggle bone implementation for 2.8)

NEW NOTICE: I have a new version 2 rewrite of the add-on announced here: Wiggle 2 Also, to minimize the need to hunt through this thread for various versions of this original addon i’ve tried to archive all the versions on github here: https://github.com/shteeve3d/blender-wiggle (that said I’m still learning github so the setup might still need some work) Thanks! ORIGINAL POST: Adding the latest current version to this first post. i need to properly set up a github or something so this is e…

New Wigglebones

Wiggle bones (a jiggle bone implementation for 2.8)

NEW NOTICE: I have a new version 2 rewrite of the add-on announced here: Wiggle 2 Also, to minimize the need to hunt through this thread for various versions of this original addon i’ve tried to archive all the versions on github here: https://github.com/shteeve3d/blender-wiggle (that said I’m still learning github so the setup might still need some work) Thanks! ORIGINAL POST: Adding the latest current version to this first post. i need to properly set up a github or something so this is e…

You can download it from the link above and there is a lot of information.
Try it and ask questions on the second link.