Question: Using 1 bone for driven shape keys

Support Animation and Rigging
1

Is it not possible to use 1 bone to drive two shape keys dependant on the translation of one axis?

I want to drive 1 shape key when in + Y

and drive the other shape key when the bone is in the -Y translation

Is this possible?

So far I can’t seem to get it to work.

2

Hi TA,

A little confused as to what you are asking … if you want zero influence to the other when the in +Y and vice versa then using the method outlined here http://aligorith.blogspot.com/2011/01/rigging-faq-addedum-info-on-drivers.html should do the trick by setting up drivers on each shape key and checking the translation in a script and returning the translation if in the pos/neg or zero otherwise.

3

Yes it’s possible, it’s just a matter of setting it up that way. Take a look at the attached .blend file for 2.56a. In it there is a bone and 2 shape keys on a cube, rotate the bone to the left, and the left shape key works, rotate the bone to the right, the right shape key works.

2shapes1bone.blend (434 KB)

Randy

Oh, I know this isn’t what you are asking about, but I did a video tutorial where I get one shape key to work if the bone is moved to the left, or right, and when the bone is in the middle the shape key is off. See here:

4

WTF? LOL

I tried earlier today with my blend file before posting, what you did in your blend file. I swear I did anyways. Using a positive amount in the first driver and a negative in the other. Never worked.

I load up your file though and it works. And then I try it again in mine and it works!

MAGIC!!!

Obviously I really goofed up on the wiring somewhere.

Thanks Randy its working perfectly now. His head stretches with the bone going up and than it squashes when the bone goes down.

Cheers Dude!

Thanks for your help to batFINGER. I’ll have a look.