Driver on a Shape Key

In experimenting with Drivers (to try and learn them), I am trying to have the location of an Empty control the Shape Key of a Curve (which stretches the Curve out).

So, I have the Empty moving up and down on its z-axis. I then added a Driver for this Empty’s z-axis location (various values between 0 and 3 over sixty frames or so). I then did my best to arrange it so that the Curve’s Shape Key would copy these values (again, between 0 and 3).

However, I cannot get any response from the Curve’s Shape Keys. I don’t know whether this is another Bug (I previously filed a Bug Report on Drivers, and it was confirmed by or if I’m just doing things wrong. Below is a screencap of my set-up, followed by the .Blend.

Thanks and God bless, as always.


SoundwaveTest.blend (456 KB)

Something like this?

You had both keyed in the z location of the empty and were trying to drive it with the shape key? … also the controller object as a child of the curve as well as a bevel object was throwing a cyclic redundancy.


SoundwaveTest.blend (461 KB)

Thanks, batFINGER. I haven’t double-checked your solution yet, but I will soon and mark this as “Solved” as soon as I get it.

Ah…so I just had the Driver on the wrong Object! So I should have placed it on the Curve that needed to be controlled, not the Empty that was doing the controlling.

Thanks a lot, BatFinger!