Animating a chain with actions

Hi,
same thread here for those who speak german, but I didn’t get any answers there.

So, I try to animate tank tracks, but with the aid of the action editor.
I want to have 4 actions:

  • Move forward
  • Move backward
  • Turn left
  • Turn right

By adding a Curve in the time IPO I can decide whether the tracks are rotating or not and how fast they will go.

And now, my problem is how can I link the Time IPO to an action?