I've set up a piston-type of arrangement following a tutorial on YouTube, but now want to expand on it a little. I have added a bone that moves upwards as the piston moves through it's motion, but would like to lock the tail of the bone in place so that it doesn't move (see the diagram below). At the moment the whole bone moves upwards as it is parented to a bone in the middle of the piston IK setup. All I need to do is lock the tail from moving at all.
How might I go about this?