What is an "empty", and how do I tie armatures tog

I have been trying to learn how to do character animation. In the tutorials, I see the instruction to create an “empty,” but the tutorials seem to assume that I know what an “empty” is and what it is for. I don’t. What is an “empty” wrt an armature, and why is it used?

Second, I have created an armature for a human that consists of multiple small armatures combined into one object. This works for some movements, but for others it is impossible. For instance, I have one armature for the right arm, another for the left, another for the thoracic spine and another for the neck and head. When I move the arms, things work well. When I bend the back, however, the shoulders and head don’t move while the chest and back move as they should. Somehow I need to anchor the arms and head to the top of the spine. Unfortunately, I can’t seem to find a command to merge two armatures together so that when one moves, the other follows along. Is there a tutorial for this?



Well, an empty is an object, maybe even one that will help fix your problem. An empty has no substance, but you can treat it in many ways much as you would a mesh. To add an empty, hit the space bar>>add>>empty. You can parent this empty an armature, or to bones in your armature, and you can parent bone chains to the empty. another good use of empties is to set your characters eyes to track them. so wherever the empties go, thats where the character looks, but unlike a mesh, they never get in the way of the camera, or create unpleasant shadows. I hope this helps.
<edit> also, you can use empties as texture coordinates, by finding in materials, where it says ‘object’, filling in the name ‘Empty’, and then when you move the empty, you are changing the coordinates of the texture. You can also do this in the world buttons. to make your background animated.

Ah. I get the concept. Thanks. That was very helpful!

I also figured out the armature problem – I had created the various limbs but did not parent them to each other (like the fingers to the wrist in the hand tutorial).

Thank you very much for explaining empties to me. That made a lot of sense.