Need help understanding IK bones and pole bones


(Joe Smith) #1

I am not too sure in the IK bone what is a target and what is a pole target? And what do you need to make that leg bone an IK bone?


(insolitus) #2

There are loads of youtube tutorials on this, search and you will find. :wink:
But for a quick answer, the bone pointing out backwards from the heel is the target and the bone in front of the knee that is not connected to the rest of the leg, is the pole target.


(Joe Smith) #3

Sure there are plenty of YouTube tutorials that shows how to do this, but they don’t do a good job at explaining why we need to do this and that.

So what is the target exactly?

ANd what is a pole target what does it exactly do?


(insolitus) #4

Ah, then I understand what you need! I’ll see if I can find a good tutorial for that later today, unless someone already explained it by then.


(Joe Smith) #5

Thanks bro :slight_smile:


(insolitus) #6

Ok check this out Joe! https://www.youtube.com/playlist?list=PL3wFcRXImVPOQpi-wi7uriXBkykXVUntv
I recommend watching everything because it’s really good, but in your case, at least part 5 to 8 would be helpful. Ask away if you have any questions that are not answered in the videos. :beers:


(Joe Smith) #7

Thanks bro so much :slight_smile:


(Joe Smith) #8

Hey man,

I understand what does Pole Target and Target do, but I don’t fully understand IK bones. Are IK bones supposed to be controlled by another bone by the Target?


(insolitus) #9

Hey! So Target and Pole Target is clear? Good! :+1:
I’m not totally sure I understand your question though. I’ll try to explain what I think you ask.
In the simplest form an IK chain consists of a number of connected bones, something like this:

Root-Bone0-Bone1-BoneTarget

Where Bone0 and BoneTarget is parented to Root and Bone1 is parented to Bone0. Bone1 is given the IK bone constraint. In the constraint the target is set to BoneTarget and Chain Length set to 2 so that Root isn’t affected.
BoneTarget is parented to Root so it can be moved with the rig if needed.
In some rigs BoneTarget is better parented to another bone in the rig, and some times BoneTarget is easier animated as it is. This totally depends on the need and complexity of the rig and nothing that can be said generally. At least not to my knowledge.

Does this help you? Otherwise it’s probably better if you show an actual example to discuss! :slight_smile:


(Joe Smith) #10

Since Bone1 is given the IK constraint and the target is the BoneTarget, that means that moving the BoneTarget around would cause Bone1 to move and Bone0 since we set the chainlength to 2, am I understanding this correctly?

Thanks for explaining it for me =D


(insolitus) #11

Yes, that is correct! :smiley:
No problem, glad to be of help! :+1:


(FinalBarrage) #12

Im aware that its already been solved, but i’ve moved it to #support:animation-and-rigging.


(Joe Smith) #13

Thanks bro :slight_smile:


(Joe Smith) #14

I should have posted this post under that heading.