Joints Wont Bend After IK Handle Attached

[Anonymous]

Hey,

I’m very new to rigging, it’s been going well so far but now I’ve hit a bit of a wall.

I’ve imported the First Person Skeletal Rig from UE4 and want to set up some IK Handles to the arms so I can get an IK/FK Switch going. I’ve got some control curves for the arms, wrist and fingers but whenever I attach an IK Handle from the shoulder to the wrist, the arm rig stiffs up and when I move the handle the arm doesn’t bend. Any ideas? I feel like I may have made a rookie mistake somewhere. Hope someone can help.

[Anonymous]

It's hard to diagnose from just these three images. Did you by chance do a single-chain IK handle? When you use the IK handle tool to make the IK, go into it's tool settings and make sure you're making a rotate-plane IK handle.

Other than that, I don't have any ideas from the info you provided. You're probably going to need to post a scene file or something if this doesn't solve it so we can actually look at everything. Good luck!

[Anonymous]

Hey, thanks for replying.

I made sure that I was using an RP IK Handle yeah, I'm also sure I used a single chain too. You're more than welcome to have a look at the scene file I've attached, I would certainly appreicate it. As I stated before I'm very new to rigging.

[Anonymous · Accepted solution]

Alright, here's the issues I found:

• There's keys on all your joints, they aren't moving them, but they are creating an incoming connection that has to be taken into account when you create the IK handle, if you don't need them, I'd delete those keys.
• Your arm joints have rotations on them (they aren't all at 0) when in your original pose. This causes major problems when creating an IK chain.

Here's some solutions:

• Unbind the skin, delete the keys on your joints, freeze their rotations, then use the orient joints tool to make them face the proper direction (if orienting joints isn't something you've learned about, definitely look into it before going further. It's immensely important to rigging.), then you should be able to rebind to the skin and create your IK handle. It should function properly then. This is the long solve, but it's more proper than the next one.
• Alternatively, you can just right-click-hold on the shoulder, elbow, and wrist joint, then float to the option that says "Set preferred angle" (should be to the left of where you click-hold). Then apply the IK handle, that should make it function properly right now. Keep in mind that this doesn't get the rotations off your joints, this can cause any number of problems for you or the animators using your rig once things get going. It's easiest to solve this before you get a full rig built, so I'd recommend taking the steps in the first solution because that's the "right" way to do it.

Hope this helps, let me know if you have any questions (the steps in the first solution are kind of vague, so I can go into more detail if you can't get it done from what I've written).

[Anonymous]

Wow, thank you for such a detailed description, I cant tell you how appreciative I am. I'll definitely look into what you described in the first step. I'll let you know how things turn out! Thanks again!!

[Anonymous]

Okay. I've followed your instructions for the first step and I have the IK Handle on the arms working! Thank you! However I want to make sure I haven't screwed anything else up, so I was hoping if you could maybe take a look at the scene file and go over it? I would be very grateful.

[Anonymous]

Hey! Yeah, it looks fine. The only thing I noticed is that your wrist still isn't oriented the same as the elbow and wrist. That doesn't matter for the ik solver since it's the end of the chain, but it would be best to make sure it is oriented properly to prevent confusion for the animator that uses your rig. Good luck! Let me know if you run into any issues!

[Anonymous]

That's good to know. I'll make sure I get those wrist rotations corrected. Thanks again for all your help man, I really appreciate it 🙂

[haiqalfitri345]

Hello, I'm having the same problems and I also looked at the issue you mentioned but I don't see any issue. Please help me because I stuck at this stage for a few days.

[matias.martinez3NAW2]

Thank you a million times! You solved the issue I had at work!