# Questions tagged [inverse-kinematics]

For questions about using IK in rigging. Inverse Kinematics is the opposite of the default Forward Kinematics. Instead of posing each bone in a chain from the base to the tip, IK solves the rotations of preceding bone(s) in the chain automatically based on the position of the IK-constrained bone.

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### Inverse kinematics not working as expected with a chain length greater than two with pole target

I'm trying to make animations featuring a stick figure, I got the idea to have its limbs in the rubber hose style like those seen in old cartoons where the limbs of characters bend in unnatural ways. ...
27 views

### IK problem with a rig made from scratch

I made this rig following a Blender rigging course. It has IK leg bones with poles parented to a foot roll bone setup. The problem is, when I spin the root bone, The IK gets messed up after the ...
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### How to link the rotation angle of multiple bones to a single value?

How can I have the IK X rotation Max. Value for multiple bones link to one specified value for the IK X rotation Max. Value? I’m thinking along the lines of having a bunch of cells in Excel link to ...
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1 vote
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### Bone Roll with IK not working as expected

I was trying to apply weights to my mesh and I discovered that the "roll" (not sure if that is the best term) for the thigh bone is off by 90 degrees. When I disable the IK restraint on the ...
39 views

### Parent -> child wobbling, witching, shaking inverse kinematics

When I was simulating a car using the Launch Control addon, I noticed that the parented driver (a character) does not follow the animated car correctly, shaking intensely. A similar phenomenon occurs ...
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### IK angle limits not restricting IK movement

I have a basic arm setup with two bones and 1 control bone coming off the end of the forearm. I’ve locked IK rotation on X and Y to min/max = 0 and set my Z min = 0 and Z max = 45 on the two bones, ...
• 93
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### Why won't these IK bones rotate?

I'm trying to be able to bend this 1/4" thick sheet metal from flat to 90 degrees using an IK rig, but the IK constraint sub-target named "last_IK" (cone shape in pose mode) barely ...
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1 vote
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### How to keep this Inverse Kinematics setup from rotating out of plane? [duplicate]

How can I lock this IK setup to only allow rotated in the perpendicular plane (in the view it's the XZ plane)? Ideally this is supposed to be a piece of flat sheet metal on a floor with an IK rig to ...
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1 vote
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### IK rig. Bone jumps to IK bones location in pose mode

arm L bone has an IK modifier on it to arm IK L bone. When I go to pose mode arm L bone ...
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### Inverse kinematics for pre rigged model in sketchfab titanus scylla

I downloaded this Titanus Scylla model from sketch fab https://sketchfab.com/3d-models/titanus-scylla-eb99bfcc05bc42ac9477738c4e9b6641 It’s prerigged but when I go into pose mode and I move around a ...
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1 vote
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### Blender Pole Target Rotates Wildly When IK Target, PoleTarget, or Any Other Bone Gets Moved

I have IK constraints all over this thing, but the knees are broken. They were fine when I first made them, and now they're doing this: Crazy Knees Being Obnoxious via Imgur I've tried replacing the ...
1 vote
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### Cannot get IK armiture to bend its knee correctly

My Armature model is a biped creater that has 4 bones per leg. thigh,calf, foot and then an IK bone. I have the x and y axis locked but as you can see with the blue line the z axis should allow the ...
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### IK not tracking to target

I've been making an IK mechanical arm/connector for a project of mine, and I cannot get the bones to properly track to the target. Most of the bones have rotation constraints in the IK menu, but even ...
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### IK Mechanism Snaps Back To Normal Pole Angle After Moving A Bone After Mirroring Pose

Whenever I mirror a pose when animating, the pole angles on the legs flip unless I move one of the bones, then the IK mechanism snaps back to the normal pole angle. I know the problem is only a click ...
1 vote
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### I'm struggling to make an ik for a robotic leg

I've used Ik's before on human rigs but never anything else. I'm making a robotic leg thing and the Ik works but I'm not sure how I'd keep certain objects from stretching and deforming well keeping it ...
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1 vote
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### Character Rig - Knees Bending Incorrectly

I've been working on a custom character rig for my online image for the past while now, and I've managed to model my character with a decently working rig and somewhat-reasonable control blocks ...
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### Hand rigging with reverseIK fingers and pole vectors?

I am currently trying to rig a walking hand and ran into some issues. Basically what I want to achieve is a Hand that is walking on its fingers (like the one in the show Wednesday for those who know). ...
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### What vectors does the IK constraint align when using a Pole Target?

For a research project, I need to reimplement Blender's constraints with behaviour as close as possible to their Blender implementation. I am currently struggling to understand how the inverse ...
42 views

### Kinetic Rigging Question (Theo Jansen Style)

I'm trying to make kinetic mechanism, like link below. https://www.youtube.com/watch?si=Hn93VdvYxKf5NsK_&v=NM4q-f68TlY&feature=youtu.be Added armatures and IK constraints to the points that ...
1 vote
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### Problem when animating with IK blender 4.0

Well, I'm a beginner, and I was watching a tutorial on the basics of Blender. Right now, I'm stuck here. I got the IK, but the problem is when I try to animate it, for example, crouch, legs open to ...
29 views

### IK weird behavior

I always use a simple IK setup for the arms : Wrist IK ( Target Elbow ) + Elbow IK ( target Shoulder 2 ) Wrist + Copy rotation modifier with Wrist IK as target It always worked on thousand of model ...
1 vote
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### IK Chain Confusion: Unable to affect hand's rotation without affecting whole chain

I've built about a dozen IK chains before. I must be going senile over here. When I rotate the hand control in what I believe is a standard IK setup, the entire arm rotates. I am unable to affect only ...
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### Rigging Issue: Rotating bone rotates object on wrong pivot point/wrong way

I have been trying to rig a drum kick pedal, and found a free rig online. I copied the rig for the kick pedal, but for some reason, the pad that is supposed to rotate, does not rotate in the same way ...
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### Rigging - Push object along specified axis (probably IK problem)

I have three shapes like this on graphic below. Objects A and B are connected with object C and I'm trying to get object B translated along Z axis only when object C pushes it due to rotation of ...
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### Why IK shoulders coming unattached when animated?

I'm pretty new to rigging. My robot friend here has IK arms with pole targets for the elbows. He's animating nicely but his shoulders are not appearing to stay connected when dramatic spine movement ...
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1 vote
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### Can I make IK robot elbow face a persistent direction like in FK

I can't get the IK arm to behave the way I'd like. There are bones behind the arms that are used as pole targets. When the pole targets are active the elbows behave nicely but the shoulders rotations ...
• 101
1 vote
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### Fk to IK on arm is causing arm to rotate

When I change from FK to IK on my character's arm the bicep rotates, what is causing this and how do I fix it? I think it's something to do with the bone locations in the arm but I'm not sure how to ...
65 views

### Why won't my robo arm spin right?

I'd like this shoulder to spin only along the x axis whith the IK of the arm. The IK Lock axis switches aren't doing much though. I need everything to deform mechanically and rigidly adhering to those ...
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1 vote
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### Simple rigging problem (or not simple at all)!

I have a problem that seemed simple to me, but whatever I've tried that turned not to be that simple. I have 2 opposite L shapes with fixed rotation center. Their ends are connected with lever. At ...
• 180
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### I want one controller to affect the whole Rig

I have created a rig that moves all the desired parts but I need one main control to affect everything at once such that individual controls rotate around allowed axis when that main control is moved
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### How to lock bone rotation on global axes in IK rig?

I'm working on a rig for a robotic leg and I want to have a simple, 2-axis joint connected to the foot (see screenshot). However, I can't seem to get the joints to only move on their axes. I can get ...
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### Calculate the location of the bones in Blender from BVH

I know that bpy.ops.pose.paths_calculate can be used to calculate the position of a bone at any time, but I don’t know the details. My task is as follows: first, a ...
56 views

Blender community, I hope you are all well. I am fairly new to Blender and have been experimenting with animation through imported assemblies I have created in Autodesk Inventor. It has been ...
31 views

### rigging with inverse kinematic

I would like to encourage a movement for this model. Does it make sense to use inverse kinematics here? How should I proceed here? I have already tried to recreate this with bones, hopefully it will ...
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### Problem with auto IK, some bones turned stiff (Auto IK doesn't work)

First time working with armatures and IK, I had a rig working and somehow I did something that broke it. I'm using the Auto IK option for it. It's a 2D spider (don't mind the leg count) and each leg ...
22 views

### Bone rotating in IK despite axis lock

I have an ik chain of 2 bones. I have it set so that the first bone has a y axis lock but the second bone has an x and z axis lock. In spite of this, when using the ik, the first bone still rotates in ...
138 views

### What's an IK Setup that Allows Hands to Stay Planted?

After some months of learning Blender, I've reached another roadblock. I looked up an IK setup for feet and legs, which works great with no complaints. I then started work on an animation involving ...
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### Bone constrained to external object, how do I edit or remove this constraint?

So I created a character model a little while ago, did some animations that involved that character being in handcuffs, and do so this, I somehow constrained the IK controller of the hands to the hand ...
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1 vote
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### Setting inverse kinematics relative to local coordinates of an object

I’m just studying rigging, and I have a non-trivial problem that I can’t solve on my own. I’m trying to create an IK with a limiter for the mechanical limb. When I rotate the object relative to the 3D ...
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1 vote
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### Armature Posing Abnormal Hip Line & Legs Cave In

I made an armature and connected it so a stick figure I made. The issue I'm running into is when I bend the knees of the armature. The upper thighs of the figure begin to cave in, and a line appears ...
89 views

### Corrective shape keys for IK-driven bone

The bottom bone here is affected by an IK chain: Unfortunately, it's rotational value doesn't change unless I rotate the bone directly. This is a problem, because I want to use it's rotational value ...
• 319
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### IK for servo-based robotic arm

I'm looking to model a very basic servo-based robotic arm using IK in blender. I have an armature with two bones (1 joint where the bones meet). I've enabled IK as an Empty on the tip of the last bone,...
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### Toggling IK on and off will change the bone's transform position slightly

As stated in the topic, whenever I turn on/off the IK bones, their positions drift a little bit. And I cankeep changing their positions by keep turning them on/off. Why is this happening? And how do ...
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### Bar Linkage - Inverse Kinematics

I am trying to make a linkage assembly using inverse kinematics. I have two arms parallel to each other which are to rotate with one another, while a link connects the two and is to stay parallel to ...
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### Why does a stretch IK shrink?

I have two IK chains for my leg. One has stretch enabled, the other one doesn't so I can blend smoothly between them. In the default position the two chains align perfectly. Something I've noticed ...
57 views

### Model's wrist shrinking with IK arm rig

I'm trying to animate a shot where my character looks at the palm of their hand, but the wrist shrinks when its rotated. I know the rotation should really be in the forearm but I don't know how to do ...
58 views

### Auto keying in real time works incorrectly with inverse kinematics

When recording an IK chain's motion in real time, the resulting animation does not match what was gestured during recording. What I gestured: What I got: Is this a bug or am I missing something? I'm ...
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### How can I stop IK bones from spinning randomly?

I'm trying to rig Oleg Ushenok's Mech Spider. I'm using IK bones for the little pistons that are all over the model. I like the 3 part motion that it gives rather than the typical piston setup. The ...