ARSkeleton3D modelTransform always return nil

Spatial Computing ARKit
alexander295 OP
Created Oct ’25
Replies 5
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I use ARKit for motion tracking. I get the skeleton joint coordinates and use them for animation. I didn't make any changes to the code, but I updated the iOS version from 18 to 26, and modelTransform now always returns nil.

https://developer.apple.com/documentation/arkit/arskeleton3d/modeltransform(for:)

For example

bodyAnchor.skeleton.modelTransform(for: .init(rawValue: "head_joint"))

bodyAnchor is ARBodyAnchor.

I see the default skeleton on the screen, but now I can't get the coordinates out of it.

I'm using an example from Apple's WWDC presentation. https://developer.apple.com/documentation/arkit/capturing-body-motion-in-3d

Are there any changes in the API? Or just bug?

Replies  5
Boosts  0
Views  670
Participants  3
alexander295 OP
Oct ’25

Device iPhone 16 pro iOS 26.0.1

0
Vision Pro Engineer OP
Apple
Oct ’25

Hello @alexander295,

It would be helpful to file a feedback for this issue at https://feedbackassitant.apple.com.

Once you do, please post the number here.

Thank you

0
alexander295 OP
Oct ’25

FB20684856

0
MaksBarbaruk OP
Oct ’25

I think I have the same issue, all body tracking feature is now broken for iOS26 devices (works fine with iOS 18). Any updates here?

0
alexander295 OP
1w

iOS 26.1 (23B85) still the same issue.

0
ARSkeleton3D modelTransform always return nil
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