ARKit body tracking (ARBodyAnchor) broken in iOS 18.0 + 18.1

I'm wondering if anyone can suggest a workaround for the broken ARKit body tracking in iOS / iPadOS 18.0 and 18.1?

The orientation for foot bones (and possibly other bones) is incorrect in the ARBodyAnchor returned via ARView.session.delegate update method. It works correctly in iOS / iPadOS 17.x.

The same failure occurs in a SceneKit app via a ARBodyAnchor in ARSCNViewDelegate.

You can easily verify the problem using Apple’s own sample app: https://developer.apple.com/documentation/arkit/arkit_in_ios/content_anchors/capturing_body_motion_in_3d

Any help would be greatly appreciated.

Anyone, especially an Apple engineer, have any ideas on this problem? I submitted both a Feedback request (FB15465734 ) and a Code Level Support request almost a week ago and have not heard anything back on either one. We’d like to update our app ASAP but we don’t know how to work around this regression in ARKit.

The problem seems to be fixed in iOS 18.2 Beta (Build: 22C5109p).

ARKit body tracking (ARBodyAnchor) broken in iOS 18.0 + 18.1
 
 
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