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Vuforia Marker Based Tracking Issue

Overview: I am developing a Unity project for HoloLens 2 that uses Vuforia marker based tracking to track various objects. I have encountered an issue with both standard tracking and extended tracking. When I look at my image target, all tracked child objects appear and are in the correct relative positions. However, when I shift my own perspective while wearing the HoloLens, the tracked objects shift positionally to some extent when I need them to stay in the same position regardless of the perspective. For example, I turn my head to the right and the objects move to the right. There should only be movement of child objects when the actual tracked image moves. To clarify, whether the object is directly tracked, or extended tracking is employed, the child objects still change position depending on how I am looking at the tracked image.

Here is a list information that may be helpful:

  • I am using the most recent versions of Unity and Vuforia
  • The image target is a child of the AR Camera (I still have the issue whether or not the image is a child of the AR Camera)
  • This issue can be replicated in sample projects
  • I have tried AR camera with both World Center Mode as DEVICE_TRACKER and Camera
  • I have read through the current forums posts regarding this issue and the general consensus seems is to use extended tracking but the issue still persists
  • The image target in the Unity project is properly scaled with the real image target
  • I have tried using multi targets and customizing my own targets by modifying the dataset configuration XML File
  • "Track Device Pose" and "Load Object Targets On Detection" are enabled
  • I am using 5 star images

 

Here is a link to a video someone else made regarding a similar issue:  youtube.com/watch?v=E2rZs2RQWvg

Thank you for your time.

Hey there,

 

Thanks for reporting the issue. Is there any possibility you can provide your own video of the issue on the Microsoft Hololens 2?

We are also having the same issues .  That is, significant jitter associated with the position of graphical objects in the scene when the user moves their head even small amounts.

Hey there,

 

Would you be able to share in detail the similar tracking issues that you're experiencing? Another video would be very helpful of the device tracking.

 

Kind regards,

Patrick Scheper

Here's a video (especially the first 15 sec) that shows the jitter associated with objects placed on the image target when moving the head.  You can also see the tracking latency/error associated with keeping the head still and moving the image target.&nbsp

Hello,

AR_CONTROLLER (DYNAMIC) is the "pure CV" mode and was implemented for just this use case.

Kind regards,

Dave Downing

Vuforia Engine Technical Support

Thank you very much Dave. We were able to experiment enough with the different modes to get a better understanding of the problem.

Hello @LennartM,

[quote]

We have a static testbed where we feed the same image every frame to a virtual camera and run Vuforia on that. We noticed that there is a bit of noise, up to +/- 0.2mm between different frames for the position estimate.

[/quote]

Thanks again, Dave. I understand that there is jitter, and the resolution/accuracy is fine, but I was wondering why the jitter is different per frame in a static image?

Hello,

What you're observing are artifacts from optimizations made in our tracking algorithm to run on embedded systems.

Kind regards,

Dave Downing

Vuforia Engine Technical Support