Log in or register to post comments

Keep model in world space when tracking is lost

June 6, 2019 - 6:20am #1

Dears,

 

I work on an Android Unity app which implement Vuforia.

 

The concept :

In AR I recognize an object, I put over an animated 3D Model stuck on the real object.

 

I need that the 3D model stay stuck to the real object even if the tracking is lost.

 

I already check to :

- Set the tracking mode as POSITIONAL

- Set the device type to Handheld

- Set the world center mode to DEVICE

- Comment the OnTrackingLost() method

 

Currently the 3D object disappear when target is Lost or drift if we try to turn around in the room.

 

Do you have any advices please ?

 

Kind Regards,

MF

Keep model in world space when tracking is lost

June 12, 2019 - 8:51am #7

Hi,

 

Please do you have a snippet code on how to implement that ?

I don't know where to find the the world coordinates of the 3D model transform (I always have the local) and on how to disable tracking.

 

Regards,

MF

Keep model in world space when tracking is lost

June 11, 2019 - 11:30am #6

Hello,

One approach is to:

  1. Store the latest reported pose (which is is world coordinates)
  2. Turn the ObjectTracker off and the use the old pose to display the object

Or, in Unity, you can detach the augmentation from its parent trackable with Transform.setParent(null, true);.

The drawback to both is that your augmentation will no longer update its pose, so alignment usually goes slightly off as one moves around the target.

Thanks,

Vuforia Engine Support

Keep model in world space when tracking is lost

June 11, 2019 - 12:49am #5

Hi,

The real object has been detected and the 3D model pop in the right way over it.

My question is about how to fix it in the world space once he is detected.

 

I was thinking to override thposition of the object model target in the world space with the sensors informations but I doesn't found how to access the world space transform position of the 3D object.

 

What do you think ?

 

Kind regards,

MF

Keep model in world space when tracking is lost

June 10, 2019 - 10:51am #4

Hello,

mfreville wrote:

I'm always stuck to this issue where the 3D model disappear or drift when we turn around the real object.

Please note that Vuforia Engine Model Targets tracking does not support objects that are moving or can articulate: https://library.vuforia.com/content/vuforia-library/en/features/objects/model-targets.html

"The object must:

  • Be geometrically rigid (i.e. it cannot be deformable or malleable).
  • Present stable surface features (shiny surface are not supported).
  • Be fixed with respect to the environment it is in."

Thanks,

Vuforia Engine Support

Keep model in world space when tracking is lost

June 7, 2019 - 1:57am #3

Hello,

 

I'm always stuck to this issue where the 3D model disappear or drift when we turn around the real object.

 

I will need to fix it in world space when it's detected.

 

Kind regards,

MF

Keep model in world space when tracking is lost

June 6, 2019 - 3:30pm #2

Hello,

I'm unclear on why you're using DEVICE as your world center mode.

World Center Mode defines which object in the scene will serve as the origin ( 0,0,0 ) of the scene's world space:

  • SPECIFIC_TARGET allows you to select which target is used as the scene origin
  • FIRST_TARGET uses the first target detected as the scene origin
  • DEVICE uses the ARCamera as the scene origin

AR experiences that are registered to the target typically use FIRST_TARGET or SPECIFIC_TARGET.

Thanks,

Vuforia Engine Support

Log in or register to post comments