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Sample has no stable tracking

November 28, 2016 - 9:09am #1
Topic solved

Hi

i have Unity 5.4.0f3-HTP Personal and Vuforia 6.1.17.

I am running the Hololens sample with he teapots and the stone markers. I am able to deploy to the Hololens and the marker is recognized but when i walk around the marker the tracking is not smooth. The teapot jumps to a new position every time i move around the marker or move my head slightly. Its feels like Vuforia resubmits the position to Hololens, after i move by a significant amount. Only when i dont move and keep my head in the same position the teapot stays at the same place.

According to documentation https://library.vuforia.com/articles/Training/Developing-Vuforia-Apps-for-HoloLens

the procedure should be this

  1. Vuforia’s target Tracker recognizes the target
  2. Target tracking is then initialized
  3. The position and rotation of the target are analyzed to provide a robust pose estimate for HoloLens to use
  4. Vuforia transforms the target's pose into the HoloLens spatial mapping coordinate space
  5. HoloLens takes over tracking and the Vuforia tracker is deactivated

So after step 5) Vuforia should disable itself and not readjust the position. But instead it keeps tracking and resubmits new positions if the head is slightly moved. I verified this in Debug mode, where every time Vuforia finds a target it does a Debug.Log message.

If you disable extended tracking, Vuforia runs all the time and the tracking is smooth but the teapot disappears as soon as the marker disappears. In extended mode the teapot persists even after the marker is removed, but if the marker is visible i get the aforementioned jumps. 

Does anyone else has a similar experience?

 

Thanks

Dimi

Sample has no stable tracking

December 13, 2017 - 12:54pm #5

@medabit and others, I did get it work in HL by printing the target image that is print out exact size as when upload and specified in Unity. However, if the HL keep looking at the image, the tracking is shifted a bit and then it came back, kind of unstable. Is there a way to improve it.

I already turn on extended tracking and I am using vuforia 6.2.10 with Unity 5.6.

 

Thanks

Truyen

Sample has no stable tracking

October 25, 2017 - 9:55am #4

Confirmed. Marker size is the issue. Make it the same size and your print will solve it.

Sample has no stable tracking

November 30, 2016 - 8:24am #3

Actually I managed to get much smoother tracking now.

It turns out that my printed marker was not in the correct size. Hololens and in general stereo augmentations have a problem with this.

For stereo rendering, all scene units must be specified in meters. Additionally, all printed targets must be the exact same size as specified in the device database. Resizing, stretching of the printed target will affect the registration accuracy of the augmentation.

In the sample the image target width size was 0.247 and height 0.1729, so i printed a new marker of size 24.7 cm and 17.2 cm and the issue was fixed.

My previous printout was much smaller.

The solution came form here

https://developer.vuforia.com/forum/hololens/axis-movement

Sample has no stable tracking

November 30, 2016 - 8:07am #2

Hello,

If the image target remains stationary, and extended tracking is enabled, then HoloLens tracking will be utilized and you will see solid registration. However, if the image target is moved, there will be a lag in augmentation registration on the target as Vuforia recalculates the position. This is a known limitation of our integration with HoloLens that we are working actively to resolve.

Thanks

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