Alignemnt and Accuracy issue in Holograms

Hello Everyone,
I am currently working on developing a Hololens app for Engineering drawing visualization.
I use Unity 5.2, Holo-toolkit, and vuforia to build the app with CAD drawings of size ranging from 3 to 30 meters in width and 1 meter in height. My test with 3 meter drawing was raltively successful in Terms of placing the hologram, alignment and accuracy of dimentions. I still had some accuracy tolerance but it is within acepatble range (10 mm for a 3 meter drawing.). Now when I am using large drawings, I see significant isssues with the alignment and accuracy of dimentions.

The process - I render my drawing as Images as texture on cube. I use vuforia markers for Placing the drawing on a wooden board. I scan three markers to define a 2D plane and use that plane to align my drawing. I use world anchor to fix the drawing.

The Problem - While I scan the Points with vuforia, I get valid Points (I draw a marker to check this) but once I am done with all marker scanning and I load my model, the model shifts (alomng with the markers) by roughly 10 - 15 cms (for a 22 meter drawing).

**What I have tried **-
1. I checked the Performance Settings as suggested in post -
The app FPS is around 35.
2. I tried to remove the scanned spaces from Hololens, this stopped a flow effect in the app but the shift of Drawing is still present.
3. I performed sensor Tuning, eye caliberation.
4. I tried to reduce my model size to 1/4 th of ist original size. Original was 35mb. But I see same issue with both apps.

Let me know your suggestions to tackle such issue in Hololens.

Thanks in advance for your help !


  • Peter_NZPeter_NZ ✭✭✭

    Wow 10-15cm is quite a bit. We are doing something similar with building models ( and we generally don't get any more than 2-3cm. I have no experience with Vuforia and how it works - but it looks like you are not applying a world anchor.

  • Thanks for your comment Peter!
    I am indeed using world anchor on my game object. The 15 cms offset is for drawing if 22 meters. How long is your model ?

    Can you describe how you prepare your hologram ? What technology you use for placing hologram on physical object?
  • Peter_NZPeter_NZ ✭✭✭

    We have models of different sizes and I think the longest is 100 meters. Have you tried not using vuforia? The reason why I suggest this is we have our own marker system and when we aligned our model to markers but the markers had no anchor then the drift was significant.

  • Thanks for your reply, Peter! May be its worth a trial to check how are the results without Vuforia. I will check and post results.

  • Hey, have you fixed this question mentioned above? I met the same questions as you, and it would be better if you can give me some practical advice. Many thanks!

Sign In or Register to comment.