Hello everyone.

We have decided to phase out the Mixed Reality Forums over the next few months in favor of other ways to connect with us.

The first way we want to connect with you is our mixed reality developer program, which you can sign up for at https://aka.ms/IWantMR.

The plan between now and the beginning of May is to clean up old, unanswered questions that are no longer relevant. The forums will remain open and usable.

On May 1st we will be locking the forums to new posts and replies. They will remain available for another three months for the purposes of searching them, and then they will be closed altogether on August 1st.

So, where does that leave our awesome community to ask questions? Well, there are a few places we want to engage with you. For technical questions, please use Stack Overflow, and tag your questions using either hololens or windows-mixed-reality. If you want to join in discussions, please do so in the HoloDevelopers Slack, which you can join by going to https://aka.ms/holodevelopers. And always feel free to hit us up on Twitter @MxdRealityDev.

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 -
https://forums.hololens.com/discussion/1652/holograms-moving-when-it-doesnt-supposed-to
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 !

Comments

  • Peter_NZPeter_NZ ✭✭✭

    Wow 10-15cm is quite a bit. We are doing something similar with building models (www.revitholoview.com) 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.