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Multi-Vumark for large scale object

By I33N on Sat, 10/14/2017 - 13:00

Hello,

In an upcoming project I want to track and augment a big sculpture. It's kind of a cylinder, 3meter diameter 5m tall.

I want people to move around the cylinder and see an augmented sculpture through their tablet. They might get closer at the beginning than go few meters away and look up and down a little bit.

 

The tablet has to be Windows based so I can't use a combination of Vuforia + ARKit or ARCore to start positioning the virtual cylinder to the real one using a marker and than finish the tracking using SLAM. I have to use Vuforia only and their SLAM based approach is not released...

 

What I wanted to do is to print about 50-100 big targets, 40cm squared and to stick/hang them around the cylinder at fixed known position/orientation relative to the cylinder.

 

I saw that Vuforia has a multi-target feature but it seems more focused on small scale object than on big scale. Has anyone used it for larger scale objects?

Also if I want to create 50-100 targets I thought that VuMarks are a better choice has you can easily generate 100.

I though that I could use the VuMark ID to deduce its position/rotation so I could go from one vumark to the other using extended tracking if none are visible and switching from one to the other without loosing the augmentation.

Maybe using the wolrd center mode or the unified coordinate system or with custom software to get the augmentation transformation to the camera.

 

But in Unity the VuMark component doesn't have a predefined ID so I can't place several Vumarks around my cylinder with a fixed ID.

 

Any idea how to solve my problem? Any feature I didn't think of to handle this kind of problem?

Is it too optimistic?

Thanks a lot,

Ben

Hello I33N,

You can pre-generate and print out your VuMark instances. Review this documentation to get more information on this:

https://library.vuforia.com/content/vuforia-library/en/articles/Solution/Working-with-VuMarks.html

Thank you for your answer.

 

My concerns wasn't about generating 100 VuMarks, I am used to the API and to working with VuMarks.

 

Alright, I understand better what you're trying to do. You are right, for VuMarks there will only be the one object pre-defined in the scene to represent all instances, but I believe there is a way to handle your use case.

So the two options are VuMarks and Multi Targets and unfortunately they don't work together.

medabit

Thu, 02/21/2019 - 19:23

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Hello @Econstann,

Using a small target (VuMark) to track a large object (building) is a challenging use case, and does not lend itself to tracking accuracy. Extended Tracking can result in inaccurate poses, depending upon several factors including the environment and the target.

Econstann

Fri, 02/22/2019 - 10:06

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Thank you for your answer. Tracking with a VuMark however is not my problem. I previously tried Model targets but found there weren't fitting,especially since the house will not be built at the time of augmentation. VuMarks printed on A0 paper work very well.

Hello @Econstann,

Thanks for the clarifications.

You say you're trying to manipulate the position of the augmentation through code. Can you elaborate a bit more on how you're doing that?

Hello medabit,

If I do not reposition the augmentation is does appear registered to the VuMark exactly how I positioned it in the Unity Scene view. My current respositioning works as such:

Hello,

Thanks for the clarifications. Nothing obvious comes to mind.

Econstann

Wed, 02/27/2019 - 09:20

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Hello medabit,

Thanks for your response. Can you maybe explain what you mean by handedness? I will run a few tests with different models to see how it behaves.

Cheers,

Econ

Econstann

Thu, 02/28/2019 - 14:52

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I've discovered the solution to this. It had to do with my world center mode upsetting the world positions I was giving the target. It works now that I've set my world center mode to first target.