(Vuforia) Track an object in real world space without using targets

Basically what I'm try to do is click a button and spawn an object in the real world space, maybe in front of the camera. Then I can walk anywhere and the object will always be where it spawned.

I know this can easily be done with ground plane and plane finder, however, only specific phones support that and I do not have any of those phones.

Is there any other way I achieve this?

I've tried:

Using an image target to activate an object that is a child of the camera, then decouple it from the camera so it exists without a parent. However, the object pretty much just follows the imagetarget around. It still does this even after I return from OnTrackableStateChanged. Even after I DESTROY the image target as well. It just follows it whenever the image appears in the screen.

 

Hello,

Long ago, we internally prototyped an app that utilized our User Defined Targets feature in combination with the Device Tracker. It was called "Find the Penguin" and was meant to address limitations of the original Pokemon Go! experience, which did not allow you to approach a character. So, it has been done with past versions of Vuforia and was not device dependent.

We removed the app once the Ground Plane feature was commercialized.

Thanks,
Vuforia Support

 

Sorry if I'm misunderstanding this, but does that mean the only way to do this in older devices is to use an older version of Vuforia?

 

Hi @chuakc92 , ground plane and plane finder technology (or S.L.A.M./markerless tracking) usually requires a mix of motion sensors (gyroscope, accelerometer) and the camera.

It is still common for Android devices to be released without gyroscope, therefore your target devices is always smaller than with marker tracking. Further, Vuforia ground plane has an even narrower (but growing) list of supported devices with ground plane.

I would suggest to research other AR libraries that support SLAM/markerless tracking. There are a few of them out there.

Moreover, I would advice you to experiment and research a bit more how Vuforia AR works in Unity, try observing the position values changing live in the Editor Inspector and try changing the Center Modes in the VuforiaBehaviour component in the Scene Camera. Hopefully, this will help you understand more about AR coordinates work.

When you finally understand how the coordinates references work, here's a suggestion:
- Track something with an image target/user generated marker.
- Use extended tracking (option that can be enabled in Vuforia settings), or use the gyroscope in your device to move your camera when you lose track of your marker (note that gyroscope can only detect the device's orientation and not positional movement).

 

Hello,

Apologies for the ambiguity. What I was trying to say is that Vuforia once solved the Ground Plane use case before the feature was available by using a combination of the "legacy" features User Defined Targets and Device Tracker. This was demonstrated in a short-lived sample called Find The Penguin, which may still live somewhere on the Internet.

Both of those legacy features still exist, but are no longer needed with the launch of Ground Plane and Fusion (e.g. ARCore/ARKit). These provide 6DoF Device Tracking capability that performs much better than our use of a combination of legacy features.

This *may* provide you with an option to have a plane finding experience on devices that are not currently supported by Vuforia.

Thanks,
Vuforia Engine Support

 

-----------------
I understant that , Vuforia has Ground Plane and I can create any object anywhere.
but the question he asked and also I want to ask it. if I have a image target and a video will be played after I scanned it.
the video continues playing while the camera finds the image target and if I moved the camera away , the video stops.
now how can I keep the video still playing even if I moves away from the image target itself ?

 

Hello,

Image Targets has a related feature called Extended Tracking. This is a robustness feature that allows for 6DoF poses to be returned for a target that is no longer in the camera's field of view. What the developer does with this data is app layer logic.

Vuforia Core Samples on the Unity Assets store demonstrates one possible video playback use case. In the past, our sample behavior would be to transition from a registered experience (video playing on a target) to a full-screen video playback when the target was no longer in view.

Thanks,
Vuforia Engine Support