How can I track a object with two vive tracker?

[jackieyang]

I would like to track an object in VR for research purposes. However, with only one tracker, the object could often occlude the tracker in a certain orientation and result in object appears in a different location than it actually is. I'm considering using two Vive Tracker to improve its tracking quality, but I cannot find any API so that I can know whether one of the trackers is occluded by the object. Any suggestions?

[dario]

Hi Jackie,

 

Having done body tracking with 3+ trackers the best recommentation I have is to avoid occlusion as much as possible by placing the base stations as high as possible pointing downwards 45 or more degrees (depending on the height of the base stations).

 

There aren't occulsion APIs that will tell you which sensor got occluded or not as you couldn't assume all loss of tracking is occlusion from another tracker or if you are simply out of range.  I suppose you could calculate the possible occluson of the other tracker based on last known positions relative to the base stations but ideally the placement of the trackers should be in the best optimal location to avoid this issue in the first place.

 

For the Vive trackers I would recommend studying the diagrams in the developer documentation that not only show optimal placement for tracking but also the hotspots regarding bluetooth connectivity. You can find the developer guidelines at https://developer.vive.com/us/vive-tracker-for-developer

 

If your research does add additional insights regarding optimal placement or about handling occlusion please do share you results here.

 

best,

Dario

[dario]

If you're trying to track an object that you toss around e.g. a ball - the solutions I've seen use a transparent case. If you're attaching it to a mobile phone based hmd then you should attach it on the top of your head with some distance between (use a camera mount of sorts)