I'm having a similar problem.  Only one object is recognized and others are never recognized, but if I restart then a different one will be recognized but no others.

I guess you have to increase the "Max Simultaneous Tracked Objects" amount to whatever you like.

If you are using the Unity plugin you can find the variable under "Vuforia Behaviour" in the AR Camera prefab.

I've done that and it doesn't seem to make any difference.

I've also run into the same problem like you.

I'll try to fix this and report back if I find any solution to this problem.

I am in the same boat. I see that there is a Vuforia session at Unite LA in a couple weeks, maybe I can corner a real live person there and demonstrate the issue. =)

My multiple object recognition seems to be working. It tracks the two objects in my database. The only thing is that it only recognizes one object in the frame at a time. When the two objects are in the camera frame, it only recognizes one of them. But I can individually point at either object, and it tracks it with a gray box. 

adriancabal,   What device are you using?  Are you using Unity?  How have you set up your project?

I'm using a Samsung Galaxy S6 to test the app. For development, I'm using the latest Vuforia Sdk for Android Studio (vuforia-sdk-android-6-0-117), and the latest Vuforia Object Scanner apk (scanner-5-5-11), on a windows 10 64 platform. I just included two objects in the target database and copied/pasted the _OT.dat and _OT.xml file in the VuforiaSamples-6-0-120 project under app>src>main>assets>ObjectRecognition folder in Android Studio.

Now when it says "recognize and track up to 2 objects simultaneously", I'm not sure if it means that it can track both objects when they are both inside the frame of the camera and see two gray boxes simultaneously.

Because when I tested it, it didn't recognize them when both were inside the frame of the camera. But when I included only one of the objects within the frame at at a time, it was able to recognize and track it with the gray box.

After your reply I also tried to use Object Recognition in the Vuforia SDK for Android Studio. So I downloaded my database with three targets in it and put the _OT.dat and the _OT.xml in the ObjectRecognition assets folder. After that I only changed the line whoch loads the xml-file (mCurrentDataset.load("ObjectRecognition/objectTarget.xml").

With all this set up I build the sample app to my Galaxy Tab S2 and tried the recognition. But I it end up with the same issue like in Unity. pointing on the first Object: It gets recognized and the app draws a transparent cube on it. But then pointing at the second target just does nothing. Pressing back on my device and reselect "Object Reco" but now pointing on the second target: My second object gets recognized and gets its cube on it, but pointing back to the first object just does nothing.

There must be something I missed. Any suggestions?

Same issue for me.

I have 3 objects in my database, and I'am only able to detect 2 of them, the third one is never detected.

If I restart the tracker, I can detect the third one, but the first isn't detected anymore...

Please help !

EDIT:

I tried putting only one object target per dataset and activate one or the other at runtime, and it's causing the same issue.

the first object is detected, and if I activate another dataset containing an other object, it will never detect it...

Hello,

With respect to the issue reported where only the first target detected in a database can be recognized, we are actively reviewing the issue.

Thanks

Hello,

This issue has been fixed as part of Vuforia 6.2. There should be no need to regenerate your datasets, only upgrade your project to the 6.2 release artifact.

Thanks