Question Vuforia Questions about Image Target local position

Hello

I have a problem creating the application, so I am asking a question.
First, when AR Image Target is detected, a floor is installed on Image Target and characters interact on floor.
( In Hierarchy, the floor object is the child object of Image Target, and in Scene, the floor is placed on Image Target. )


The problem here is that floor keeps shaking on top of AR Image Target.

Question 1. I want to create a virtual world at the marker location when I detect the AR marker in reality so that the floor is no longer shaken.
Is there a way to know the location of the AR marker when the actual AR marker is detected by the camera on the device?

Question 2. OnTrackingFound() call from the ITrackableEventHandler occurs. It's called too often, can i help lower the frequency?

please help, thank
In korea, keutana

 

Thank you for your advice. I posted same question on the forum, but there was no answer.
Can you help me get help?